An Effective Synthesis of α-Cyanoenamines by Peterson Olefination

Abstract

A convenient and gentle method for the synthesis of α-cyanoenamines based on the Peterson olefination has been developed. For these sensitive, highly functionalized olefins, the present method is superior to the Horner-Emmons condensation, as manifested by the higher yields and broader scope.

Key words

α-Cyanoenamines - Peterson olefination - Horner-Emmons condensation

References

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5

In our preliminary attempts on the Peterson olefination, we have employed n-BuLi and LDA for the reaction with the aldehyde 2a, but obtained poor yields of the desired α cyanoenamine 3a, e.g., none with n-BuLi and only a 7% yield in the case of LDA.