Rhodium(I)-catalyzed [2+2+1] cycloadditions of 1,3-dienes, alkenes, and CO

J Am Chem Soc. 2004 May 19;126(19):5948-9. doi: 10.1021/ja0489487.

Abstract

Initial examples of a Rh(I)-catalyzed [2+2+1] reaction of diene-enes and CO are described. This method allows for the facile, efficient, and diastereoselective construction of a variety of alkenyl cyclopentanones in good to excellent yields. Control studies show that the diene moiety is required for this process as bis-enes do not give the [2+2+1] products under the same conditions.