Synthesis of Heteroaryl Enones for Ir(III) Catalyzed 1,2-H Shift/ Friedel-Crafts Alkylation

The Synthesis of heteroaryl enones for the Ir(III) catalyzed 1,2-H shift/ Friedel-Crafts Alkylation sequence was reported. It had been a long while that Nazarov cyclization was performed to form a five membered ring of ketones via 4π-electron conrotatory closure. However, this mehod did not work for heteroaromatic enones. Though Scandium Triflate with lithium perchlorate can cyclize indole and pyrrole analogues and form five membered rings, furyl and benzofuryl enones remained uncyclized. Upon the new synthesis of an iridium complex [IrBr(CO)(DIM)((R)-(+)-BINAP)](SbF6)2 , it was found that the furyl and benzofuryl enones were cyclized in a different fashion. Instad of a five member ring, a six or seven member ring with a quaternary carbon center was formed when catalytic amount of irdium complex and silver hexafluoroantimonate was added to a furyl or bezofuryl enone. This poster discussed how these furyl or benzofuryl enones were prepared by two different pathways. Also, this poster presented the sucessfully prepared enones via these methods.