Gold-Mediated Isomerization of Cyclooctyne to Ring Fused Olefinic Bicycles

Abstract

Isomerization reactions of cyclooctyne mediated by N-heterocyclic carbene supported gold(I) leading to ring-contraction and the formation of 5/5-fused bicyclic alkenes have been observed. Isolation and complete characterization, including X-ray structural data of the cationic gold(I) complexes featuring the precursor alkyne and the product alkenes are also described. Gold catalyzes the isomerization of cyclooctyne leading to alkenes featuring two fused five-membered rings.