Process for preparing 2,4-dihaloquinazolines

摘要

A one-step process for the preparation of 2,4-dihaloquinazolines is disclosed beginning with methoxycarbonyl- or phenoxycarbonyl-derivatives of substituted phenylureas which are cyclized and concomitantly halogenated with a cyclizing-halogenating reagent such as N,N-dimethylaniline in phosphorus oxychloride. The 2,4-dihaloquinazolines of the instant process are particularly valuable as intermediates in the preparation of 4-amino-2-(4-substituted-piperazin-1-yl) quinazolines useful in the treatment of cardiovascular disorders such as hypertension.