Indian Patents. 218381:"A PROCESS FOR PREPARING A REMOTE FUNCTIONALISED DIAMINODICY ANOQUINODIMETHANES HAVING ENHANCED FLUORESCENCE IN THE SOLID STATE"

Title of Invention	"A PROCESS FOR PREPARING A REMOTE FUNCTIONALISED DIAMINODICY ANOQUINODIMETHANES HAVING ENHANCED FLUORESCENCE IN THE SOLID STATE"
Abstract	The present invention relates to remote funtionalised Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent, a process for preparing the remote functional ized DADQs, relates to novel polymeric substrate incorporated with the DADQs and a process for preparing such doped polymer.

Full Text	REMOTE FUNCTIONALISED DIAMINODICYANOQUINODIMETHANES HAVING ENHANCED FLUORESCENCE IN THE SOLID STATE FIELD OF INVENTION: The present invention relates to remote funtionalised Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent, having general formula A: (Formula Removed) Wherein: (Formula Removed) The present invention also relates to a process for preparing the remote functionalized DADQs as defined above. The present invention further relates to novel polymeric substrate incorporated with the DADQs and a process for preparing such doped polymer. BACKGROUND AND PRIOR ART REFERENCES The general class of Diaminodicyanoquinodimethanes, called DADQ's hereafter, were first synthesized by researchers at Du Pont, USA [L.R.Hertler, H.D.Hartzler, D.S.Acker, R.E.Benson, J. Am. Chem. Soc. 1962, 84, 3387]. Their work primarily describes synthesis aspects. The potential applications of some of the derivatives as dyes were covered by a US patent [D. S. Acker, D.C. Blomstrom, U S Patent 3,115,506]. The distinction between their work and the present invention lies in the actual molecules studied, detailed procedures for the synthesis of these molecules as well as the application potential. The systems studied now are all new molecules, though belonging to the general family of DADQ's. Their unique and distinguishing characteristic is the remote functional groups. The enhanced fluorescence is a novel property realized with the present systems, which were not with the ones reported by the Du Pont group. Several DADQ's have been developed earlier which have interesting nonlinear optical applications such as second harmonic generation. Only two compounds in this series have been reported to show enhanced fluorescence [D. Bloor, Y. Kagawa, M. Szablewski, M. Ravi, S. J. Clark, G. H. Cross, L. Palsson, A. Beeby, C. Farmer, G. Rumbles, J. Mater. Chem. 2001,11, 3053] (in viscous solvents, solid state and polymer films). However, these are not remote functionlized systems like the ones we describe and the previous work does not demonstrate quantitative aspects of fluorescence enhancement in the solid state or demonstrate reversible fluorescence switching of doped polymer films. OBJECTS OF INVENTION: The main object of the present invention is to provide remote functionalized Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent ie. in solution or for the doped polymer film, in presence of solvent vapours. Another object of the present invention is to provide a process for preparing the remote functionalised Diaminodicyanoquinodimethanes (DADQs). Yet another object of the present invention is to provide a polymeric substrate incorporated with remote functionlised DADQ's (doped polymer) for use in manufacturing vapor responsive switches and sensors. Still another object of the present invention is to provide a process for preparing polymeric substrate incorporated with remote functionalized DADQs (doped polymer). SUMMARY OF THE INVENTION The current interest in the photoluminescence and electroluminescence of molecular materials is a major impetus to explore novel chromophores which not only do not suffer fluorescence quenching in the aggregated state, but display enhanced light emission in the solid state and in polymer films. A new family of remote functionalised zwitterionic diaminodicyanoquinodimethanes (Figure 1) are synthesized and characterized by spectroscopic techniques. Crystal structures of two of the compounds are also determined (Figure 2). Electronic absorption and emission studies demonstrate a dramatic enhancement of light emission in the solid state of these compounds and their doped polymer films, as compared to the solution state (Table 1). A viable model to explain the interesting phenomenon of fluorescence enhancement has been worked out through semiempirical quantum chemical computations and the crystal structure information. Finally, reversible and reproducible switching of the enhanced fluorescence of a doped polymer film, triggered by chloroform vapors was demonstrated (Figure 3). This has considerable potential in the development of organic vapor-responsive switches and sensors. STATEMENT OF THE INVENTION The present invention relates to remote functionalised Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent solvent (ie. in solution or for the doped polymer film, in presence of solvent vapours), having general formula A: (Formula Removed) Wherein: (Formula Removed) The present invention further relates to a process for preparing of the remote functionalised Diaminodicyanoquinodimethanes (DADQs) having general formula A: (Formula Removed) wherein (Formula Removed) said process comprising the steps of: a. adding piperazine or its derivatives to a solution containing tetracyanoquinodimethane (TCNQ) or its derivatives; b. stirring the mixture of step (a) to form precipitate; c. filtering and drying the precipitate of step (b), and optionally d. dissolving the dried precipitate of step (c) in a solvent and adding p- toluenesulfonicacid to the solution to obtain the compound of general formula A. The present invention also relates to a polymeric substrate incorporated with remote functionalized DADQs (doped polymer), for use in manufacturing vapor responsive switches and sensors, said doped polymer comprising 98.7 to 99.2 wt % of a polymer and 1.3 to 0.8 wt % of the said remote functionalized DADQs and wherein the polymer used has substantially different solubility factor as compared to DADQs with respect to at least one solvent. The present invention further relates to a process for preparing of polymeric substrate incorporated with remote functionlised DADQ's (doped polymer), said process comprising the steps of: a. mixing 0.8 to 1.3 wt% of the said compound of general formula A as claimed in claim 1 with 99.2 to 98.7 wt% of the polymer, and b. casting the mixture of step (a) to the required shape using any of the conventional processes and drying the cast film to obtain the doped polymer DETAILED DESCRIPTION OF THE INVENTION: The present invention is related to novel DADQs having remote functional groups which differ from other DADQs in several aspects and which are essential to realize advantages over other DADQ's. The present invention presents detailed quantification of fluorescence enhancement in solid state and polymeric films doped with DADQs and demonstrates solvent vapour triggered fluorescence switching of said polymer films. In the present invention a semi-quantitative model based on quantum chemical computations for the mechanism of fluorescence enhancement is formulated. Since large numbers of systems are developed, the present work also establishes the generality of the fluorescence enhancement phenomenon in these materials and the molecular design principle involved. Accordingly, the present invention provides remote functionalised Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent, having general formula A : (Formula Removed) Wherein: (Formula Removed) In another embodiment of the present invention, wherein reduction in fluorescence of the remote functionalised DADQs compound is triggered by presence of an organic solvent ie. in solution. In yet another embodiment of the present invention, wherein reduction in fluorescence of the remote funtionalised DADQs is triggered by presence of the solvent is a reversible process. In still further embodiment of the present invention, wherein reduction in fluorescence of remote funtionalised DADQs is triggered by presence of the chloroform. In a further embodiment of the present invention, wherein ratio of the fluorescence intensity of the compound in solid state to the fluorescence intensity of the compound in acetonitrile solution is in the range of 20 to 250. In yet another embodiment of the present invention, wherein the remote functionalized DADQs having the substitutions (Formula Removed) has the following characteristics: M.P. = 278-280°C (dec); FTIR (KBr): v/cm-1 = 2172.0, 2135.4, 1595.3, UV-Vis (acetonitrile): λmax/nm = 269,420; 1H-NMR (CDC13): δ/ppm = 1.7 (s, 6H, 2.6-2.7 (m, 8H), 3.5-3.6 (m, 8H), 7.1 (s, 4H); 13C-NMR ([D6]DMSO) : δ/ppm = 34.5, 45.5, 50.9, 54.6, 114.1, 118.1, 123.2,131.8,149.8, 168.8; anal. (calc. for C20H26N6): % C = 68.31 (68.57), %H = 7.11 (7.43), %N = 24.61 (24.00), maximum absorption and emission intensity in solid state takes place at 422 nm and 492 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 420 nm and 543 nm respectively. In yet another embodiment of the present invention, wherein the remote functionalized DADQs having the substitution (Formula Removed) has the following characteristics: M.P. = 260-262°C (dec); FTIR (KBr) : v/cm-1 = 2941.7, 2170.1, 2133.5, 1595.3, UV-Vis (acetonitrile): λ max /nm = 267,407; 1H-NMR (CDC13): δ/ppm = 1.6 (s, 3H), 2.0 to 2.11 (t, 4H), 2.15-2.25 (t, 4H), 3.5-3.6 (t, 4H), 3.60-3.75 (t, 4H), 7.0 (s, 4H); 13C-NMR ([D6]DMSO) : δ/ppm = 24.1, 25.7, 33.1, 45.5, 50.1, 52.7, 54.6, 115.2, 118.1, 123.7, 130.5, 148.3,165.9; anal. (calc. for C19H23N5) : %C = 70.93 (71.03), %H - 7.22 (7.71), %N = 21.72 (21.80); maximum absorption and emission intensity in solid state takes place at 422 nm and 495 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 407 nm and 538 nm respectively. In yet another embodiment of the present invention, wherein the remote functionalized DADQs having the substitution (Formula Removed) has the following characteristics M.P.=245-246°C (dec); FTIR (KBr) : v/crn'1 = 3390.0, 2170.1, 2131.5, 1597.2; UV-Vis(acetonitrile) : λ max/nm = 273, 407; 'H-NMR ([D6]DMSO): δ/ppm=s1.9-2:l(m,3H)s 2.75-2.90 (m, 4H), 3.7-3.8 (m, 4H), 4.3-4.4 (m, 4H), 5.3(s, 1H), 6.8-6.9(d, 2H), 7.15-7.20 (d, 2H), hydroxy proton was not observed; I3C-NMR ([D6]DMSO): δ/ppm= 32.5, 33.1, 34.2, 46.1, 50.6, 51.8, 60.3, 67.6, 69.1, 115.1, 118.1, 123.8, 130.6, 148.3, 166.5; anal. (calc. for C18H21N5O): %C = 66.86 (66.87), %H = 6.49 (6.50), %N = 21.68 (21.67); maximum absorption and emission intensity in solid state takes place at 419 nm and 534 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 407 nm and 533 nm respectively. In yet another embodiment of the present invention, wherein the remote functionalized DADQs having the substitution (Formula Removed) has the following characteristics M.P.= 213-215°C (dec); FTIR (KBr) : v/cm-1 = 3308.0, 2170.0, 2131.0, 1597.0; UV-Vis (acetonitrile): λ max/nm = 270, 408; 1H-NMR([D6]DMSO): δ /ppm=1.8-2.1(m,3H), 2.7-2.9 (m, 4H), 3.6-3.9 (m, 4H), 4.2-4.5 (t, 4H), 5.3 (s, 1H), 6.8-6.9 (d, 2H), 7.2-7.35 (d, 2H), hydroxy proton was not observed; 13C-NMR ([D6]DMSO) δ/ppm=32.2, 33.0, 34.3, 46.0, 50.6, 51.7, 60.3, 68.0, 69.1, 115.1, 118.1, 123.8, 130.6, 148.3, 166.5; anal (calc. for C18H21N50): %C = 66.22 (66.87), %H = 6.85 (6.50), %N = 21.68 (21.67); maximum absorption and emission intensity in solid state takes place at 410 nm and 533 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 408 nm and 539 nm respectively. In yet another embodiment of the present invention, wherein the remote functionalised DADQs havin" the substitution (Formula Removed) has the following characteristics M.P.= 250-255°C(dec);FTIR (KBr):v/cm-1=3398.2, 3022.8, 2177.8, 2137.0, 1597.0, 1005.0, 887.0, 814.0; UV-Vis (acetoniajtrile): λ max/ nm-267, 422; 'H-NMR ([D6]DMSO):δ /ppm = 1.9-2.0 (m, 3H), 2.1-2.2 (m, 4H), 2.3(s,3H), 3.8-4.0(m,4H), 4.30-4.45 (t, 2H), 5.25-5.40 (m, 2H), 6.8-6.9 (m, 2H), 7.1-7.2(d,2H),7.3-7.4(m,2H), 7.5-7.6 (d, 2H), 8.85-9.15 (s, 2H), hydroxy proton was not observed; I3C-NMR([D6]DMSO) : δ /ppm = 21.0, 32.5, 33.3, 34.0, 43.1, 44.7, 49.7, 50.8, 60.1, 60.6, 67:5, 69.1, 114.7, 118.1, 123.7, 125.7, 128.4, 130.7, 138.2, 145.5, 148.5, 167.0, the extra peaks appear to result from clustering of the zwitterionic molecules, since their reproducibility was verified by repeated purification and the absence of impurities was further confirmed by the satisfactory elemental analysis; anal. (calc. for C25H29N5SO4 : %C = 60.62 (60.61), %H = 5.89 (5.86), %N = 14.24 (14.14); maximum absorption and emission intensity in solid state takes place at 418 nm and 518 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 422 nm and 540 nm respectively. In yet another embodiment of the present invention, wherein the remote functionalised DADQs having the substitution (Formula Removed) has the following characteristics M.P.= 239-244°C (dec); FTIR (KBr):v/cm-1=3362.2, 3015.0, 2177.8, 2137.3, 1597.2, 1005.0, 887.3, 814.0; UV-Vis (acetonitrile): λ max /nm = 265,408; 'H-NMR ([D6]DMSO): δ /ppm = 1.9-2.0 (m, 3H), 2.1-2.2 (m,4H), 2.3(s,3H), 3.6-3.9 (m, 4H), 4.25-4.45 (m, 2H), 5.25-5.40 (m, 2H), 6.8-6.9 (m, 2H), 7.1-7.2(d,2H),7.25-7.4 (m, 2H), 7.5-7.6 (d, 2H), 8.8-9.2 (s, 2H), hydroxy proton was not observed; 13C-NMR([D6]DMSO): δ /ppm= 21.0,32.6,33.7,34.1,43.0,47.1,50.7, 51.3, 60.0, 61.0, 67.6, 69.3, 114.5, 118.1, 123.6, 125.7, 128.4, 130.9, 138.4, 145.2, 148.8, 166.7, the extra peaks appear for the same reasons as described under 5; anal. (calc. for C25H29N5SO4):%C = 60.55 (60.61), %H =5.93 (5.86), %N - 14.21 (14.14); maximum absorption and emission intensity in solid state takes place at 403 nm and 531 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 408 nm and 536 nm respectively. The present invention also provides a process for preparing the remote funtionalised Diaminodicyanoquinodimethanes (DADQs) having general formula A: (Formula Removed) wherein: (Formula Removed) said process comprising the steps of: (a) adding piperazine or its derivatives to a solution containing tetracyanoquinodimethane (TCNQ) or its derivatives; (b) stirring the mixture of step (a) to form precipitate; (c) filtering and drying the precipitate of step (b), and optionally (d) dissolving the dried precipitate of step (c) in a solvent and adding p- toluenesulfonicacid to the solution to obtain the compound of general formula A. A still further embodiment of the present invention, the yield of the compound is in the range of 65% to 85%. Yet another embodiment of the present invention, the derivatives of piperazine used is N-methylpiperazine. Still another embodiment of the present invention, wherein the derivatives of TCNQ used are selected from 7-pyrrolidino-7,8,8-tricyanoquinodimethane (PTCNQ), 7-(3-hydroxypyrrolidino)-7,8,8-tricyanoquinodimethane (HPTCNQ) and 7-(3, R(+)-hydroxypyrrolidino)-7,8,8-tricyanoquinodimethane(RHPTCNQ). Yet another embodiment of the present invention, the solution containing tetracyanoquinodimethane (TCNQ) or its derivatives is obtained by dissolving tetracyanoquinodimethane (TCNQ) or its derivatives in acetonitrile. Still another embodiment of the present invention, the solution containing tetracyanoquinodimethane (TCNQ) or its derivatives is kept warm at the time of adding piperazine or its derivatives. Still further embodiment of the present invention, the reaction mixture is stirred at a temperature in the range of 30°C to 75°C. Further embodiment of the present invention, the reaction mixture is stirred for time period in the range of 0.5 hr to 2.0 hrs to obtain the precipitate. Further embodiment of the present invention, the precipitate is dissolved in acetonitrile and p-toluenesulfonicacid is added to this solution to obtain the compound of general formula A. Still further embodiment of the present invention, wherein the compound having general formula A with the substitution (Formula Removed) is prepared by mixing N-methylpiperazine to a warm acetonitrile solution containing TCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate thus formed to obtain said compound. Yet another embodiment of the present invention, wherein the compound having general formula A with the substitution (Formula Removed) is prepared by mixing N-methylpiperazine to a warm acetonitrile solution containing PTCNQ, stirring the reaction mixture till formation of precipitate and filtering the precipitate thus formed and drying the same to obtain said compound. Still another embodiment of the present invention, wherein the compound having general formula A with the substitution (Formula Removed) is prepared by mixing piperazine with a warm acetonitrile solution containing HPTCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate thus formed to obtain said compound. Yet another embodiment of the present invention, wherein the compound having general formula A with the substitution (Formula Removed) is prepared by mixing piperazine with a warm acetonitrile solution containing RHPTCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate formed to obtain said compound. Yet another embodiment of the present invention, wherein the compound having general formula A with the substitution (Formula Removed) is prepared by mixing piperazine with a warm acetonitrile solution containing HPTCNQ, stirring the reaction mixture till formation of precipitate, filtering and drying the precipitate thus formed, dissolving the dried precipitate in acetonitrile and mixing the solution thus obtained with acetonitrile solution of p-toluenesulfonic acid to obtain microcrystalline precipitate, filtering and drying the microcrystalline precipitate thus formed to obtain said compound. Yet another embodiment of the present invention, wherein the compound having general formula A with the substitution (Formula Removed) is prepared by mixing piperazine with a warm acetonitrile solution containing RHPTCNQ, stirring the reaction mixture till formation of precipitate, filtering and drying the precipitate thus formed, dissolving the dried precipitate in acetonitrile and mixing the solution thus obtained with acetonitrile solution of p-toluenesulfonic acid to obtain microcrystalline precipitate, filtering and drying the microcrystalline precipitate thus formed to obtain said compound. The present invention also provides a polymeric substrate incorporated with remote functionalized DADQs for use in manufacturing vapor responsive switches and sensors, said polymeric substrate comprising 98.7 to 99.2 wt % of a polymer and 1.3 to 0.8 wt % of the remote functionalized DADQs of the general formula A and wherein the polymer used has substantially different solubility factor as compared to DADQs with respect to at least one solvent. In still another embodiment of the present invention, the polymer used is selected from polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS). In one other embodiment of the present invention, wherein the doped polymer used has enhanced fluorescence in dry state and reduced fluorescence in presence of organic solvent vapours. In one more embodiment of the present invention, wherein reduction in fluorescence of the doped polymer is triggered by presence of chloroform. In yet another embodiment of the present invention, the reduction in fluorescence of the doped polymer in the presence of the solvent is reversible. In yet another embodiment of the present invention, the reduction in fluorescence of the doped polymer in the presence of the solvent is reproducible. In a further embodiment of the present invention, the doped polymer comprises 0.8 to 1.3 wt % of remote functionalized DADQ's of the general formula A and 99.2 to 98.7 wt % PVA polymer. In a further embodiment of the present invention, the doped polymer comprises 0.8 to 1.3 wt % of remote functionalized DADQ's of the general formula A and 99.2 to 98.7 wt % PSS polymer. In an embodiment of the present invention, the PVA polymer used has average molecular weight of 15,000. In another embodiment of the present invention, the PSS polymer used has average molecular weight of 70,000. In one more embodiment of the present invention, wherein the ratio of the fluorescence intensity of the said compounds in polymeric substrate to the fluorescence intensity of the compounds in acetonitrile solution is in the range of 20 to 220. In one another embodiment of the present invention, wherein the ratio of the fluorescence intensity of the said compounds in PSS film to the fluorescence intensity of the same compounds in acetonitrile solution is in the range of 20 to 140. The present invention further provides a process for preparing a polymeric substrate incorporated with remote functionalized DADQ's (doped polymers), said process comprising the steps of: a) mixing 0.8 to 1.3 wt% of the said compound of general formula A in 99.2 to 98.7 wt% of the polymer, and b) casting the mixture of step (a) to the required shape using any of the conventional processes and drying the cast film to obtain the doped polymer. Still another embodiment of the present invention, the casting of reaction mixture is carried out by spinning process. Yet another embodiment of the present invention, wherein drying is carried out for time period in the range of 1 hrs to 2 hrs. Yet another embodiment of the present invention, wherein polymer is selected from polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS). Remote functionalised DADQ's are new molecules having remote groups attached to the DADQ, which facilitate novel molecular assemblies without perturbing the chromophore properties and impart a number of interesting characteristics to DADQs. The remote functionalized DADQs can be used in several applications such as (i) steering centrosymmetric crystal lattice into SHG active noncentric ones, (ii) instance o f charge transfer phenomenon exclusively in the solid state and (iii) fabrication of desired molecular environment of interest in modeling studies. A very important advantage derived from the presence of remote functionality on the DADQ's is the solubility of the compounds in water in addition to regular organic solvents. DADQ's which are not remote functionalized are generally either insoluble in water or undergo hydrolytic decomposition in water. Since the synthesized remote functionalized DADQ's are soluble in water and form stable aqueous solution, they can be incorporated in water soluble polymers. This allows the fabrication of doped polymer films which can be used for organic vapour sensing. Finally the remote functionality on the DADQs allows intermolecular interactions which appear to be important for the molecular aggregation and fluorescence enhancement. The spectroscopic data on the new remote functionalized DADQ's allow to quantify the fluorescence enhancement in solid state and doped polymer films. None of the earlier studies on DADQs have demonstrated the type of reversibility and stability of fluorescence switching of the fluorescence on exposure to solvent or solvent vapors that the Applicants have demonstrated with doped polymer films containing the remote functionalized DADQ's. None o f the e arlier D ADQs are known t o b e w ater-soluble a nd forming s table a queous solutions and the Applicants have been able to prepare remote functionalized DADQs that are water-soluble and stable in aqueous solution for the first time. Finally, the detailed modeling the Applicants have carried out for the mechanism of fluorescence enhancement is not available in the case of any of the systems reported earlier. The mechanism for the fluorescence enhancement in the remote functionalised DADQ's has been worked out with the aid of semiempirical quantum chemical computations. The concept of 'molecule-in-a-crystal' developed earlier by the Applicants was utilized. Semiempirical AMI computations incorporating the solvation modeling routine, COSMO showed that the fluorescence observed arise from the vertical excited state. The computations showed that the geometry relaxed excited state would not show fluorescence in the visible range. Geometry relaxation is possible in solution, but unlikely in the solid state and in doped polymer films. Therefore, it is concluded that the fluorescence enhancement observed in the latter cases arises due to effective inhibition of the geometry relaxation. This mechanism is quite different from that proposed in the earlier systems. When an optical property such as fluorescence (light emission) is affected reversibly by the presence or absence of a vapour; it can be an effective way to sense the vapour. Alternately the vapour can be used to switch on or off the optical signal and in this sense, the material can be used as a transducer where the vapour is the stimulus and optical signal is the response. Both these applications require that the process happens reversibly and reproducibly, Finally, polymer films have an important advantage that they can be produced cheaply and can be fabricated for large area coverage. This allows the sensing or switching element to be prepared economically. Doped polymer films allow fine control of dopant concentration and therefore, the optical response can be fine tuned based on the application needs. BRIEF DESCRIPTION OF FIGURES: 1. Fig 1 shows the general formula of remote functionalized DADQ's. 2. Fig.2 s hows t he molecular s tructure (from crystal structure analysis) o f so me o f t he remote functionalized DADQs as synthesized in the present invention. 3. Fig.3 depicts the variation of emission maximum of PVA film incorporated with DADQ in presence and absence of chloroform vapor. Figure 2 shows the molecular structure of the remote functionalized DADQ in the crystalline state for the DADQs with the substitutions as shown in options 1 and 2 for A. Crystal structure analysis is possible only when large enough single crystals can be grown. The general structure is indicated for these and all other compounds in Fig. 1. Figure 3 describes the phenomenon of the variation of the fluorescence emission maximum of doped polymers in presence/absence of chloroform vapor. In the dry state, the fluorescence is high (the filled square marks in the graph). On exposure to chloroform vapors, the fluorescence decreases (the filled circle marks in the graph). Both fluorescence are visible to naked eye under ambient lighting which has a UV (ultra-violet) component. However, the fluorescence in the dry state is, of course, more visible. The fluorescence is best observed using 350-360 nm light from a UV lamp for excitation. Table 1 provides the wavelength (denoted by Greek letter lambda, expressed in nanometers, nm) of light at which each of the compound absorbs most, when in solution, in the solid state and when doped in polymer films (the superscript for lambda, abs, indicates this). The table also provides the wavelength where the fluorescence (same as emission) in each of these states is maximum for each of the compound (the superscript for lambda, em, indicates this). R is the ratio of the fluorescence intensity in the solid state or polymer film, compared to the fluorescence intensity of the same compound in acetonitrile solution. This number indicates the enhancement of fluorescence in the solid state and polymer film, compared to the solution state. Table 1. Visible absorption (λ maxabs) and emission (λ maxem) peaks of 1 - 6 in acetonitrile solution, solid state and in PV A and PSS films and the fluorescence enhancement, R of the solid and polymer films over that in acetonitrile solution. (Table Removed) WE CLAIM: 1. Remote functionalised Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent (ie. in solution or for the doped polymer film, in presence of solvent vapours), having general formula A: (Formula Removed) Wherein: (Formula Removed) 2. Remote functionalized DADQs as claimed in claim 1, wherein reduction in fluorescence of the compound is triggered by presence of an organic solvent. 3. Remote functionalized DADQs as claimed in claim 1, wherein the reduction in fluorescence of the compound is triggered by presence of the solvent is a reversible process. 4. Remote functional ized DADQs as claimed in claim 1, wherein the organic solvent is chloroform. 5. Remote functionalized DADQs as claimed in claim 1, wherein the ratio of the fluorescence intensity of the compound in solid state to the fluorescence intensity of the compound in presence of Acetonitrile solution is in the range of 20 to 350 220. 6. Remote functionalized DADQs as claimed in claim 1, wherein if the substitution is the compound has the following characteristics: M.P. = 278-280°C (dec); FTIR (Formula Removed) (KBr): v/cm-1 = 2172.0, 2135.4, 1595.3, UV-Vis (acetonitrile): λma/nm = 269,420; 'H-NMR (CDC13): δ/ppm = 1.7 (s, 6H, 2.6-2.7 (m, 8H), 3.5-3.6 (m, 8H), 7.1 (s, 4H); 13C-NMR ([D6]DMSO) : 8 /ppm = 34.5, 45.5, 50.9, 54.6, 114.1, 118.1, 123.2,131.8,149.8, 168.8; anal. (calc. for C2oH26N6): % C = 68.31 (68-57), %H -7.11 (7.43), %N = 24.61 (24,00), maximum absorption and emission intensity in solid state takes place at 422 nm and 492 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 420 nm and 543 nm respectively. 7. Remote functional ised DADQs as claimed in claim 1, wherein if the substitution is the compound has the following characteristics: M.P. = 260-262°C (dec); FTIR (Formula Removed) (KBr) : v/cm'1 = 2941.7, 2170.1, 2133.5, 1595.3, UV-Vis (acetonitrile): λmax /nm = 267,407;'H-NMR (CDC13): δ/ppm = 1.6 (s, 3H), 2.0 to 2.11 (t, 4H), 2.15-2.25 (t, 4H), 3.5-3.6 (t, 4H), 3.60-3.75 (t, 4H), 7.0 (s, 4H); 13C-NMR ([D6]DMSO) : 8 /ppm = 24.1, 25.7, 33.1, 45.5, 50.1, 52.7, 54.6, 115.2, 118.1, 123.7, 130.5, 148.3,165.9; anal. (calc. for C19H23N5): %C = 70.93 (71.03), %H - 7.22:(7.71), %N = 21.72 (21.80); maximum absorption and emission intensity in solid state takes place at 422 nm and 495 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 407 nm and 538 nm respectively. 8. Remote functionalised DADQs as claimed in claim 1, wherein if the substitution is the compound has the following characteristics M.P.=245-246°C (dec); FTIR (Formula Removed) (KBr) : v/cm'1 = 3390.0, 2170.1, 2131.5, 1597.2; UV-Vis(acetonitrile) : λma/nm = 273, 407; 1H-NMR([D6]DMSO): δ /ppm=1.9-2:l(m,3H), 2.75-2.90 (m, 4H), 3.7-3.8 (m, 4H), 4.3-4.4 (m, 4H), 5.3(s, 1H), 6.8-6.9(d, 2H), 7.15-7.20 (d, 2H), hydroxy proton was not observed; 13C-NMR ([D6]DMSO): 8/pprn^= 32.5, 33.1, 34.2, 46.1, 50.6, 51.8, 60.3, 67.6, 69.1, 115.1, 118.1, 123.8, 130.6, 148.3, 166.5; anal. (calc. for C18H21N5O): %C = 66.86 (66.87), %H = 6.49 (6.50), %N = 21.68 (21.67); maximum absorption and emission intensity in solid state takes place at 4 19 nm and 534 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 407 nm and 533 nm respectively. 9. Remote functionalised DADQs as claimed in claim 1, wherein if the substitution is the compound has the following characteristics M.P.= 213-215°C (dec); FTIR (Formula Removed) (KBr) : v/cm'1 = 3308.0, 2170.0, 2131.0, 1597.0; UV-Vis (acetonitrile): λma/ nm = 270, 408; 'H-NMR([D6]DMSO): δ /ppm=1.8-2.1(m,3H), 2.7-2.9 (m, 4H), 3.6-3.9 (m, 4H), 4 .2-4.5 (t, 4H), 5 .3 (s, 1 H), 6 .8-6.9 (d, 2H), 7 .2-7.35 (d, 2H), hydroxy proton was not observed; I3C-NMR (D6DMSO) 5/ppm=32.2, 33.0, 34.3, 46.0, 50.6, 51.7, 60.3, 68.0, 69.1, 115.1, 118.1, 123.8, 130.6, 148.3, 166.5; anal (calc. for C18H21N5O): %C - 66.22 (66.87), %H = 6.85 (6.50), %N = 21.68 (21.67); maximum absorption and emission intensity in solid state takes place at 410 nm and 553 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 408 nm and 539 nm respectively. 10. Remote functional ised DADQs as claimed in claim 1 , wherein if the substitution is (Formula Removed) the compound has the following characteristics M.P.= 250-255°C(dec);FTIR (KBr): v/cm'=3398.2, 3022.8, 2177.8, 2137.0, 1597.0, 1005.0, 887.0, 814.0; UV-Vis (acetoajtrile): λmax/nm-267, 422; 'H-NMR ([D6]DMSO): 8 /ppm = 1.9-2.0 (m, 3H), 2.1-2.2 (m, 4H), 2.3(s,3H), 3.8-4.0(m,4H), 4.30-4.45 (t, 2H), 5.25-5.40 (m, 2H), 6.8-6.9 (m, 2H), 7.1-7.2(d,2H),7.3-7.4(m,2H), 7.5-7.6 (d, 2H), 8.85-9.15 (s, 2H), hydroxy proton was not observed; I3C-NMR([D6]DMSO) : δ /ppm = 21.0, 32.5, 33.3, 34.0, 43.1, 44.7, 49.7, 50.8, 60.1, 60.6, 67:5, 69.1, 1 14.7, 1 18.1, 123.7, 125.7, 128.4, 130.7, 138.2, 145.5, 148.5, 167.0, the extra peaks appear to result from clustering of the zwitterionic molecules, since their reproducibility was verified by repeated purification and the absence of impurities was further confirmed by the satisfactory elemental analysis; anal. (calc. for C25H29NSO4 : %C = 60.62 (60.61), %H = 5.89 (5.86), %N = 14.24 (14.14); maximum absorption and emission intensity in solid state takes place at 418 nm and 518 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 422 nm and 540 nm respectively. Remote functional ised DADQs as claimed in claim 1, wherein if the substitution is (Formula Removed) the compound has the following characteristics M.P.= 239-244°C (dec); FTIR (KBr):v/cm'=3362.2, 3015.0, 2177.8, 2137.3, 1597.2, 1005.0, 887.3, 814.0; UV-Vis (acetonitrile): λ max /nm = 265,408;'H-NMR ([D6]DMSO): δ/ppm =1.9-2.0 (m, 3H), 2.1-2.2 (m,4H), 2.3(s,3H), 3.6-3.9 (m, 4H), 4.25-4.45 (m, 2H), 5.25-5.40 (m, 2H), 6.8-6.9 (m, 2H), 7.1-7.2(d,2H),7.25-7.4 (m, 2H), 7.5-7.6 (d, 2H), 8.8-9.2 (s, 2H), hydroxy proton was not observed; 13C-NMR ([D6]DMSO) :δ/ppm = 21.0, 32.6, 33.7, 34.1, 43.0, 47.1, 50.7, 51.3, 60.0, 61.0, 67.6, 69.3, 114.5, 118.1, 123.6, 125.7, 128.4, 130.9, 138.4, 145.2, 148.8, 166.7, the extra peaks appear for the same reasons as described under 11; anal. (calc. for C25H29N5SO4):%C = 60.55 (60.61), %H = 5.93 (5.86), %N = 14.21 (14.14); maximum absorption and emission intensity in solid state takes place at 403 nm and 531 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 408 nm and 536 nm respectively. 12. A process for preparing the remote functionalised Diaminodicyanoquinodimethanes (DADQs) having general formula A: (Formula Removed) wherein: (Formula Removed) said process comprising the steps of: a. adding piperazine or its derivatives to a solution containing tetracyanoquinodimethane (TCNQ) or its derivatives; b. stirring the mixture of step (a) to form precipitate; c. filtering and drying the precipitate of step (b), and optionally d. dissolving the dried precipitate of step (c) in a solvent and adding p- toluenesulfonicacid to the solution to obtain the compound of general formula A. 13. A process as claimed in claim 12, wherein the yield of the compound is in the range of 65% to 85%. 14. A process as claimed in claim 12 wherein in step (a), the derivatives of piperazine used is N-methylpiperazine. 15. A process as claimed in claim 12 wherein in step (a), the derivatives of TCNQ used are selected from 7-pyrrolidino-7,8,8-tricyanoquinodimethane (PTCNQ), 7-(3- hydroxypyrrolidino)-7,8,8-tricyanoquinodimethane (HPTCNQ) and 7-(3, R(+)- hydroxypyrrolidino)-7,8,8-tricyanoquinodimethane(RHPTCNQ). 16. A process as claimed in claim 12 wherein in step (a), the solution containing tetracyanoquinodimethane (TCNQ) or its derivatives is obtained by dissolving tetracyanoquinodimethane (TCNQ) or its derivatives in acetonitrile. 17. A process as claimed in claim 12 wherein in step (a), the solution containing tetracyanoquinodimethane (TCNQ) or its derivatives is kept warm at the time of adding piperazine or its derivatives. 18. A process as claimed in claim 12 wherein in step (b), the reaction mixture is stirred at a temperature in the range of 30°C to 75°C. 19. A process as claimed in claim 12 wherein in step (b), the reaction mixture is stirred for time period in the range of 0.5 hr to 2.0 hrs to obtain the precipitate. 20. A process as claimed in claim 12 wherein in step (d), the precipitate is dissolved in acetonitrile and p-toluenesulfonicacid is added to this solution to obtain the compound of general formula A. 21. A process as claimed in claim 12, wherein the compound having general formula A with the substitution (Formula Removed) is prepared by mixing N-methylpiperazine to a warm acetonitrile solution containing TCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate thus formed to obtain said compound. 22. A process as claimed in claim 12, wherein the compound having general formula A with the substitution (Formula Removed) is prepared by mixing N-methylpiperazine to a warm acetonitrile solution containing PTCNQ, stirring the reaction mixture till formation of precipitate and filtering the precipitate thus formed and drying the same to obtain said compound. 23. A process as claimed in claim 12, wherein the compound of general formula A with the substitution: (Formula Removed) is prepared by mixing piperazine with a warm acetonitrile solution containing HPTCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate thus formed to obtain said compound. 24. A process as claimed in claim 12, wherein the compound of general formula A with the substitution: (Formula Removed) is prepared by mixing piperazine with a warm acetonitrile solution containing RHPTCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate formed to obtain said compound. 25. A process as claimed in claim 12, wherein the compound of general formula A with the substitution: (Formula Removed) is prepared by mixing piperazine with a warm acetonitrile solution containing HPTCNQ, stirring the reaction mixture till formation of precipitate, filtering and drying the precipitate thus formed, dissolving the dried precipitate in acetonitrile and mixing the solution thus obtained with acetonitrile solution of p-toluenesulfonic acid to obtain microcrystalline precipitate, filtering and drying the microcrystalline precipitate thus formed to obtain said compound. 26. A process as claimed in claim 12, wherein the compound of general formula A with the substitution: (Formula Removed) is prepared by mixing piperazine with a warm acetonitrile solution containing RHPTCNQ, stirring the reaction mixture till formation of precipitate, filtering and drying the precipitate thus formed, dissolving the dried precipitate in acetonitrile and mixing the solution thus obtained with acetonitrile solution of p-toluenesulfonic acid to obtain microcrystalline precipitate, filtering and drying the microcrystalline precipitate thus formed to obtain said compound. 27. A polymeric substrate incorporated with remote functionalized DADQs as claimed in claim 1 (doped polymer), for use in manufacturing vapor responsive switches and sensors, said doped polymer comprising 98.7 to 99.2 wt % of a polymer and 1.3 to 0.8 wt % of the remote functionalized DADQs of claim 1 and wherein the polymer used has substantially different solubility factor as compared to DADQs with respect to at least one solvent. 28. A doped polymer as claimed in claim 27, wherein the polymer used i s selected from polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS). 29. A doped polymer as claimed in claim 27, wherein the doped polymer has enhanced fluorescence in dry state and reduced fluorescence in presence of organic solvent vapours. 30. A doped polymer as claimed in claim 29, wherein reduction in fluorescence of the doped polymer is triggered by presence of chloroform. 31. A doped polymer as claimed in claim 29, wherein the reduction in fluorescence of the doped polymer, in the presence, of the solvent is reversible. 32. A doped polymer as claimed in claim 29, wherein the reduction in fluorescence of the doped polymer, in the presence of the solvent is reproducible. 33. A doped polymer as claimed in claim 28, wherein the doped polymer comprises 99.2 to 98.7 wt % of PVA polymer and 0.8 to 1.3 wt % of DADQs of the general formula A. 34. A doped polymer a s claimed in claim 28, wherein the doped olymer c omprises 99.2 to 98.7 wt % of PSS polymer and 0.8 to 1.3 wt % of DADQ's of the general formula A. 35. A doped polymer as claimed in claim 28, wherein PVA polymer used has average molecular weight 15,000. 36. A doped polymer as claimed in claim 28, wherein PSS polymer has average molecular weight 70,000. 37. A doped polymer as claimed in claim 28, wherein the ratio of the fluorescence intensity of the said compounds in polymeric substrates the fluorescence intensity of the said compounds in acetonitrile solution is in the range of 20 to 220. 38. A doped polymer as claimed in claim 28, wherein the ratio of the fluorescence intensity of the said compounds in PSS film or PVA film to the fluorescence intensity of the said compounds in acetonitrile solution is in the range of 20 to 140. 39. A process for preparing of polymeric substrate incorporated with remote functionlised DADQ's (doped polymer) as claimed in claim 29, said process comprising the steps of: a. mixing 0.8 to 1.3 wt% of the said compound of general formula A as claimed in claim 1 with 99.2 to 98.7 wt% of the polymer, and b. casting the mixture of step (a) to the required shape using any of the conventional processes and drying the cast film to obtain the doped polymer. 40. A process as claimed in claim 41 wherein in step (a), polymer is selected from polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS). 41. A process as claimed in claim 41 wherein in step (b), casting of mixture is carried out by spinning process. 42. A process as claimed in claim 41 wherein in step (b), drying is carried out for time period in the range of 1 hrs to 2 hrs. 43. Remote functionalised Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent, substantially as herein described and illustrated therein. 44. A process for preparing the remote functionalised Diaminodicyanoquinodimethanes (DADQs) having general formula A, substantially as herein described and illustrated therein. 45. A polymeric substrate incorporated with remote functionalized DADQs, substantially as herein described and illustrated therein. 46. A process for preparing of polymeric substrate incorporated with remote functionlised DADQ's (doped polymer), substantially as herein described and illustrated therein.

Full Text

REMOTE FUNCTIONALISED DIAMINODICYANOQUINODIMETHANES HAVING ENHANCED FLUORESCENCE IN THE SOLID STATE
FIELD OF INVENTION:
The present invention relates to remote funtionalised Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent, having general formula A:

(Formula Removed)
Wherein:
(Formula Removed)
The present invention also relates to a process for preparing the remote functionalized DADQs as defined above. The present invention further relates to novel polymeric substrate incorporated with the DADQs and a process for preparing such doped polymer.
BACKGROUND AND PRIOR ART REFERENCES
The general class of Diaminodicyanoquinodimethanes, called DADQ's hereafter, were first synthesized by researchers at Du Pont, USA [L.R.Hertler, H.D.Hartzler, D.S.Acker, R.E.Benson, J. Am. Chem. Soc. 1962, 84, 3387]. Their work primarily describes synthesis

aspects. The potential applications of some of the derivatives as dyes were covered by a US patent [D. S. Acker, D.C. Blomstrom, U S Patent 3,115,506]. The distinction between their work and the present invention lies in the actual molecules studied, detailed procedures for the synthesis of these molecules as well as the application potential. The systems studied now are all new molecules, though belonging to the general family of DADQ's. Their unique and distinguishing characteristic is the remote functional groups. The enhanced fluorescence is a novel property realized with the present systems, which were not with the ones reported by the Du Pont group. Several DADQ's have been developed earlier which have interesting nonlinear optical applications such as second harmonic generation. Only two compounds in this series have been reported to show enhanced fluorescence [D. Bloor, Y. Kagawa, M. Szablewski, M. Ravi, S. J. Clark, G. H. Cross, L. Palsson, A. Beeby, C. Farmer, G. Rumbles, J. Mater. Chem. 2001,11, 3053] (in viscous solvents, solid state and polymer films). However, these are not remote functionlized systems like the ones we describe and the previous work does not demonstrate quantitative aspects of fluorescence enhancement in the solid state or demonstrate reversible fluorescence switching of doped polymer films.
OBJECTS OF INVENTION:
The main object of the present invention is to provide remote functionalized
Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid
state and reduced fluorescence in presence of organic solvent ie. in solution or for the
doped polymer film, in presence of solvent vapours.
Another object of the present invention is to provide a process for preparing the remote
functionalised Diaminodicyanoquinodimethanes (DADQs).
Yet another object of the present invention is to provide a polymeric substrate incorporated
with remote functionlised DADQ's (doped polymer) for use in manufacturing vapor
responsive switches and sensors.
Still another object of the present invention is to provide a process for preparing polymeric
substrate incorporated with remote functionalized DADQs (doped polymer).

SUMMARY OF THE INVENTION
The current interest in the photoluminescence and electroluminescence of molecular materials is a major impetus to explore novel chromophores which not only do not suffer fluorescence quenching in the aggregated state, but display enhanced light emission in the solid state and in polymer films. A new family of remote functionalised zwitterionic diaminodicyanoquinodimethanes (Figure 1) are synthesized and characterized by spectroscopic techniques. Crystal structures of two of the compounds are also determined (Figure 2). Electronic absorption and emission studies demonstrate a dramatic enhancement of light emission in the solid state of these compounds and their doped polymer films, as compared to the solution state (Table 1). A viable model to explain the interesting phenomenon of fluorescence enhancement has been worked out through semiempirical quantum chemical computations and the crystal structure information. Finally, reversible and reproducible switching of the enhanced fluorescence of a doped polymer film, triggered by chloroform vapors was demonstrated (Figure 3). This has considerable potential in the development of organic vapor-responsive switches and sensors.
STATEMENT OF THE INVENTION
The present invention relates to remote functionalised Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent solvent (ie. in solution or for the doped polymer film, in presence of solvent vapours), having general formula A:
(Formula Removed)

Wherein:
(Formula Removed)
The present invention further relates to a process for preparing of the remote functionalised Diaminodicyanoquinodimethanes (DADQs) having general formula A:

(Formula Removed)
wherein

(Formula Removed)

said process comprising the steps of:
a. adding piperazine or its derivatives to a solution containing
tetracyanoquinodimethane (TCNQ) or its derivatives;
b. stirring the mixture of step (a) to form precipitate;
c. filtering and drying the precipitate of step (b), and optionally
d. dissolving the dried precipitate of step (c) in a solvent and adding p-
toluenesulfonicacid to the solution to obtain the compound of general formula A.
The present invention also relates to a polymeric substrate incorporated with remote functionalized DADQs (doped polymer), for use in manufacturing vapor responsive switches and sensors, said doped polymer comprising 98.7 to 99.2 wt % of a polymer and 1.3 to 0.8 wt % of the said remote functionalized DADQs and wherein the polymer used has substantially different solubility factor as compared to DADQs with respect to at least one solvent.
The present invention further relates to a process for preparing of polymeric substrate incorporated with remote functionlised DADQ's (doped polymer), said process comprising the steps of:
a. mixing 0.8 to 1.3 wt% of the said compound of general formula A as claimed in
claim 1 with 99.2 to 98.7 wt% of the polymer, and
b. casting the mixture of step (a) to the required shape using any of the conventional
processes and drying the cast film to obtain the doped polymer
DETAILED DESCRIPTION OF THE INVENTION:
The present invention is related to novel DADQs having remote functional groups which differ from other DADQs in several aspects and which are essential to realize advantages over other DADQ's. The present invention presents detailed quantification of fluorescence enhancement in solid state and polymeric films doped with DADQs and demonstrates solvent vapour triggered fluorescence switching of said polymer films.

In the present invention a semi-quantitative model based on quantum chemical computations for the mechanism of fluorescence enhancement is formulated. Since large numbers of systems are developed, the present work also establishes the generality of the fluorescence enhancement phenomenon in these materials and the molecular design principle involved.
Accordingly, the present invention provides remote functionalised Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent, having general formula A :
(Formula Removed)
Wherein:
(Formula Removed)
In another embodiment of the present invention, wherein reduction in fluorescence of the remote functionalised DADQs compound is triggered by presence of an organic solvent ie. in solution.

In yet another embodiment of the present invention, wherein reduction in fluorescence of the remote funtionalised DADQs is triggered by presence of the solvent is a reversible process.
In still further embodiment of the present invention, wherein reduction in fluorescence of remote funtionalised DADQs is triggered by presence of the chloroform.
In a further embodiment of the present invention, wherein ratio of the fluorescence intensity of the compound in solid state to the fluorescence intensity of the compound in acetonitrile solution is in the range of 20 to 250.
In yet another embodiment of the present invention, wherein the remote functionalized DADQs having the substitutions
(Formula Removed)
has the following characteristics: M.P. = 278-280°C (dec); FTIR (KBr): v/cm-1 = 2172.0, 2135.4, 1595.3, UV-Vis (acetonitrile): λmax/nm = 269,420; 1H-NMR (CDC13): δ/ppm = 1.7 (s, 6H, 2.6-2.7 (m, 8H), 3.5-3.6 (m, 8H), 7.1 (s, 4H); 13C-NMR ([D6]DMSO) : δ/ppm = 34.5, 45.5, 50.9, 54.6, 114.1, 118.1, 123.2,131.8,149.8, 168.8; anal. (calc. for C20H26N6): % C = 68.31 (68.57), %H = 7.11 (7.43), %N = 24.61 (24.00), maximum absorption and emission intensity in solid state takes place at 422 nm and 492 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 420 nm and 543 nm respectively.
In yet another embodiment of the present invention, wherein the remote functionalized DADQs having the substitution
(Formula Removed)
has the following characteristics: M.P. = 260-262°C (dec); FTIR (KBr) : v/cm-1 = 2941.7, 2170.1, 2133.5, 1595.3, UV-Vis (acetonitrile): λ max /nm = 267,407; 1H-NMR (CDC13): δ/ppm = 1.6 (s, 3H), 2.0 to 2.11 (t, 4H), 2.15-2.25 (t, 4H), 3.5-3.6 (t, 4H), 3.60-3.75 (t, 4H), 7.0 (s, 4H); 13C-NMR ([D6]DMSO) : δ/ppm = 24.1, 25.7, 33.1, 45.5, 50.1, 52.7, 54.6, 115.2, 118.1, 123.7, 130.5, 148.3,165.9; anal. (calc. for C19H23N5) : %C = 70.93 (71.03), %H - 7.22 (7.71), %N = 21.72 (21.80); maximum absorption and emission intensity in solid state takes place at 422 nm and 495 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 407 nm and 538 nm respectively.
In yet another embodiment of the present invention, wherein the remote functionalized DADQs having the substitution
(Formula Removed)
has the following characteristics M.P.=245-246°C (dec); FTIR (KBr) : v/crn'1 = 3390.0, 2170.1, 2131.5, 1597.2; UV-Vis(acetonitrile) : λ max/nm = 273, 407; 'H-NMR ([D6]DMSO): δ/ppm=s1.9-2:l(m,3H)s 2.75-2.90 (m, 4H), 3.7-3.8 (m, 4H), 4.3-4.4 (m, 4H), 5.3(s, 1H), 6.8-6.9(d, 2H), 7.15-7.20 (d, 2H), hydroxy proton was not observed; I3C-NMR ([D6]DMSO): δ/ppm= 32.5, 33.1, 34.2, 46.1, 50.6, 51.8, 60.3, 67.6, 69.1, 115.1, 118.1, 123.8, 130.6, 148.3, 166.5; anal. (calc. for C18H21N5O): %C = 66.86 (66.87), %H = 6.49 (6.50), %N = 21.68 (21.67); maximum absorption and emission intensity in solid state takes place at 419 nm and 534 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 407 nm and 533 nm respectively.
In yet another embodiment of the present invention, wherein the remote functionalized DADQs having the substitution
(Formula Removed)
has the following characteristics M.P.= 213-215°C (dec); FTIR (KBr) : v/cm-1 = 3308.0, 2170.0, 2131.0, 1597.0; UV-Vis (acetonitrile): λ max/nm = 270, 408; 1H-NMR([D6]DMSO): δ /ppm=1.8-2.1(m,3H), 2.7-2.9 (m, 4H), 3.6-3.9 (m, 4H), 4.2-4.5 (t, 4H), 5.3 (s, 1H), 6.8-6.9 (d, 2H), 7.2-7.35 (d, 2H), hydroxy proton was not observed; 13C-NMR ([D6]DMSO) δ/ppm=32.2, 33.0, 34.3, 46.0, 50.6, 51.7, 60.3, 68.0, 69.1, 115.1, 118.1, 123.8, 130.6, 148.3, 166.5; anal (calc. for C18H21N50): %C = 66.22 (66.87), %H = 6.85 (6.50), %N = 21.68 (21.67); maximum absorption and emission intensity in solid state takes place at 410 nm and 533 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 408 nm and 539 nm respectively.
In yet another embodiment of the present invention, wherein the remote functionalised DADQs havin" the substitution
(Formula Removed)
has the following characteristics M.P.= 250-255°C(dec);FTIR (KBr):v/cm-1=3398.2, 3022.8, 2177.8, 2137.0, 1597.0, 1005.0, 887.0, 814.0; UV-Vis (acetoniajtrile): λ max/ nm-267, 422; 'H-NMR ([D6]DMSO):δ /ppm = 1.9-2.0 (m, 3H), 2.1-2.2 (m, 4H), 2.3(s,3H), 3.8-4.0(m,4H), 4.30-4.45 (t, 2H), 5.25-5.40 (m, 2H), 6.8-6.9 (m, 2H), 7.1-7.2(d,2H),7.3-7.4(m,2H), 7.5-7.6 (d, 2H), 8.85-9.15 (s, 2H), hydroxy proton was not observed; I3C-NMR([D6]DMSO) : δ /ppm = 21.0, 32.5, 33.3, 34.0, 43.1, 44.7, 49.7, 50.8, 60.1, 60.6, 67:5, 69.1, 114.7, 118.1, 123.7, 125.7, 128.4, 130.7, 138.2, 145.5, 148.5, 167.0, the extra peaks appear to result from clustering of the zwitterionic molecules, since their reproducibility was verified by repeated purification and the absence of impurities was further confirmed by the satisfactory elemental analysis; anal. (calc. for C25H29N5SO4 : %C = 60.62 (60.61), %H = 5.89 (5.86), %N = 14.24 (14.14); maximum absorption and emission intensity in solid state takes place at 418 nm and 518 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 422 nm and 540 nm respectively.
In yet another embodiment of the present invention, wherein the remote functionalised DADQs having the substitution

(Formula Removed)
has the following characteristics M.P.= 239-244°C (dec); FTIR (KBr):v/cm-1=3362.2,
3015.0, 2177.8, 2137.3, 1597.2, 1005.0, 887.3, 814.0; UV-Vis (acetonitrile): λ max /nm = 265,408; 'H-NMR ([D6]DMSO): δ /ppm = 1.9-2.0 (m, 3H), 2.1-2.2 (m,4H), 2.3(s,3H), 3.6-3.9 (m, 4H), 4.25-4.45 (m, 2H), 5.25-5.40 (m, 2H), 6.8-6.9 (m, 2H), 7.1-7.2(d,2H),7.25-7.4 (m, 2H), 7.5-7.6 (d, 2H), 8.8-9.2 (s, 2H), hydroxy proton was not observed; 13C-NMR([D6]DMSO): δ /ppm= 21.0,32.6,33.7,34.1,43.0,47.1,50.7, 51.3, 60.0, 61.0, 67.6, 69.3, 114.5, 118.1, 123.6, 125.7, 128.4, 130.9, 138.4, 145.2, 148.8, 166.7, the extra peaks appear for the same reasons as described under 5; anal. (calc. for C25H29N5SO4):%C = 60.55 (60.61), %H =5.93 (5.86), %N - 14.21 (14.14); maximum absorption and emission intensity in solid state takes place at 403 nm and 531 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 408 nm and 536 nm respectively.

The present invention also provides a process for preparing the remote funtionalised Diaminodicyanoquinodimethanes (DADQs) having general formula A:
(Formula Removed)
wherein:
(Formula Removed)
said process comprising the steps of:
(a) adding piperazine or its derivatives to a solution containing
tetracyanoquinodimethane (TCNQ) or its derivatives;
(b) stirring the mixture of step (a) to form precipitate;
(c) filtering and drying the precipitate of step (b), and optionally
(d) dissolving the dried precipitate of step (c) in a solvent and adding p-
toluenesulfonicacid to the solution to obtain the compound of general
formula A.
A still further embodiment of the present invention, the yield of the compound is in the range of 65% to 85%.
Yet another embodiment of the present invention, the derivatives of piperazine used is N-methylpiperazine.
Still another embodiment of the present invention, wherein the derivatives of TCNQ used are selected from 7-pyrrolidino-7,8,8-tricyanoquinodimethane (PTCNQ), 7-(3-hydroxypyrrolidino)-7,8,8-tricyanoquinodimethane (HPTCNQ) and 7-(3, R(+)-hydroxypyrrolidino)-7,8,8-tricyanoquinodimethane(RHPTCNQ).
Yet another embodiment of the present invention, the solution containing tetracyanoquinodimethane (TCNQ) or its derivatives is obtained by dissolving tetracyanoquinodimethane (TCNQ) or its derivatives in acetonitrile.
Still another embodiment of the present invention, the solution containing tetracyanoquinodimethane (TCNQ) or its derivatives is kept warm at the time of adding piperazine or its derivatives.
Still further embodiment of the present invention, the reaction mixture is stirred at a temperature in the range of 30°C to 75°C.
Further embodiment of the present invention, the reaction mixture is stirred for time period in the range of 0.5 hr to 2.0 hrs to obtain the precipitate.
Further embodiment of the present invention, the precipitate is dissolved in acetonitrile and p-toluenesulfonicacid is added to this solution to obtain the compound of general formula
A.
Still further embodiment of the present invention, wherein the compound having general formula A with the substitution
(Formula Removed)

is prepared by mixing N-methylpiperazine to a warm acetonitrile solution containing TCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate thus formed to obtain said compound.
Yet another embodiment of the present invention, wherein the compound having general formula A with the substitution
(Formula Removed)
is prepared by mixing N-methylpiperazine to a warm acetonitrile solution containing PTCNQ, stirring the reaction mixture till formation of precipitate and filtering the precipitate thus formed and drying the same to obtain said compound.
Still another embodiment of the present invention, wherein the compound having general formula A with the substitution
(Formula Removed)
is prepared by mixing piperazine with a warm acetonitrile solution containing HPTCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate thus formed to obtain said compound.
Yet another embodiment of the present invention, wherein the compound having general formula A with the substitution
(Formula Removed)
is prepared by mixing piperazine with a warm acetonitrile solution containing RHPTCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate formed to obtain said compound.
Yet another embodiment of the present invention, wherein the compound having general formula A with the substitution
(Formula Removed)
is prepared by mixing piperazine with a warm acetonitrile solution containing HPTCNQ, stirring the reaction mixture till formation of precipitate, filtering and drying the precipitate thus formed, dissolving the dried precipitate in acetonitrile and mixing the solution thus obtained with acetonitrile solution of p-toluenesulfonic acid to obtain microcrystalline precipitate, filtering and drying the microcrystalline precipitate thus formed to obtain said compound.
Yet another embodiment of the present invention, wherein the compound having general formula A with the substitution

(Formula Removed)
is prepared by mixing piperazine with a warm acetonitrile solution containing RHPTCNQ, stirring the reaction mixture till formation of precipitate, filtering and drying the precipitate thus formed, dissolving the dried precipitate in acetonitrile and mixing the solution thus obtained with acetonitrile solution of p-toluenesulfonic acid to obtain microcrystalline precipitate, filtering and drying the microcrystalline precipitate thus formed to obtain said compound.
The present invention also provides a polymeric substrate incorporated with remote functionalized DADQs for use in manufacturing vapor responsive switches and sensors,

said polymeric substrate comprising 98.7 to 99.2 wt % of a polymer and 1.3 to 0.8 wt % of the remote functionalized DADQs of the general formula A and wherein the polymer used has substantially different solubility factor as compared to DADQs with respect to at least one solvent.
In still another embodiment of the present invention, the polymer used is selected from polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS).
In one other embodiment of the present invention, wherein the doped polymer used has enhanced fluorescence in dry state and reduced fluorescence in presence of organic solvent vapours.
In one more embodiment of the present invention, wherein reduction in fluorescence of the doped polymer is triggered by presence of chloroform.
In yet another embodiment of the present invention, the reduction in fluorescence of the doped polymer in the presence of the solvent is reversible.
In yet another embodiment of the present invention, the reduction in fluorescence of the doped polymer in the presence of the solvent is reproducible.
In a further embodiment of the present invention, the doped polymer comprises 0.8 to 1.3 wt % of remote functionalized DADQ's of the general formula A and 99.2 to 98.7 wt % PVA polymer.
In a further embodiment of the present invention, the doped polymer comprises 0.8 to 1.3 wt % of remote functionalized DADQ's of the general formula A and 99.2 to 98.7 wt % PSS polymer.
In an embodiment of the present invention, the PVA polymer used has average molecular weight of 15,000.

In another embodiment of the present invention, the PSS polymer used has average molecular weight of 70,000.
In one more embodiment of the present invention, wherein the ratio of the fluorescence intensity of the said compounds in polymeric substrate to the fluorescence intensity of the compounds in acetonitrile solution is in the range of 20 to 220.
In one another embodiment of the present invention, wherein the ratio of the fluorescence intensity of the said compounds in PSS film to the fluorescence intensity of the same compounds in acetonitrile solution is in the range of 20 to 140.
The present invention further provides a process for preparing a polymeric substrate incorporated with remote functionalized DADQ's (doped polymers), said process comprising the steps of:
a) mixing 0.8 to 1.3 wt% of the said compound of general formula A in 99.2
to 98.7 wt% of the polymer, and
b) casting the mixture of step (a) to the required shape using any of the
conventional processes and drying the cast film to obtain the doped
polymer.
Still another embodiment of the present invention, the casting of reaction mixture is carried out by spinning process.
Yet another embodiment of the present invention, wherein drying is carried out for time period in the range of 1 hrs to 2 hrs.
Yet another embodiment of the present invention, wherein polymer is selected from polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS).

Remote functionalised DADQ's are new molecules having remote groups attached to the DADQ, which facilitate novel molecular assemblies without perturbing the chromophore properties and impart a number of interesting characteristics to DADQs. The remote functionalized DADQs can be used in several applications such as (i) steering centrosymmetric crystal lattice into SHG active noncentric ones, (ii) instance o f charge transfer phenomenon exclusively in the solid state and (iii) fabrication of desired molecular environment of interest in modeling studies.
A very important advantage derived from the presence of remote functionality on the DADQ's is the solubility of the compounds in water in addition to regular organic solvents. DADQ's which are not remote functionalized are generally either insoluble in water or undergo hydrolytic decomposition in water. Since the synthesized remote functionalized DADQ's are soluble in water and form stable aqueous solution, they can be incorporated in water soluble polymers. This allows the fabrication of doped polymer films which can be used for organic vapour sensing. Finally the remote functionality on the DADQs allows intermolecular interactions which appear to be important for the molecular aggregation and fluorescence enhancement.
The spectroscopic data on the new remote functionalized DADQ's allow to quantify the fluorescence enhancement in solid state and doped polymer films. None of the earlier studies on DADQs have demonstrated the type of reversibility and stability of fluorescence switching of the fluorescence on exposure to solvent or solvent vapors that the Applicants have demonstrated with doped polymer films containing the remote functionalized DADQ's.
None o f the e arlier D ADQs are known t o b e w ater-soluble a nd forming s table a queous solutions and the Applicants have been able to prepare remote functionalized DADQs that are water-soluble and stable in aqueous solution for the first time. Finally, the detailed modeling the Applicants have carried out for the mechanism of fluorescence enhancement is not available in the case of any of the systems reported earlier. The mechanism for the fluorescence enhancement in the remote functionalised DADQ's has been worked out with

the aid of semiempirical quantum chemical computations. The concept of 'molecule-in-a-crystal' developed earlier by the Applicants was utilized. Semiempirical AMI computations incorporating the solvation modeling routine, COSMO showed that the fluorescence observed arise from the vertical excited state. The computations showed that the geometry relaxed excited state would not show fluorescence in the visible range. Geometry relaxation is possible in solution, but unlikely in the solid state and in doped polymer films. Therefore, it is concluded that the fluorescence enhancement observed in the latter cases arises due to effective inhibition of the geometry relaxation. This mechanism is quite different from that proposed in the earlier systems.
When an optical property such as fluorescence (light emission) is affected reversibly by the presence or absence of a vapour; it can be an effective way to sense the vapour. Alternately the vapour can be used to switch on or off the optical signal and in this sense, the material can be used as a transducer where the vapour is the stimulus and optical signal is the response. Both these applications require that the process happens reversibly and reproducibly, Finally, polymer films have an important advantage that they can be produced cheaply and can be fabricated for large area coverage. This allows the sensing or switching element to be prepared economically. Doped polymer films allow fine control of dopant concentration and therefore, the optical response can be fine tuned based on the application needs.
BRIEF DESCRIPTION OF FIGURES:
1. Fig 1 shows the general formula of remote functionalized DADQ's.
2. Fig.2 s hows t he molecular s tructure (from crystal structure analysis) o f so me o f t he
remote functionalized DADQs as synthesized in the present invention.
3. Fig.3 depicts the variation of emission maximum of PVA film incorporated with
DADQ in presence and absence of chloroform vapor.
Figure 2 shows the molecular structure of the remote functionalized DADQ in the crystalline state for the DADQs with the substitutions as shown in options 1 and 2 for A.

Crystal structure analysis is possible only when large enough single crystals can be grown. The general structure is indicated for these and all other compounds in Fig. 1.
Figure 3 describes the phenomenon of the variation of the fluorescence emission maximum of doped polymers in presence/absence of chloroform vapor. In the dry state, the fluorescence is high (the filled square marks in the graph). On exposure to chloroform vapors, the fluorescence decreases (the filled circle marks in the graph). Both fluorescence are visible to naked eye under ambient lighting which has a UV (ultra-violet) component. However, the fluorescence in the dry state is, of course, more visible. The fluorescence is best observed using 350-360 nm light from a UV lamp for excitation.
Table 1 provides the wavelength (denoted by Greek letter lambda, expressed in nanometers, nm) of light at which each of the compound absorbs most, when in solution, in the solid state and when doped in polymer films (the superscript for lambda, abs, indicates this). The table also provides the wavelength where the fluorescence (same as emission) in each of these states is maximum for each of the compound (the superscript for lambda, em, indicates this). R is the ratio of the fluorescence intensity in the solid state or polymer film, compared to the fluorescence intensity of the same compound in acetonitrile solution. This number indicates the enhancement of fluorescence in the solid state and polymer film, compared to the solution state.
Table 1. Visible absorption (λ maxabs) and emission (λ maxem) peaks of 1 - 6 in acetonitrile solution, solid state and in PV A and PSS films and the fluorescence enhancement, R of the solid and polymer films over that in acetonitrile solution.

(Table Removed)

WE CLAIM:
1. Remote functionalised Diaminodicyanoquinodimethanes (DADQs) having enhanced fluorescence in the solid state and reduced fluorescence in presence of organic solvent (ie. in solution or for the doped polymer film, in presence of solvent vapours), having general formula A:

(Formula Removed)
Wherein:
(Formula Removed)
2. Remote functionalized DADQs as claimed in claim 1, wherein reduction in
fluorescence of the compound is triggered by presence of an organic solvent.
3. Remote functionalized DADQs as claimed in claim 1, wherein the reduction in
fluorescence of the compound is triggered by presence of the solvent is a reversible
process.
4. Remote functional ized DADQs as claimed in claim 1, wherein the organic solvent
is chloroform.
5. Remote functionalized DADQs as claimed in claim 1, wherein the ratio of the
fluorescence intensity of the compound in solid state to the fluorescence intensity
of the compound in presence of Acetonitrile solution is in the range of 20 to 350
220.
6. Remote functionalized DADQs as claimed in claim 1, wherein if the substitution is
the compound has the following characteristics: M.P. = 278-280°C (dec); FTIR
(Formula Removed)
(KBr): v/cm-1 = 2172.0, 2135.4, 1595.3, UV-Vis (acetonitrile): λma/nm = 269,420; 'H-NMR (CDC13): δ/ppm = 1.7 (s, 6H, 2.6-2.7 (m, 8H), 3.5-3.6 (m, 8H), 7.1 (s, 4H); 13C-NMR ([D6]DMSO) : 8 /ppm = 34.5, 45.5, 50.9, 54.6, 114.1, 118.1, 123.2,131.8,149.8, 168.8; anal. (calc. for C2oH26N6): % C = 68.31 (68-57), %H -7.11 (7.43), %N = 24.61 (24,00), maximum absorption and emission intensity in solid state takes place at 422 nm and 492 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 420 nm and 543 nm respectively.
7. Remote functional ised DADQs as claimed in claim 1, wherein if the substitution is the compound has the following characteristics: M.P. = 260-262°C (dec); FTIR

(Formula Removed)
(KBr) : v/cm'1 = 2941.7, 2170.1, 2133.5, 1595.3, UV-Vis (acetonitrile): λmax /nm = 267,407;'H-NMR (CDC13): δ/ppm = 1.6 (s, 3H), 2.0 to 2.11 (t, 4H), 2.15-2.25 (t, 4H), 3.5-3.6 (t, 4H), 3.60-3.75 (t, 4H), 7.0 (s, 4H); 13C-NMR ([D6]DMSO) : 8 /ppm = 24.1, 25.7, 33.1, 45.5, 50.1, 52.7, 54.6, 115.2, 118.1, 123.7, 130.5, 148.3,165.9; anal. (calc. for C19H23N5): %C = 70.93 (71.03), %H - 7.22:(7.71), %N
= 21.72 (21.80); maximum absorption and emission intensity in solid state takes place at 422 nm and 495 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 407 nm and 538 nm respectively.
8. Remote functionalised DADQs as claimed in claim 1, wherein if the substitution is the compound has the following characteristics M.P.=245-246°C (dec); FTIR
(Formula Removed)
(KBr) : v/cm'1 = 3390.0, 2170.1, 2131.5, 1597.2; UV-Vis(acetonitrile) : λma/nm = 273, 407; 1H-NMR([D6]DMSO): δ /ppm=1.9-2:l(m,3H), 2.75-2.90 (m, 4H), 3.7-3.8 (m, 4H), 4.3-4.4 (m, 4H), 5.3(s, 1H), 6.8-6.9(d, 2H), 7.15-7.20 (d, 2H), hydroxy proton was not observed; 13C-NMR ([D6]DMSO): 8/pprn^= 32.5, 33.1, 34.2, 46.1, 50.6, 51.8, 60.3, 67.6, 69.1, 115.1, 118.1, 123.8, 130.6, 148.3, 166.5; anal. (calc. for C18H21N5O): %C = 66.86 (66.87), %H = 6.49 (6.50), %N = 21.68 (21.67); maximum absorption and emission intensity in solid state takes place at 4 19 nm and 534 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 407 nm and 533 nm respectively.
9. Remote functionalised DADQs as claimed in claim 1, wherein if the substitution is the compound has the following characteristics M.P.= 213-215°C (dec); FTIR

(Formula Removed)
(KBr) : v/cm'1 = 3308.0, 2170.0, 2131.0, 1597.0; UV-Vis (acetonitrile): λma/ nm = 270, 408; 'H-NMR([D6]DMSO): δ /ppm=1.8-2.1(m,3H), 2.7-2.9 (m, 4H), 3.6-3.9 (m, 4H), 4 .2-4.5 (t, 4H), 5 .3 (s, 1 H), 6 .8-6.9 (d, 2H), 7 .2-7.35 (d, 2H), hydroxy proton was not observed; I3C-NMR (D6DMSO) 5/ppm=32.2, 33.0, 34.3, 46.0, 50.6, 51.7, 60.3, 68.0, 69.1, 115.1, 118.1, 123.8, 130.6, 148.3, 166.5; anal (calc. for C18H21N5O): %C - 66.22 (66.87), %H = 6.85 (6.50), %N = 21.68 (21.67);

maximum absorption and emission intensity in solid state takes place at 410 nm and 553 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 408 nm and 539 nm respectively.
10. Remote functional ised DADQs as claimed in claim 1 , wherein if the substitution is

(Formula Removed)
the compound has the following characteristics M.P.= 250-255°C(dec);FTIR (KBr): v/cm'=3398.2, 3022.8, 2177.8, 2137.0, 1597.0, 1005.0, 887.0, 814.0; UV-Vis (acetoajtrile): λmax/nm-267, 422; 'H-NMR ([D6]DMSO): 8 /ppm = 1.9-2.0 (m, 3H), 2.1-2.2 (m, 4H), 2.3(s,3H), 3.8-4.0(m,4H), 4.30-4.45 (t, 2H), 5.25-5.40 (m, 2H), 6.8-6.9 (m, 2H), 7.1-7.2(d,2H),7.3-7.4(m,2H), 7.5-7.6 (d, 2H), 8.85-9.15 (s, 2H), hydroxy proton was not observed; I3C-NMR([D6]DMSO) : δ /ppm = 21.0, 32.5, 33.3, 34.0, 43.1, 44.7, 49.7, 50.8, 60.1, 60.6, 67:5, 69.1, 1 14.7, 1 18.1, 123.7, 125.7, 128.4, 130.7, 138.2, 145.5, 148.5, 167.0, the extra peaks appear to result from clustering of the zwitterionic molecules, since their reproducibility was verified by repeated purification and the absence of impurities was further confirmed by the satisfactory elemental analysis; anal. (calc. for C25H29NSO4 : %C = 60.62 (60.61), %H = 5.89 (5.86), %N = 14.24 (14.14); maximum absorption and emission intensity in solid state takes place at 418 nm and 518 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 422 nm and 540 nm respectively.
Remote functional ised DADQs as claimed in claim 1, wherein if the substitution is

(Formula Removed)
the compound has the following characteristics M.P.= 239-244°C (dec); FTIR
(KBr):v/cm'=3362.2, 3015.0, 2177.8, 2137.3, 1597.2, 1005.0, 887.3, 814.0; UV-Vis (acetonitrile): λ max /nm = 265,408;'H-NMR ([D6]DMSO): δ/ppm =1.9-2.0 (m, 3H), 2.1-2.2 (m,4H), 2.3(s,3H), 3.6-3.9 (m, 4H), 4.25-4.45 (m, 2H), 5.25-5.40

(m, 2H), 6.8-6.9 (m, 2H), 7.1-7.2(d,2H),7.25-7.4 (m, 2H), 7.5-7.6 (d, 2H), 8.8-9.2 (s, 2H), hydroxy proton was not observed; 13C-NMR ([D6]DMSO) :δ/ppm = 21.0, 32.6, 33.7, 34.1, 43.0, 47.1, 50.7, 51.3, 60.0, 61.0, 67.6, 69.3, 114.5, 118.1, 123.6, 125.7, 128.4, 130.9, 138.4, 145.2, 148.8, 166.7, the extra peaks appear for the same reasons as described under 11; anal. (calc. for C25H29N5SO4):%C = 60.55 (60.61), %H = 5.93 (5.86), %N = 14.21 (14.14); maximum absorption and emission intensity in solid state takes place at 403 nm and 531 nm respectively, maximum absorption and emission intensity in acetonitrile solution takes place at 408 nm and 536 nm respectively.
12. A process for preparing the remote functionalised Diaminodicyanoquinodimethanes (DADQs) having general formula A:
(Formula Removed)
wherein:
(Formula Removed)
said process comprising the steps of:
a. adding piperazine or its derivatives to a solution containing
tetracyanoquinodimethane (TCNQ) or its derivatives;
b. stirring the mixture of step (a) to form precipitate;
c. filtering and drying the precipitate of step (b), and optionally
d. dissolving the dried precipitate of step (c) in a solvent and adding p-
toluenesulfonicacid to the solution to obtain the compound of general formula A.
13. A process as claimed in claim 12, wherein the yield of the compound is in the range
of 65% to 85%.
14. A process as claimed in claim 12 wherein in step (a), the derivatives of piperazine
used is N-methylpiperazine.
15. A process as claimed in claim 12 wherein in step (a), the derivatives of TCNQ used
are selected from 7-pyrrolidino-7,8,8-tricyanoquinodimethane (PTCNQ), 7-(3-
hydroxypyrrolidino)-7,8,8-tricyanoquinodimethane (HPTCNQ) and 7-(3, R(+)-
hydroxypyrrolidino)-7,8,8-tricyanoquinodimethane(RHPTCNQ).
16. A process as claimed in claim 12 wherein in step (a), the solution containing
tetracyanoquinodimethane (TCNQ) or its derivatives is obtained by dissolving
tetracyanoquinodimethane (TCNQ) or its derivatives in acetonitrile.
17. A process as claimed in claim 12 wherein in step (a), the solution containing
tetracyanoquinodimethane (TCNQ) or its derivatives is kept warm at the time of
adding piperazine or its derivatives.
18. A process as claimed in claim 12 wherein in step (b), the reaction mixture is stirred
at a temperature in the range of 30°C to 75°C.
19. A process as claimed in claim 12 wherein in step (b), the reaction mixture is stirred
for time period in the range of 0.5 hr to 2.0 hrs to obtain the precipitate.
20. A process as claimed in claim 12 wherein in step (d), the precipitate is dissolved in
acetonitrile and p-toluenesulfonicacid is added to this solution to obtain the
compound of general formula A.
21. A process as claimed in claim 12, wherein the compound having general formula A
with the substitution
(Formula Removed)
is prepared by mixing N-methylpiperazine to a warm acetonitrile solution containing TCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate thus formed to obtain said compound.
22. A process as claimed in claim 12, wherein the compound having general formula
A with the substitution
(Formula Removed)
is prepared by mixing N-methylpiperazine to a warm acetonitrile solution containing PTCNQ, stirring the reaction mixture till formation of precipitate and filtering the precipitate thus formed and drying the same to obtain said compound.
23. A process as claimed in claim 12, wherein the compound of general formula A with the substitution:

(Formula Removed)
is prepared by mixing piperazine with a warm acetonitrile solution containing HPTCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate thus formed to obtain said compound.
24. A process as claimed in claim 12, wherein the compound of general formula A with the substitution:
(Formula Removed)
is prepared by mixing piperazine with a warm acetonitrile solution containing RHPTCNQ, stirring the reaction mixture till formation of precipitate and filtering and drying the precipitate formed to obtain said compound.
25. A process as claimed in claim 12, wherein the compound of general formula A with the substitution:

(Formula Removed)
is prepared by mixing piperazine with a warm acetonitrile solution containing HPTCNQ, stirring the reaction mixture till formation of precipitate, filtering and drying the precipitate thus formed, dissolving the dried precipitate in acetonitrile and mixing the solution thus obtained with acetonitrile solution of p-toluenesulfonic acid to obtain microcrystalline precipitate, filtering and drying the microcrystalline precipitate thus formed to obtain said compound.
26. A process as claimed in claim 12, wherein the compound of general formula A with the substitution:

(Formula Removed)
is prepared by mixing piperazine with a warm acetonitrile solution containing RHPTCNQ, stirring the reaction mixture till formation of precipitate, filtering and drying the precipitate thus formed, dissolving the dried precipitate in acetonitrile and mixing the solution thus obtained with acetonitrile solution of p-toluenesulfonic acid to obtain microcrystalline precipitate, filtering and drying the microcrystalline precipitate thus formed to obtain said compound.

27. A polymeric substrate incorporated with remote functionalized DADQs as claimed
in claim 1 (doped polymer), for use in manufacturing vapor responsive switches
and sensors, said doped polymer comprising 98.7 to 99.2 wt % of a polymer and
1.3 to 0.8 wt % of the remote functionalized DADQs of claim 1 and wherein the
polymer used has substantially different solubility factor as compared to DADQs
with respect to at least one solvent.
28. A doped polymer as claimed in claim 27, wherein the polymer used i s selected
from polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS).
29. A doped polymer as claimed in claim 27, wherein the doped polymer has enhanced
fluorescence in dry state and reduced fluorescence in presence of organic solvent
vapours.
30. A doped polymer as claimed in claim 29, wherein reduction in fluorescence of the
doped polymer is triggered by presence of chloroform.
31. A doped polymer as claimed in claim 29, wherein the reduction in fluorescence of
the doped polymer, in the presence, of the solvent is reversible.
32. A doped polymer as claimed in claim 29, wherein the reduction in fluorescence of
the doped polymer, in the presence of the solvent is reproducible.
33. A doped polymer as claimed in claim 28, wherein the doped polymer comprises
99.2 to 98.7 wt % of PVA polymer and 0.8 to 1.3 wt % of DADQs of the general
formula A.
34. A doped polymer a s claimed in claim 28, wherein the doped olymer c omprises
99.2 to 98.7 wt % of PSS polymer and 0.8 to 1.3 wt % of DADQ's of the general
formula A.
35. A doped polymer as claimed in claim 28, wherein PVA polymer used has average
molecular weight 15,000.

36. A doped polymer as claimed in claim 28, wherein PSS polymer has average
molecular weight 70,000.
37. A doped polymer as claimed in claim 28, wherein the ratio of the fluorescence
intensity of the said compounds in polymeric substrates the fluorescence intensity
of the said compounds in acetonitrile solution is in the range of 20 to 220.
38. A doped polymer as claimed in claim 28, wherein the ratio of the fluorescence
intensity of the said compounds in PSS film or PVA film to the fluorescence
intensity of the said compounds in acetonitrile solution is in the range of 20 to 140.
39. A process for preparing of polymeric substrate incorporated with remote
functionlised DADQ's (doped polymer) as claimed in claim 29, said process
comprising the steps of:
a. mixing 0.8 to 1.3 wt% of the said compound of general formula A as
claimed in claim 1 with 99.2 to 98.7 wt% of the polymer, and
b. casting the mixture of step (a) to the required shape using any of the
conventional processes and drying the cast film to obtain the doped
polymer.
40. A process as claimed in claim 41 wherein in step (a), polymer is selected from
polyvinyl alcohol (PVA) and polystyrene sulfonate (PSS).
41. A process as claimed in claim 41 wherein in step (b), casting of mixture is carried
out by spinning process.
42. A process as claimed in claim 41 wherein in step (b), drying is carried out for time
period in the range of 1 hrs to 2 hrs.
43. Remote functionalised Diaminodicyanoquinodimethanes (DADQs) having
enhanced fluorescence in the solid state and reduced fluorescence in presence of
organic solvent, substantially as herein described and illustrated therein.

44. A process for preparing the remote functionalised
Diaminodicyanoquinodimethanes (DADQs) having general formula A,
substantially as herein described and illustrated therein.
45. A polymeric substrate incorporated with remote functionalized DADQs,
substantially as herein described and illustrated therein.
46. A process for preparing of polymeric substrate incorporated with remote
functionlised DADQ's (doped polymer), substantially as herein described and
illustrated therein.

Documents:

1431-del-2003-abstract.pdf

1431-del-2003-claims.pdf

1431-del-2003-correspondence-others.pdf

1431-del-2003-correspondence-po.pdf

1431-del-2003-description (complete).pdf

1431-del-2003-drawings.pdf

1431-del-2003-form-1.pdf

1431-del-2003-form-19.pdf

1431-del-2003-form-2.pdf

1431-del-2003-form-26.pdf

1431-del-2003-form-3.pdf

1431-del-2003-form-5.pdf

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Patent Number

218381

Indian Patent Application Number

1431/DEL/2003

PG Journal Number

19/2008

Publication Date

09-May-2008

Grant Date

31-Mar-2008

Date of Filing

18-Nov-2003

Name of Patentee

UNIVERSITY OF HYDERABAD

Applicant Address

SCHOOL OF CHEMISTRY HYDERABAD 500046 INDIA

Inventors:

#	Inventor's Name	Inventor's Address
1	SUBBALAKSHMI JAYANTY	SCHOOL OF CHEMISTRY UNIVERSITY OF HYDERABAD HYDERABAD 500046 INDIA.
2	THAVAROOL PUTHIYEDATH RADHAKRISHNAN	SCHOOL OF CHEMISTRY UNIVERSITY OF HYDERABAD : 500046 INDIA .

PCT International Classification Number

C07C

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA