| Abstract
| - A novel regio- and stereoselective [Rh(CO)2Cl]2-catalyzed allylic alkylation of unsymmetrical allyliccarbonates was discovered. The regioselectivity of the reaction favors product ratios in which substitutionoccurs at the carbon bearing the leaving group. When an enantiomerically enriched carbonate (≥99%ee) was examined, the Rh(I)-catalyzed allylic alkylation proceeded stereoselectively to provide thealkylation product with retention of absolute stereochemistry (98% ee). To establish the scope of the[Rh(CO)2Cl]2-catalyzed allylic alkylation, a variety of carbon and heteroatom nucleophiles were examinedand the results described. As an application of the Rh(I)-catalyzed allylic alkylation, a series of noveldomino reactions have been developed that couple the unique regio- and stereoselective [Rh(CO)2Cl]2-catalyzed alkylation of allylic trifluoroacetates with an intramolecular Pauson−Khand annulation, acycloisomerization, or a [5+2] cycloaddition. A unique aspect of the method described is the use of asingle catalyst to effect sequential transformations in which the catalytic activity is moderated simply bycontrolling the reaction temperature. Implementation of such processes provides a rapid and efficiententry to a variety of bicyclic carbon skeletons from simple precursors.
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