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Diastereoselective intermolecular Pauson-Khand reactions of chiral cyclopropenes
Mahesh K Pallerla1, Joseph M Fox
1Brown Laboratories, Department of Chemistry and Biochemistry, University of Delaware, Newark, DE 19716, USA.
Abstract:
In this Letter, it is demonstrated that the unusual reactivity of cyclopropenes can increase the scope and utility of intermolecular Pauson-Khand reactions. The well-defined chiral environment of cyclopropenes has a powerful influence on the diastereoselectivity of the reactions and leads to the production of a single cyclopentenone in each of the described cases. The cyclopropane ring strongly influences the stereochemistry of reactions at the enone, and the three-membered ring can subsequently be cleaved under mild conditions. [reaction: see text]
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