Photocatalytic Desulfonylative Homocoupling of Benzylic Sulfone Derivatives

Abstract

A desulfonylative homocoupling of benzylic sulfone derivatives through a photoredox Ir catalyst is described. The 3,5-bis(trifluoromethyl)phenyl group is an effective substituent on sulfonyl group in this reaction, providing the structurally diverse multiply-arylated ethanes in good yields. The -deuterated or fluorinated sulfones, which can be readily prepared by -functionalization, were also applicable, highlighting an avenue to synthesize medicinally important structures.

Visible-Light-Induced Reductive Coupling of Arylacetylenes with Benzothiazole Sulfones

“…More recently, reactions using carbon radicals generated from sulfones under visible-light irradiation have garnered considerable attention. Fluoroalkyl, β-keto, benzyl, and alkyl derivatives have emerged as radical sources in photoredox catalysis. In this context, we have been interested in developing visible-light-induced desulfonylative carbon–carbon bond formation and have reported transition-metal- and photocatalyst-free Giese-type reaction .…”

Homocoupling of benzyl pyridyl ethers via visible light-mediated deoxygenation

“…20 More recently, visible-light photoredox catalysis has emerged as a mild and effective alternative for bibenzyl synthesis through photoinduced reductive cleavage (Scheme 2b). [21][22][23] However, the reaction scope is currently limited to benzyl halides, with the exception of a recent report on benzylic sulfone, 24 and concerns remain around toxicity and instability of the reaction substrates.…”