Abstract

SYNTHESIS OF ISOCOUMARINS AND ISOQUINOLONES

Vijakumar L. Chavan* and Rajendra R. Rane

Abstract

5H-furo[2,3-c] [2]benzopyran-1,5(2H)-dione was synthesized accidentally in excellent yield while trying to synthesize 1H-furo[3,4- c][2]benzopyran-1,5(3H)-dione using a different method. The reaction of homophthalic anhydride was carried with chloroacetyl chloride using pyridine as a catalyst, followed by rearrangement of 4- (chloroacetyl)-1H-2-benzopyran-1,3(4H)-dione at high temperature. Further 4-(chloroacetyl)-1H-2-benzopyran-1,3(4H)-dione was converted to 3-(chloromethyl)-1-oxo-1H-2-benzopyran-4-carboxylic acid at room temperature. As an extension to this work 5H-furo[2,3-c] [2]benzopyran-1,5(2H)-dione was derrivatised to its respective Isoquinolones using ammonia and primary amines. Also the chemistry of 3-(chloromethyl)-1- oxo-1H-2-benzopyran-4-carboxylic acid has been studied.

Keywords: Isocoumarin, homophthalic anhydride, chloroacetyl chloride, pyridine, furo compound, isoquinolone