Title of Invention	A PROCESS FOR THE PREPARATION OF 7-DIETHYLAMINO-2H-1-BENZOPYRAN-2-OXE-3-(N-SUBSTITUTED)-CARBOXAMIDES’’
Abstract	A process for preparation of 7-diethylamino-2H-l-benzopyran-2-oxo-3-(N- substituted)-carboxamides by refluxing 4 - diethylamino salicylaldehyde and malonic esters of aromatic amines in methanol containing catalytic amount of piperidine is disclosed.

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FORM 2 The Patents Act, 1970 [39 of 1970] Complete Specification [See section 10] 1. "A PROCESS FOR THE PREPARATION OF 7-DIETHYLAMINO-2H-l-BENZOPYRAN-2-OXO-3-(N-SUBSTITUTED)-CARBOXAMIDES" 2. (A) STRIDES ARCOLAB LTD. (B) 201, Devavrata, Sector 17, Vashi, Navi Mumbai - 400 703, India (C) Nationality - Indian The following specification particularly describes and ascertains the nature of this invention and the manner in which it is to be performed:- A PROCESS FOR THE PREPARATION OF 7-DIETHYLAMINO-2H-1-BENZOPYRAN-2-OXO-3-(N-SUBSTITUTED)-CARBOXAMIDES The present invention relates to a novel process for producing the title compound 7-diethylamino-2H-l-benzopyran-2-oxo-3-(N-substituted)-carboxamides from 4-salicylaldehyde and malonic esters of aromatic amine, with the use of the suitable solvent and specific compounds as catalyst. The process herein described is particularly beneficial for commercially manufacture of compound. Background of the Invention The title compound 7-diethylamino-2H-l -benzopyran-2-oxo-3-(N-substituted)-carboxamides which is a coumarin derivatives is widely applied as coumarin dyes as argon sensitisers for photopolymerization system and also use as a coumarin laser dyes are reported in some journals. The literature survey brought out various papers describing the series of the uses of coumarin dyes. Some of these processes that are relevant to the current invention are cited below. Title compound used for the photopolymerizable compositions featuring coinitiaters by Specht, Donald P; Houle, Conard G; Farid, Samis Y (Eastman Kodak Co.) U.S. 4,289, 844 (Cl. 430 - 281; GO3 Cl/ 68), 15 September 1981, appl. 49661, 18th June 1979; 16 Pp. Coumarin derivatives were studied as prospective laser dyes in the stabilization against photodecomposition, by Komlev I. V; Tavrizova. M. A; Khrolova O. R; Mikhailova T. A. (Hauchno - Issled. Inst. Org. Poluprod. Krasitelei, Mascow, USSR) 2h. Obshch. Khim. 1985, 55 (4), 888 - 92 (Russ). Spectroscopic studies of photoreaction in aminocoumarin derivatives used as a photostable laser coumarin dyes by Squamsonova, L. G; Fofonova R. M.; Kuznetsova R. T.; Sokolova I.V.; Loboda L.I.; Vasileva N. Yu.; Ivanova. E. V. 1 Khochkina. O. I. (Sib. Fiz - Tekh. Inst. ; Tomsk, Russia). Kvantovaya Elektron (Kiev) 1992,41, 63-72 (Russ). Study of complexation with cyclodextrins a new ways of increasing the stability of coumarin laser dyes against singlet oxygen, by Kalmykova E. A. ; Kuznetsova N. A.; Kaliya 0. L.; Zinkovskaya Elektron (Kiev) 1992, 41,102 - 6 (Russ). Study of simplified spontaneous emission characteristics of LD473 and coumarin 102 laser dyes; by Sastikumar D.; Masilamani V. (Dep. Physics, Regional Engineering College, Tiruchirappali, 620015 India) Indian J. Chem. Soct A; Inorg, Bio - inorg; Phys; Theor. Anal Chem. 1998, 37 A (2) 151 - 154 (Eng). Coumarin derivatives present as a one of the most important chemical classes of organic fluorescent materials through the investigation of the electronic spectral properties of the substituted coumarin by Christie, Robert M, Lui Chih - Hung. (School of Textiles, Heriot Watt University, Galashiels, UK TDI 3HF) Dyes Pigm. 1999,42 (l),85-93 (Eng.) There are also known processes that are available for the preparation of the title compound, 7-diethylamino-2H-l-benzopyran-2-oxo-3-(N-substituted)-carboxamides. Those known methods represent processes for the synthesis of the said compound which is viable for laboratory preparation, however when it comes to commercial application, we find there is some limitation that all are multi-step processes, which are laborious as consume more time and man power as well as involving high cost also . The current invention describes a process that explores the possibility of developing a cheaper, one pot reaction and industrially viable process for the large scale manufacture of the compound . 2 The title compound is a synthesized coumarin dye -substituted polymers that have delocalized pi- electron system, in turn capable of exhibiting non-linear optical response. Those dye-substituted polymers have several distinct advantages over guest-host materials including higher limiting concentration of the chromophore, reduced mobility and enhanced orientational stability of the chromophore as well as improved optical, thermal and mechanical properties. Description of the Invention According to the present invention a process has been developed whereby 7-diethylamino-2H-l-benzopyran-2-oxo-3- (N-subtiruted)-carboxamides, is prepared by the experimental as described below: Experimental Charged equimolar quantities of 4 - diethylamino salicylaldehyde, malonic esters of aromatic amines in methanol containing catalytic amount of piperidine, reaction mixture refluxed till completion of reaction. Reaction was monitored by TLC. After completion of the reaction, mixture cooled to 5 - 10°c. Separated crystals filtered in good yield (70%). Reaction Scheme The following reaction scheme further illustrates and describes the process particularly described herein. 3 4 5 We Claim: 1. A process for preparing 7-diethylamino-2H-l -benzopyran-2-oxo-3-(N-substituted) carboxamides wherein said process consists of. condensing 4-diethylamino salicylaldehyde and malonic esters of aromatic amines in methanol in presence of a catalytic amount of piperidine, and cooling the resultant reaction mixture to 5-10°c. 2. The process according to claim 1, wherein said carboxamide is 4- amino benzanilide. 3. The process according to claim 1, wherein the said carboxamide is 2- amino-1, 3,4-thiadiazole. 4. The process according to claim 1, wherein the said carboxamide is 2- amino-5-methyl-l, 3,4-thiadiazole. 5. The process according to claim 1, wherein the said carboxamide is 4'- methoxy-3 '-trifluoro methyI-3-amino-1 -benzanilide. 6. The process according to claim 1, wherein the said process for preparing 7-diethyIamino-2H-l-benzopyran-2-oxo-3-(N-substituted) carboxamide is a one pot preparation process. 7. The process according to claim 1, wherein the said reaction is monitored by TLC. 8. The invention as substantially herein described with reference to the experimental. 6

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1127-mum-2001-abstract(26-11-2001).doc

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1127-mum-2001-abstract(ameneded)-(24-5-2004).pdf

1127-mum-2001-abstract(granted)-(15-12-2005).doc

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1127-mum-2001-claims(ameneded)-(24-5-2004).pdf

1127-mum-2001-claims(granted)-(15-12-2005).doc

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1127-mum-2001-correspondence(27-2-2006).pdf

1127-mum-2001-correspondence(ipo)-(23-1-2004).pdf

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