Synthesis of aryl-fused 1,4-oxathiepines from pyridinium 1,4-zwitterionic thiolates and vinylideneortho-quinone methides

Synthesis of aryl-fused 1,4-oxathiepines from pyridinium 1,4-zwitterionic thiolates with vinylidene ortho -quinone methides generated in situ via a formal (3 + 4) pathway.