Copper-Catalyzed Tandem Sulfuration/Annulation of Propargylamines with Sulfur via C–N Bond Cleavage

Abstract

Copper-catalyzed aerobic oxidative sulfuration and annulation of propargylamines with elemental sulfur is described. The tandem reaction involves C–N bond cleavage and the formation of multiple C–S bonds, affording 1,2-dithiole-3-thiones in good to excellent yields with good functional group tolerance.

Recent Advances in the Synthesis of Heterocycles via Reactions Involving Elemental Sulfur

“…Reported recent syntheses were based on the use of elemental sulfur as both three-sulfur atom donor and redox reagent on different derivatives of 1arylpropynes 127 such as trifluoromethyl 127 a [53] (Scheme 47, entry 1) or propargylamines 127 b (Scheme 47, entry 2). [54] In both cases, the reactions were performed in the presence of copper(I) salts as catalyst at 120°C. Sulfides issued from disproportionation reaction of elemental sulfur in the presence of inorganic bases such as Cs 2 CO 3 and K 3 PO 4 , were suggested to initiate the reaction in these two cases.…”

Chan–Lam-Type C–S Coupling Reaction by Sodium Aryl Sulfinates and Organoboron Compounds

“…However, the large-scale utilization of thiols is often complicated by their repulsive odor and the associated toxicity. To circumvent this problem, different sulfur surrogates, such as sulfonyl chloride, Bunte salt, S 8 , and xanthate, were used as alternatives to thiols for thioether preparation. Despite the effectiveness of using these sulfur surrogates, the use of reactive reagents, the need for specialized reaction conditions, or the multiple synthetic steps used often limits their application.…”

Copper‐Catalyzed Electrophilic Cyclization of N‐Propargylamines with Sodium Sulfinate for the Synthesis of 3‐Sulfonated Quinolines

“…The model reaction of N‐( 3‐phenylprop‐2‐yn‐1‐yl)aniline 1 a with sodium benzenesulfinate 2 a under air atmosphere was chosen to optimize the reaction conditions, and the results can be seen in Table . Treatment of propargylamine 1 a and 2 a with 10 mol % catalyst CuI, 2 equiv.…”