The reaction of α-substituted 2-isocyanostyrenes, which could
be readily prepared from commercially available 2-aminophenyl ketones
or 2-aminobenzonitriles, with sulfur in the presence of a catalytic
amount of selenium proceeded smoothly to give the corresponding
2-isothiocyanatestyrenes. The latter spontaneously underwent the
electrocyclic reaction to afford 4-substituted quinoline-2(1H)-thiones in one-pot with isolated yields
ranging from 37 to 91%.
quinoline-2(1H)-thiones - isocyanides - electrocyclic reaction - isothiocyanates - sulfur
