ChemInform Abstract: SYNTHETIC STUDIES ON QUINAZOLINE DERIVATIVES. I. FORMATION OF 2(1H)‐QUINAZOLINONES FROM THE REACTION OF 2‐TRIHALOACETAMIDOPHENYL KETONES WITH AMMONIA

Abstract

A series of 2-trihaloacetamidophenyl ketones was prepared. The 2-trichloro- or 2-tribromoacetamidophenyl ketones, in most cases, were readily converted to the corresponding 4-substituted 2 (1H)-quinazolinones by reaction with ammonia via loss of the trihalomethyl function. Treatment of 5-chloro-2-trichloroacetamidobenzophenone with ammonium acetate in dimethyl sulfoxide (method H) gave 6-chloro-4-phenyl-2 (1H)-quinazolinone in quantitative yield, whereas, under similar conditions, the 2-trifluoroacetamide derivative reacted to yield 6-chloro-4-phenyl-2-trifluoromethylquinazoline. In the case of the N-substituted derivative of 2-trichloroacetamidobenzophenones, the 4-phenyl-2H-3, 1-benzoxazin-2-ones or 2-aminobenzophenone imines were isolated depending on the reaction conditions. For the conversion of the N-substituted derivatives to the corresponding 2 (1H)-quinazolinones the best result was obtained by heating them with ammonium acetate in dioxane (method J). In the case of the trichloroacetanilides bearing an ethoxycarbonyl, cyano or hydrogen in the o-position, the corresponding cyclic or acyclic ureas were obtained by this reaction. Mechanisms for their formations are proposed.