Reciprocal-Activation Strategy for Allylic Sulfination with Unactivated Allylic Alcohols.

A reciprocal-activation strategy for allylic sulfination with unactivated allylic alcohols was developed. In this reaction, the hydrogen bond interaction between allylic alcohols and sulfinic acids allowed for reciprocal activation, which enabled a dehydrative cross-coupling process to occur under mild reaction conditions. This reaction worked in an environmentally friendly manner, yielding water as the only byproduct. A variety of allylic sulfones could be obtained in good to excellent yields with wide functional group tolerance. In gram scale reactions, allylic sulfones could be conveniently isolated in high yield by filtration.