We have developed a diastereoselective DMAP-catalyzed Michael addition of furanone (butenolide) to nitroalkenes. Notably, our method does not require the pre-activation of furanone as 2-(trimethylsiloxy)furan and utilizes water: ethanol as a solvent. The Michael addition products were obtained in up to 82% yield and 87:13 dr. Further, the Michael adducts were transformed into Geissman-Waiss lactone derivatives in a single step.

Abstract

Selectivity plays a major role in organic chemistry and biological applications. Herein, we present a diastereoselective DMAP-catalyzed Michael addition of furanone (butenolide) to nitroalkenes. Notably, our method does not require the pre-activation of furanone as 2-(trimethylsiloxy)furan and utilizes water: ethanol (1:3) as a solvent. These mild conditions afford the anti-Michael products in up to 82% isolated yield with up to 87:13 dr (diastereomeric ratio). The scope of this reaction extends to various aromatic, heteroaromatic, and aliphatic nitroalkenes. Furthermore, we demonstrate this process on a gram scale and highlight the utility of the obtained Michael adducts for accessing natural product cores.