Iodine/Manganese Dual Catalysis for Oxidative Dehydrogenation Coupling of Amines with Thiols

Synthesis of Sulfenamides via Photoredox N-S Coupling of Dialkyl Azodicarboxylates and Thiols

We herein report a photoredox N-S coupling reaction between dialkyl azodicarboxylates and thiols to access sulfenamide scaffolds. This reaction proceeds under mild, green, and operationally simple conditions, offering a broad scope of sulfenamides with high yields and excellent atom efficiency. Mechanistic investigations revealed this reaction followed a photoinitiated radical pathway in which iodide plays a crucial role as both a radical initiator and a single-electron reductant.

Selective Synthesis of Sulfonamides and Sulfenamides from Sodium Sulfinates and Amines

An effective method was explored for the selective synthesis of sulfonamides and sulfenamides using sodium sulfinates and amines as starting materials. This method offers mild reaction conditions, a broad substrate scope, high efficiency, and readily accessible materials, making it suitable and an alternative strategy for the preparation of a variety of biologically or pharmaceutically active compounds.

Thiosuccinimide enabled S-N bond formation to access N-sulfenylated sulfonamide derivatives with synthetic diversity

A thiosuccinimide enabled S-N cross-coupling strategy has been established for the intermolecular N-sulfenylation of clinically approved sulfa drugs under additive-free conditions. This approach features simple operation, high chemoselectivity for sulfenylating the phenylamino group of sulfonamides, wide substrate scope, and easy scale production, affording N-sulfenylated products in moderate to excellent yields (up to 90%). In addition, we also found that this transformation can be realized in a one-pot manner by employing readily available thiols as starting materials, and the obtained sulfonamide derivatives are capable of various late-stage functionalizations, including oxidation, arylation, benzylation, and methylation.

Chemodivergent Synthesis of Benzothiadiazin-3-one 1-Oxides and Benzisothiazol-3-ones via Visible Light-Promoted Intramolecular N-S Bond Formation

We reported a versatile protocol to chemodivergently construct significant heterocyclic scaffolds of benzothiadiazin-3-one 1-oxides and benzisothiazol-3-ones by visible light-promoted photocatalysis. This substrate-dependent chemoselective strategy enables N-(2-mercaptophenyl)-N'-substituted ureas through the N-S bond coupling/oxidation cascade to selectively produce benzothiadiazin-3-one 1-oxides; however, the transformation of 2-mercaptobenzamides only occurs via N-S bond coupling to access benzisothiazol-3-ones with moderate to good yields. This strategy features mild conditions, excellent chemoselectivity, and functional group compatibility, which has potential applications in organic and medicinal chemistry.

Sustainable aerobic oxidative coupling of thiols and amines for selective formation of sulfenamides using MOF-derived cobalt nanoparticles supported on N-doped carbon

A heterogeneous catalyst system has been developed for the aerobic oxidative coupling of thiols with amines for the selective formation of various sulfenamides with ZIF-67-derived cobalt-based N-doped carbon catalysts.

Oxidative cross-coupling of thiols for S-X (X = S, N, O, P, and C) bond formation: mechanistic aspects

This review focuses on the reactive intermediates (disulfides, sulfenyl halides, thiyl radicals, sulfenium cations, and metal-organosulfur species) and the mechanisms of the recently reported oxidative couplings of thiols. These intermediates are generated by chemical oxidants, transition metal catalysts, electrochemistry, and photochemistry. Chemical oxidant-mediated reactions involve radical, halogenated, or cationic intermediates, or disulfides. Transition metal-catalyzed mechanisms proposed various metal-organosulfur intermediates to elucidate the reactivity and selectivity of metal catalysts. In electro- and photooxidation, direct oxidation/reduction mechanisms of reactants at the electrode or indirect oxidation/reduction of reactants in the presence of redox catalysts have been reported. The following sections are based on the products, thiosulfonates (S-S bond), sulfenamides, sulfinamides, and sulfonamides (S-N bond), sulfinates (S-O bond), thiophosphine oxides and thiophosphates (S-P bond), and sulfides, sulfoxides, and sulfones (S-C bond) and discuss the reaction mechanisms and the above-mentioned key intermediates for product formation. The contents of this review will provide helpful information, guiding the choice of oxidative coupling conditions for the synthesis of various organosulfur compounds with high yields and selectivity.

Direct synthesis of sulfenamides, sulfinamides, and sulfonamides from thiols and amines

Needless to say that organosulfur compounds with sulfur–nitrogen bonds have found various applications in diverse fields such as pharmaceuticals, agrochemicals, polymers, and so forth. Three major groups of such compounds are sulfenamides, sulfinamides, and sulfonamides which have been widely applied as building blocks in medical chemistry. Owing to their significant role in drug design and discovery programs, the search for and development of efficient, environmentally friendly, and economic processes for the preparation of the title compounds is of great importance in the pharmaceutical industry. Recently, oxidative coupling of thiols and amines, two readily available low-cost commodity chemicals, has emerged as a highly useful method for synthesizing structurally diverse sulfenamides, sulfinamides, and sulfonamides in a single step. Since this strategy does not require additional pre-functionalization and de-functionalization steps, it considerably streamlines synthetic routes and substantially reduces waste generation. This review will focus on recent advances and achievements in this attractive research arena.

This review provides a concise overview of the synthesis of biologically and synthetically valuable sulfenamide, sulfinamide, and sulfonamide derivatives through the direct oxidative coupling of readily available low-cost thiols and amines.

Selective oxidative intermolecular carbosulphenylation of aryl alkenes with thiols and nucleophiles via a 1,2-dithioethane intermediate

A periodate lithium-oxidized difunctionalisation of aryl alkenes with thiols and electron-rich aromatics was achieved, selectively affording more than thirty carbosulphenylated products. Both experiments and quantum chemical calculations demonstrated the radical-polar nature of the processes, and that 1,2-dithioethane and thiiranium ions might play the role of intermediates.

Oxidative C–H Acyloxylation of Acetone with Carboxylic Acids under Iodine Catalysis

Iodine-catalyzed oxidative C(sp3)–H acyloxylation of acetone with carboxylic acids has been developed. The method employs iodide­ as catalyst and sodium chlorite as oxidant. Substituted benzoic acids, naphthoic acids and heteroaromatic carboxylic acids can be used, and 2-oxopropyl carboxylates are obtained with good to excellent yields.