Synthesis of Symmetrical Thiosulfonates via Cu(OTf)₂‐Catalyzed Reductive Homocoupling of Arenesulfonyl Chlorides

Abstract

A variety of symmetrical thiosulfonates are synthesized via Cu‐catalyzed reductive homocoupling of aryl sulfonyl chlorides. This protocol uses organic amine acting as a mild reductant and low‐cost copper as an effective catalyst. Such a reductive coupling process features a broad substrate scope and good functional group tolerance. Related thiosulfonate products can also be converted into diverse functional molecules.

Oxidation of Thiols with IBX or DMP: One-pot Access to Thiosulfonates or 2-Iodobenzoates and Applications in Functional Group Transformations

“…2-bromobenzenesulfonothioate (2g) 30 White solid; Yield: 84 mg (78%) (with IBX) and 42 mg (79%) (with DMP); mp. 120122 °C; IR (KBr) cm -1 3085, 1570, 1445, 1327, 1149, 775, 593; 1 H NMR (CDCl3, 500 MHz) δ 7.267.30 (m, 2H), 7.33 (td, J = 7.5 Hz, J = 1.4 Hz, 1H), 7.41 (td, J = 7.6 Hz, J = 1.6 Hz, 1H), 7.53 (dd, J = 7.9 Hz, J = 1.4 Hz, 1H), 7.57 (dd, J = 7.9 Hz, J = 1.7 Hz, 1H), 7.69 (dd, J = 7.6 Hz, J = 1.7 Hz, 1H), 7.78 (dd, J = 6.4 Hz, J = 1.1 Hz, 1H); 13…”

“…20 A number of methodologies have thus far been reported to access thiosulfonates. 4,12 Four main strategies followed for their synthesis are: i) from thiols or disulfides in the presence of oxidants with [21][22][23] or without [24][25][26][27][28] involvement of transition metals, ii) the addition of disulfides or thiols to sodium sulfonate, 29 iii) the reductive coupling of sulfonyl chlorides 16,30 and sulfonyl hydrazides with or without metal catalyst, [31][32][33][34] and iv) the reaction of sulfonyl halides 35 with other thiols or thiolates. 4,12 In addition, electrochemical methods are also known for the synthesis of thiosulfonates.…”

Synthesis of 1,3-Dibenzenesulfonylpolysulfane (DBSPS) and Its Application in the Preparation of Aryl Thiosulfonates from Boronic Acids

“…Therefore, it is necessary to develop new sulfur reagents to efficiently construct carbon–sulfur bonds. As a new type of sulfur functional reagent, thiosulfonate − has attracted the attention of synthetic chemists due to its high stability and low toxicity compared with traditional sulfur reagents. − Traditional methods − for the construction of thiosulfonates were mostly based on the cross coupling reaction of sulfone substrates and disulfide or mercaptan (Figure A-a). Recently, the construction of the sulfone radical through the insertion of SO 2 and then coupling with mercaptan to construct thiosulfonate has attracted a great deal of attention − (Figure A-b).…”

Reductive Coupling of Sodium Sulfinates for the Synthesis of Thiosulfonates

“…3 Moreover, thiosulfonates have been increasingly used as synthetic intermediates in organic synthesis due to their better reactivity and stability compared with sulfenyl halides and disulfides. 4 Therefore, considerable efforts have been devoted to the synthesis of thiosulfonates. Typical approaches to symmetric thiosulfonates include oxidation of thiols or disulfides and reduction of sulfonyl chlorides or hydrazides with stoichiometric amounts of oxidants or reductants (Scheme 1a).…”

“…Only trace amounts of products were detected using DMSO as the solvent (Table 1, entry 2). Further screening of solvents revealed that other solvents such as DCE, DMF and MeCN provided similar yields with chloroform (Table 1, entries [3][4][5]. Subsequently, the hydrogen donor Hantzsch ester diethyl 2,6-dimethyl-1,4dihydropyridine-3,5-dicarboxylate (HE) was added to the reaction.…”