6?-Elelctrocyclization of Azahexa-1,3-5-trienes: A New Entry to a Regiospecific Synthesis of 3-Aryl(heteroaryl)pyridines

Article abstract of DOI:10.1016/S0040-4020(01)87250-1

Aza Wittig reaction of iminophosphoranes derived from ethyl α-azido-β-aryl(pyrazolyl)propenoates with α,β-unsaturated aldehydes leads to aldimines which by heating undergo electrocyclic ring-closure throungh the 3-azahexa-1,3,5-triene moiety to give 3-ary