Ag(I)-Catalyzed Michael Additions of β-Ketoesters to Nitroalkenes in Water: Remarkable Effect of Water as a Reaction Medium on Reaction Rates

Abstract

AgOTf-PPh₃ complex-catalyzed Michael additions of β-ketoesters to nitroalkenes in water were performed. The system promotes the reaction efficiently only in water, and interestingly the reaction does not proceed well in organic solvents. In addition, this ­reaction system could be applied to catalytic asymmetric synthesis in water.

water - silver - Michael additions - solvent effects - asymmetric synthesis

References and Notes

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<A NAME="RU01606ST-11">11</A>

Various Ag/(R)-Tol-BINAP ratios were tested, and the ratio in Scheme [1] gave better results.

<A NAME="RU01606ST-12">12</A>

Extraction solvents other than CH₂Cl₂ (ex. EtOAc) can also be used.