Diastereoselective Synthesis of Cyclopenta[ c ]chromanones via Pd 0 -Catalyzed [3+2] Cycloaddition.

A straightforward method for synthesizing cyclopenta[ c ]chromanones is demonstrated. The strategy involves a [3+2] cycloaddition of VCPs and activated coumarins under Pd-catalyzed conditions. The reaction provides the desired products bearing up to four consecutive stereocenters with high diastereocontrol. Control experiments and density functional theory studies support the proposed mechanism and the observed diastereoselectivity in the product through a thermodynamically controlled pathway.