Copper(I)-Catalyzed Synthesis of Substituted 2-Mercapto Benzimidazoles

Abstract

An efficient method for the preparation of various substituted 2-mercapto benzimidazoles from their corresponding thioureas has been developed. S-alkylation of thioureas followed by Cu-catalyzed intramolecular N-arylation furnished substituted 2-mercapto benzimidazoles in high yields and short reaction times. Furthermore, 2-mercapto benzimidazoles substituted with a p-methoxybenzyl group allowed access to benzimidazole thiones.

Copper(I)‐Catalyzed Cascade Synthesis of 2‐Arylsulfanyl‐ arylcyanamides

“…[1h] As a part of our ongoing research in developing alternative methods for the synthesis of heterocycles, [6,7] and taking cues from our recent double S-arylation strategy involving intra-and intermolecular C À S coupling, [1h] we envisaged a one-pot synthesis of N-aryl-2-aminobenzothiazoles. The retrosynthetic strategy is shown in Scheme 1.…”

Copper‐Catalyzed Direct Synthesis of 3‐Arylindoles

“…In connection with our ongoing research on Cu I -catalyzed carbon-heteroatom bond formation to access organonitrogen compounds [11] and heterocycles, [12] we have extended our methods to access valuable 3-arylindoles. By taking cues from our previous report on Cu-catalyzed allylic aminations with nitrosoarenes (Scheme 1) in which formation of N-allylhydroxylamine followed by deoxygenation occurs to give N-allylamine, [13] we envisaged that the formation of N-hydroxyindole followed by deoxygenation could lead to 3-arylindoles (Scheme 2).…”

Isocoumarins: General Aspects and Recent Advances in their Synthesis

“…The advantage of this catalyst system is that it is economically cheap and has good functional tolerance. There are several Cu‐catalyzed reactions reported for the efficient construction of heterocycles such as indoles, benzofurans, quinolines, isoqunolines, quinazalines, quinazolones, isoflavones, etc. via addition/cyclization or coupling/cyclization reactions.…”