Catalyst-free synthesis of 2-aryl-1,2-dihydro-quinazolin-4(1H)-thiones from 2-aminobenzothio-amides and aldehydes in water

Abstract

2-Dihydroquinazolin-4(1H)-thiones were prepared in up to excellent yields from 2-aminobenzothioamides and aldehydes. The reaction is carried out in water without the use of any catalyst or promoter. The sulfur-containing substrate can be obtained easily by thiation of the corresponding nitrile by solid sodium hydrosulfide.