THE REACTION OF PHTHALIDYLIDENE DICHLORIDE WITH PRIMARY AMINES - SYNTHESIS AND X-RAY MOLECULAR-STRUCTURE OF N-SUBSTITUTED PHTHALISOIMIDES

An efficient method for the synthesis of N-substituted phthalisoimides , by reaction of phthalidylidene dichloride with primary amines, is de scribed. The reactions with arylamines, arylenediamines and alkylenedi amines lead to the corresponding phthalisoimides or bisphthalisoimides in nearly quantitative yields. However, the reactions with alkylamine s are not useful because of the relatively high nucleophilicity of alk ylamines. Certain particular behaviours of arylamines, associated with the presence of specific ortho-substituents have been found. The reac tions of arylamines bearing an o-hydroxymethyl group provide a conveni ent method for preparing 2-benzoxazinylbenzoic acids. The X-ray crysta llographic structures of N-(2-methoxyphenyl)phthalisoimide 3a and 2-(4 H-3,1-benzoxazin-2-yl)benzoic acid 15a have been determined. (C) 1997 Elsevier Science Ltd.