Transition‐Metal‐Free Approaches to Arylsulfones using Benzylic Ammonium Salts through C−N Bond Cleavage

Abstract

A transition‐metal‐free approach to benzyl sulfones by using sodium sulfinates and benzyl ammonium salts is described. The protocol provides a simple and direct method to realize the C−N bond cleavage in the presence of readily available Cs2CO3. During the reaction process, a range of functional groups with respect to both sodium sulfinates and benzylic ammonium salts were well compatible, leading to various benzyl sulfones in moderate to good yields.

Transition‐Metal Free C(sp3)−H Sulfonylation for the Synthesis of 2‐Sulfolmethyl Quinolines from 2‐Methylquinolines and Sulfonyl Hydrazides

“…Based on our research interest in sulfonyl-containing compounds, [42,[47][48][49][50][51][52][53][54][55] we used 2-methylquinoline (1 a) and benzenesulfonohydrazide (2 a) as template reaction substrates (Table 1). We first optimized the effect of solvents on the template reaction.…”

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

“…Very recently, Cs 2 CO 3 promoted the direct sulfonylation of benzylic ammonium salts with sodium sulfinates in DMF at 130 °C as presented by Tu and co-workers ( Scheme 259 ). 367 A wide variety of benzylic ammonium iodides were smoothly coupled with various aryl and heteroaryl sulfinates, leading to structurally varied benzyl sulfones in moderate to good yields. Disappointingly, sodium methanesulfinate did not afford the targeted product under the same conditions.…”

Copper-assisted preparation of pyridinyl sulfonate esters from hydroxypyridines and sodium sulfinates

“…[7][8][9][10][11] Traditional methods for the synthesis of sulfonate esters have usually focused on the esterication reaction of phenols or alcohols with sulfonyl chlorides, which requires the preparation of unstable and strongly corrosive sulfonyl chlorides in a low temperature system (down to À20 C). 12,13 Over the last decade, many chemists have become interested in direct sulfonylation reactions using various sulfonylation reagents, 14,15 including sul-nic acids, 16,17 sulnates 18,19 and sulfonyl hydrazides. [20][21][22] Among them, the stable and readily available sodium sulnate seems to be more attractive because it has demonstrated exible reactivity, such as being nucleophilic, electrophilic, and a radical reagent by providing suitable reaction conditions.…”