Asymmetric Formal [3+2] Cycloaddition Reaction of Succinaldehyde and Nitroalkene Catalyzed by Diphenylprolinol Silyl Ether

The enantioselective domino Michael/Henry reaction of nitroalkenes with succinaldehyde was found to proceed efficiently upon using diphenylprolinol silyl ether as the organocatalyst. The reaction affords cis-disubstituted nitropentenes with excellent diastereoselectivities and enantioselectivities after treatment of the Michael product with Ac₂O and pyridine. cis-Disubstituted nitropentenes are obtained with excellent diastereoselectivities and enantioselectivities by a formal [3+2] cycloaddition reaction. The first reaction is a domino reaction composed of the diphenylprolinol silyl ether mediated Michael reaction of nitroalkene with succinaldehyde followed by a Henry reaction. The next reaction is a dehydration achieved by using Ac₂O and pyridine.