Copper-Catalyzed Aerobic Decarboxylative Sulfonylation of Cinnamic Acids with Sodium Sulfinates: Stereospecific Synthesis of (E)-Alkenyl Sulfones

Abstract

A copper-catalyzed aerobic decarboxylative sulfonylation of alkenyl carboxylic acids with sodium sulfinates is developed. This study offers a new and expedient strategy for stereoselective synthesis of (E)-alkenyl sulfones that are widely present in biologically active natural products and therapeutic agents. Moreover, the transformation is proposed to proceed via a radical process and exhibits a broad substrate scope and good functional group tolerance.

Decarboxylative functionalization of cinnamic acids

“…However, cinnamic acids with substituent ortho to the -OH group inhibit this cascade process. Using a different reaction condition using catalytic CuO and sulfinate under aerobic condition (Scheme 52), Guo et al 66 successfully added the sulfonyl cation to cupric cinnamate and provided a benzyl cation 45 (Scheme 53). The benzyl cation can be trapped by I - (46) and subsequently eliminated via decarboxylation process.…”

Regioselective, One‐Pot, Three‐Component Synthesis of 1,3,4‐ and 1,3,5‐Triarylpyrazoles from 1‐ and 2‐Aryl‐1‐alkenyl Sulfones

“…Alkenyl sulfone 7a [43] was prepared in an excellent yield from 4-tolualdehyde (5) following the reported procedure [44] (Scheme 2). Another alkenyl sulfone, 10a, [45] was prepared by the nucleophilic substitution of 4-methylbenzyl chloride (8) with phenylsulfinate anion, followed by exo-methylene formation.…”

Recent advances in the synthesis of vinyl sulfones

“…Two possible reaction mechanisms for this coupling were also proposed (Scheme 29). In 2014, Guo and co-workers 53 aerobic decarboxylative sulfonylation of alkenyl carboxylic acids utilizing sodium sulfinates as the sulfur source without any silver additives for stereoselective synthesis of (E)-alkenyl sulfones. The mechanistic study indicates that the initial sulfonyl cation addition and the following decarboxylation processes are involved in this transformation (Scheme 30).…”