Novel Tandem Three Consecutive Reactions: Aza-Wittig, Imine Condensation and Electrophilic Aromatic Substitution Strategy to Indolizine Synthesis

Reaction of ethyl (Z)-3-(heteroaryl/aryl)-2-((triphenyl-λ5-phosphaneylidene) amino) acrylates intermediates with 2,3-thiophenedicarboxaldehyde was used in novel Tandem three consecutive reactions: aza-Wittig, imine condensation and electrophilic heteroaromatic cyclization to obtain a series of indolizines. A tentative mechanism of this reaction is proposed.