Preparation of 1,2-substituted benzimidazoles via a copper-catalyzed three component coupling reaction

Abstract

The intermediate N-sulfonylketenimine occurred with two nucleophilic addition, and the sulfonyl group was easily eliminated through cyclization.

Facile access to 1,2-disubstituted benzimidazoles and 2,3-dihydro-1H-perimidines using a biogenically synthesized single phase δ-MnO2 NP catalyst and its dye removal study

“…7 Under these circumstances, metal-catalyzed dehydrogenative coupling of biomass driven alcohols with 1,2-diaminobenzene and 1,8-diaminonaphthalene is emerging as an unconventional synthetic approach for disubstituted benzimidazole and perimidine synthesis respectively releasing water and the hydrogen gas as the only non-toxic side products. 8 However, these strategies are often limited to noble-metal based catalysts and operate mostly under homogeneous reaction conditions. 9 In typical Hydrogen Auto-transfer (HA)/Acceptorless Dehydrogenative Coupling (ADC) reactions, metal catalysts such as Mn, Fe, Ni, Co, and Cu are well explored for homogeneous catalysis.…”

Synthesis of 1-Benzyl-2,4-diarylimidazole through I2/CuI-Catalyzed Cyclization of Benzylamine and Hydrazone

“…In 2021, Yang's group 23 eliminated by the power of cyclization. The reaction is fast and efficient, with a good substrate compatibility, but because the raw material contains azides, the reaction presents a certain risk.…”

“…In 2021, Yang’s group established a new and effective three-component reaction for the synthesis of 1,2-substituted benzimidazole (Scheme b), during which sulfonyl azide and a copper catalyst activate the terminal alkyne to form an intermediate, the intermediate N -sulfonyl imide is cyclized after two nucleophilic reactions, and the sulfonyl group is eliminated by the power of cyclization. The reaction is fast and efficient, with a good substrate compatibility, but because the raw material contains azides, the reaction presents a certain risk.…”

Design, step-economical diversity-oriented synthesis of an N-heterocyclic library containing a pyrimidine moiety: discovery of novel potential herbicidal agents

“…In addition to pyrimidine, other N-heterocycles have also received considerable attention because of their medicinal and agrochemical importance, 15 including pyrazole, benzimidazole, indole, tetrahydrocarbazole, etc. ( Fig.…”