New metal-catalyzed carbocyclization reactions for the construction of complex natural products

Abstract

The chemo- and stereoselective aspects of the rhodium-catalyzed [m+n+o] carbocyclization reactions of carbon and heteroatom tethered 1,6-enynes with dienes and alkynes are described. The inter- and intramolecular rhodium-catalyzed [4+2+2] carbocyclization reactions provide a convenient and highly diastereoselective approach to bicyclooctanoids, in which the intramolecular version utilizing a temporary silicon-tether circumvents the issues of poor selectivity and reactivity with substituted dienes. The crossed intermolecular rhodium-catalyzed [2+2+2] carbocyclization reaction provides a convenient approach to bicyclohexadienes, in which the regio- and enantioselective variant addresses the challenges with the regiochemical incorporation of unsymmetrical alkynes. © ARKAT.