Furyl-Substituted Mixed Phosphonium-Iodonium Ylides in the Synthesis of Annelated P-Containing Heterocyclic Compounds

摘要

Photochemical reactions between stabilized furyl-substituted phosphonium-iodonium ylides and terminal acetylenes led to the formation of new P-containing heterocyclic compounds. For the heterocyclization of 2-furyl-substituted ylides, we observed an unprecedented electrophilic ipso attack onto the alpha position of the furan ring in a carbocationic intermediate, leading - via a spiro intermediate - to the rearranged product with a 2,3-shift in the furan ring.