Recent Advances in the Enantioselective Gold-catalyzed Cycloisomerization of 1,6-Enynes toward Functionalized Oxa-, Aza-bicyclo [4.1.0]Hept-4-ene—Applications in Biology and Fragrances

This short review highlights recent advances in the enantioselective gold-catalyzed cycloisomerization of 1,6-enynes as an efficient strategy for accessing oxa- and aza-bicyclo[4.1.0]hept-4-enes as well as bicyclo[3.1.0] hexane derivatives. Emphasis is placed on the development of chiral gold catalysts and tailored substrate designs that enable high levels of chemo-, regio-, and stereocontrol despite the linear coordination geometry of gold(I). Mechanistic insights, including ligand effects and secondary interactions such as hydrogen bonding, are discussed to rationalize selectivity trends. The review also illustrates how these methodologies have enabled concise syntheses of biologically relevant molecules and hedonic compounds, underscoring the growing maturity and synthetic relevance of asymmetric gold catalysis.