A Cross-coupling Reaction between Aliphatic Aldehydes and Sulfonium Salts

The synthesis of multi-substituted electron-deficient alkenes is often accomplished via cross-coupling of diazo compounds in the presence of a metal catalyst. Herein, we report an organocatalytic protocol that enables the direct coupling of aliphatic aldehydes with sulfonium ylides. A key carbene mimetic, alpha-iodoenamine/enol, is believed to engage in direct cross-coupling with a sulfonium ylide, delivering alpha,beta-unsaturated carbonyl compounds with a formyl substituent. The reaction demonstrated remarkably mild conditions, convergence, and control of olefin geometry.

Automated summary

An organocatalytic protocol has been developed for the direct coupling of aliphatic aldehydes with sulfonium ylides, resulting in the formation of alpha,beta-unsaturated carbonyl compounds with a formyl substituent. The reaction demonstrates mild conditions, convergence, and control of olefin geometry.