Preparation of isoindolo[2,1-a]quinoxalines based on n-(2-aminophenyl) isoindole derivatives

摘要

A new method is proposed for the preparation of N-(2-aminophenyl)isoindoles by the reaction of o-(bromomethyl)benzophenones with 1,2-phenylenediamines. The reaction of N-(2-aminophenyl)isoindoles with Ac_2O leads to 1,N-diacetyl- or 1,N,N-triacetyl derivatives, whereas heating with formic acid or diethyl oxalate leads to cyclization with the formation of 11-arylisoindolo[2,1-a]quinoxaline derivatives. Salt formation in the 11-arylisoindolo[2,1-a]quin-oxaline series was studied.