ChemInform Abstract: Metal‐Free Carbon—Carbon Cross‐Couplings Between the Ion Pairs in Sulfonium Tetraphenylborates.

Abstract

Abstract A series of sulfonium tetraphenylborates can be readily prepared by the metathesis of sulfonium halides with sodium tetraphenylborates. After heating at 120–150 °C, the sulfonium tetraphenylborates can smoothly undergo the cross-couplings between the tetraphenylborate anions and the sulfonium cations in the absence of a metal catalyst. For carbonylmethyl-, benzyl-, and allylsulfoniums, the corresponding carbonylmethyl–phenyl, benzyl–phenyl, and allyl–phenyl cross-coupling products can be obtained in 22–76% yields. An interionic electron-transfer mechanism for this cross-coupling reaction is proposed.