Process for preparing 3,4-dihydro-2(1H)-quinazolinone derivatives

摘要

3,4-Dihydro-2(1H)-quinazolinones and quniazolinethiones such as 1-cyclopropylmethyl-4-phenyl-6-methoxy-3,4-dihydro-2(1H)-quinazolinone and its thione derivative, are prepared in high yield with high purity by heating the corresponding arylurea or thiourea such as N-cyclopropylmethyl-N-(p-methoxyphenyl) urea or its thiourea derivative, with the corresponding aldehyde such as benzaldehyde in the presence of hydrobromic acid in an inert solvent.