Synthesis of 2-(4-quinazolinyl)ethyl sulfides via addition of thiols to 4-vinylquinazolines

Reaction of vinyl and isopropenyl Grignard reagents with quinazoline results in addition to the 3,4‐imine bond to give the 4‐alkenyldihydroquinazolines 4 which are conveniently aromatized with potassium ferri‐cyanide to the 4‐alkenylquinazolines 5. Quinazolines 5 undergo addition with thiols under neutral conditions to afford the quinazolinylethyl sulfides 2 in moderate yields.