Synthesis of Vinylsulfones Via Palladium-Catalyzed Decarboxylative Coupling of Cinnamic Acids with Aromatic Sulfinic Acid Sodium Salts

Organic Sulfinic Acids and Salts in Visible Light-Induced Reactions

Sulfinic acids and their salts are a useful source of sulfur-containing structures. Photocatalysis of these compounds with visible light enables to achieve various transformations under mild conditions. This review summarizes visible-light-induced reactions of sulfinic acids and their salts. It is organized by reaction type and brief discussions on plausible reaction mechanisms for typical transformations are presented.

1 Introduction

2 Sulfonylation Reactions

2.1 Sulfonylation of Alkenes

2.2 Sulfonylation of Alkynes

2.3 Sulfonylation of Arenes

2.4 sp3 C–H Functionalization

3 Desulfonylation Reactions

4 Sulfenylation Reactions

4.1 Sulfenylation of Heteroarenes

4.2 Sulfenylation of Carbonyl Chlorides

5 Conclusions

Synthesis and applications of sodium sulfinates (RSO2Na): a powerful building block for the synthesis of organosulfur compounds

This review highlights the preparation of sodium sulfinates (RSO2Na) and their multifaceted synthetic applications. Substantial progress has been made over the last decade in the utilization of sodium sulfinates emerging as sulfonylating, sulfenylating or sulfinylating reagents, depending on reaction conditions. Sodium sulfinates act as versatile building blocks for preparing many valuable organosulfur compounds through S-S, N-S, and C-S bond-forming reactions. Remarkable advancement has been made in synthesizing thiosulfonates, sulfonamides, sulfides, and sulfones, including vinyl sulfones, allyl sulfones, and β-keto sulfones. The significant achievement of developing sulfonyl radical-triggered ring-closing sulfonylation and multicomponent reactions is also thoroughly discussed. Of note, the most promising site-selective C-H sulfonylation, photoredox catalytic transformations and electrochemical synthesis of sodium sulfinates are also demonstrated. Holistically, this review provides a unique and comprehensive overview of sodium sulfinates, which summarizes 355 core references up to March 2020. The chemistry of sodium sulfinate salts is divided into several sections based on the classes of sulfur-containing compounds with some critical mechanistic insights that are also disclosed.

Silver-promoted synthesis of vinyl sulfones from vinyl bromides and sulfonyl hydrazides in water

The synthesis of vinyl sulfones via silver-promoted cross-coupling of vinyl bromides with sulfonyl hydrazides was realized. Water was used as the sole solvent. Multisubstituted vinyl sulfones were easily prepared with excellent alkyl group tolerance. A mechanism involving nucleophilic attack of a sulfinate anion was proposed.

Visible-light-induced decarboxylative sulfonylation of cinnamic acids with sodium sulfinates by using Merrifield resin supported Rose Bengal as a catalyst

A visible-light-induced decarboxylative sulfonylation of cinnamic acids with sodium sulfinates for the synthesis of vinyl sulfones was developed. The reaction proceeded smoothly in the presence of Merrifield resin supported Rose Bengal ammonium salt as a photocatalyst and tert-butyl hydroperoxide (70% in water) as an oxidant in aqueous DMSO solution at room temperature under green LED (530-535 nm) irradiation under an air atmosphere, generating the desired products in good yields. Notably, the supported catalyst can easily be separated from the reaction mixture by filtration and can be recycled at least six times without any significant loss of activity.

E-Selective synthesis of vinyl sulfones via silver-catalyzed sulfonylation of styrenes

An efficient and highly E-selective protocol for the synthesis of vinyl sulfones is described. This simple protocol demonstrates the first synthesis of vinyl sulfones via a silver-catalyzed C-S bond coupling reaction. In addition, the success of the reaction was found to be critically dependent on the use of TEMPO as the additive.

Silver-catalyzed decarboxylative C(sp2)–C(sp3) coupling reactions via a radical mechanism

A silver catalyzed decarboxylative C(sp²)–C(sp³) coupling of vinylic carboxylic acids with alcohols, alkylbenzenes, cycloalkanes and cyclic ethers was developed by using DTBP as an oxidant.

Visible-Light-Enabled Decarboxylative Sulfonylation of Cinnamic Acids with Sulfonylhydrazides under Transition-Metal-Free Conditions

Decarboxylative cross-coupling reactions of cinnamic acids with sulfonylhydrazides were explored using oxygen as the sole terminal oxidant, realizing a conceptually novel technology for vinyl sulfone synthesis under the synergistic interactions of visible light irradiation, organic dye-type photocatalyst eosin Y, KI, and Cs2CO3 at room temperature.

Mn(iii)-mediated regioselective synthesis of (E)-vinyl sulfones from sodium sulfinates and nitro-olefins

A new efficient Mn(iii)-mediated coupling reaction of sodium sulfinates with nitro-olefins is described.

Recent advances in the synthesis of vinyl sulfones

This review focus on recent achievements in vinyl sulfones synthesis and the mechanisms of the reactions are also discussed.

PhI(OAc)2 mediated decarboxylative sulfonylation of β-aryl-α,β-unsaturated carboxylic acids: a synthesis of (E)-vinyl sulfones

A highly efficient metal-free decarboxylative sulfonylation protocol for the preparation of (E)-vinyl sulfones from of β-aryl-α,β-unsaturated carboxylic acids using sodium sulfinates and (diacetoxyiodo)benzene (PhI(OAc)2) was developed. This strategy offers a simple and expedient synthesis of (E)-vinyl sulfones bearing a wide variety of functional groups. A radical-based pathway has been proposed for this decarboxylative sulfonylation reaction.

Decarboxylative functionalization of cinnamic acids

Decarboxylative functionalization of α,β-unsaturated carboxylic acids is an emerging area that has been developed significantly in recent years.

Iodine-mediated synthesis of (E)-vinyl sulfones from sodium sulfinates and cinnamic acids in aqueous medium

A green and highly efficient method for the synthesis of (E)-vinyl sulfones promoted by iodine in water has been developed, without transition metal catalysts and ligands.