Synthesis of Symmetrical Sulfides Enabled by a Sulfur Dioxide Surrogate Acting as a Divalent Sulfur Source

One-Pot Stepwise Dechalcogenization of Trisulfides to Unsymmetrical Dialkyl Thioethers

The construction of C-S bonds has garnered significant interest due to the ubiquitous presence of organosulfur compounds in natural products and bioactive molecules. Herein, we report a one-pot, stepwise desulfuration strategy employing trisulfides as precursors for the synthesis of unsymmetrical dialkylthioethers. Our study demonstrates that copper powder facilitates the conversion of trisulfides into disulfides, which subsequently undergo a nickel-catalyzed reductive coupling to afford the desired products. This approach provides a practical, odorless, and broadly applicable method for the synthesis of unsymmetrical dialkylthioethers.

Iodine/DMF-Mediated Regioselective Sulfenylation Using Arenediazonium Tosylates and Sodium Metabisulfite: An Easy Access to 3-Arylthioindoles

A practical C3 sulfenylation of indoles has been accomplished using arenediazonium tosylates and sodium metabisulfite, with a key role of iodine/DMF combination in the reaction. The method involves scarce use of sodium metabisulfite as a divalent sulfur source and offers an array of structurally diverse 3-arylthioindoles in high yields under operationally simple transition-metal-free and mild conditions.

Synthesis of β,β-Dithioketones by Merging C-C and C-S Bond Cleavage in [1 + 1 + 1 + 1 + 1 + 1] Annulation

An unconventional [1 + 1 + 1 + 1 + 1 + 1] annulation process was developed for the construction of β,β-dithioketones by merging C-C and C-S bond cleavage. In this reaction, rongalite concurrently served as triple C1 units, dual sulfur(II) synthons, and a reductant for the first time. Mechanism investigation indicated that the reaction involved the self-mediated valence state change of rongalite. By performing this step-economical method, the challenging construction of C5-substituted 1,3-dithiane can be achieved under mild and simple conditions.

Pyrosulfite-Involved Synthesis of Sulfides by Palladium-Catalyzed Decarboxylative Couplings

The decarboxylative coupling using carboxylic acid and potassium metabisulfite, promoted by a palladium catalyst, is reported for the generation of sulfides. The coupling is performed using the easily available carboxylic acid and environmentally friendly inorganic sulfides as a divalent inorganic sulfur source. Not only aromatic acids but also aliphatic carboxylic acids are workable during the couplings. The method is applicable and practical to a scope of 20 examples and drug molecules.

One-pot synthesis of 11-sulfenyl dibenzodiazepines via tandem sulfenylation/cyclization of o-isocyanodiaryl amines and diaryl disulfides

A one-pot sulfenylation/cyclization of o-isocyanodiaryl amines has been described for the preparation of 11-sulfenyl dibenzodiazepines. This AgI-catalyzed reaction covers an unexplored tandem process to give seven-membered N-heterocycles. This transformation shows a broad range of substrate scope, simple operation, and moderate to good yields under aerobic conditions. Diphenyl diselenide can also be produced in an acceptable yield.