Temporary silicon tethered rhodium(I)-catalyzed intramolecular [4+2+2] cycloadditions: Studies toward the total synthesis of (+)-epoxydictymene

ORGN 13

P. Andrew Evans and Erich W. Baum. Department of Chemistry, Indiana University, 800 E. Kirkwood, Bloomington, IN 47405

Transition metal-catalyzed carbocyclizations provide an expeditious entry into complex fused polycyclic frameworks. We have developed a new intramolecular diastereoselective temporary silicon tethered rhodium(I)-catalyzed [4+2+2] cycloaddition for the synthesis of 5-8 fused carbocycles. The key advantage of this approach is the ability to significantly increase molecular complexity in a stereocontrolled fashion using a single transformation. The reaction’s scope, limitations and application towards the synthesis of the 5-8-5-5 diterpene (+)-epoxydictymene will be presented.

New Reactions and Methodology 8:00 AM-12:00 PM, Sunday, March 28, 2004 Anaheim Convention Center -- 303A, Oral Division of Organic Chemistry The 227th ACS National Meeting, Anaheim, CA, March 28-April 1, 2004