Rhodium-catalyzed [2+2+2+1] cycloaddition reaction: Application to the construction of fused 5-7-5 ring systems from various enediynes

ORGN 76

Bibia Bennacer and Iwao Ojima. Department of Chemistry, State University of New York at Stony Brook, Stony Brook, NY 11794-3400

Fused polycyclic molecules are of significant interest due to their prevalence in biologically active molecules such as phorbol, karajinone B or cyclomyrsinol. Transition metal-catalyzed carbocyclization plays an important role in organic synthesis and is a powerful tool to construct such fused systems in an efficient manner. We will report here our study on the novel Rh-catalyzed [2+2+2+1] cycloaddition reaction of enediynes and CO, affording the corresponding 5-7-5 ring systems ("CO-CaT" process). The scope of this unique process and the crucial factors for product selectivity will be discussed.

New Reactions and Methodology, Metal-Mediated Reactions, Heterocycles and Aromatics 8:00 PM-10:00 PM, Sunday, March 28, 2004 Anaheim Convention Center -- Hall A, Poster Division of Organic Chemistry The 227th ACS National Meeting, Anaheim, CA, March 28-April 1, 2004