Synthesis of 1-Acyl-3,4-dihydroquinazoline-2(1H)-thiones by Cyclization of N-[2-(Isothiocyanatomethyl)phenyl] Amides Generated in situ from N-[2-(Azidomethyl)phenyl] Amides

摘要

An efficient method for the preparation of 1-acyl-3,4-dihydroquinazoline-2(1H)-thiones 5 has been developed. The reaction of N-[2-(azidomethyl)phenyl] amides 3, easily prepared by a three-step sequence starting with (2-aminophenyl)methanols, with Ph3P, followed by CS2, allowed generation of N-[2-(isothiocyanatomethyl)phenyl]-amide intermediates 4, which underwent cyclization on treatment with NaH to furnish the corresponding desired products in generally good yields.