Copper-Mediated Synthesis of Substituted 2-Aryl-N-benzylbenzimidazoles and 2-Arylbenzoxazoles via C–H Functionalization/C–N/C–O Bond Formation
摘要:
An efficient method for the transformation of N-benzyl bisarylhydrazones and bisaryloxime ethers to functionalized 2-aryl-N-benzylbenzimidazoles and 2-arylbenzoxazoles is described. The protocol involves a copper(II)-mediated cascade C-H functionalization/C-N/C-O bond formation under neutral conditions. Substrates having either electron-donating or -withdrawing substituents undergo the cyclization to afford the target heterocycles at moderate temperature.
Nickel catalyzed sustainable synthesis of benzazoles and purines <i>via</i> acceptorless dehydrogenative coupling and borrowing hydrogen approach
作者:Gargi Chakraborty、Rakesh Mondal、Amit Kumar Guin、Nanda D. Paul
DOI:10.1039/d1ob01154e
日期:——
benzoxazole via acceptorless dehydrogenative functionalization of alcohols. Using a bench stable, easy to prepare, and inexpensive Ni(II)-catalyst, [Ni(MeTAA)] (1a), featuring a tetraaza macrocyclic ligand (tetramethyltetraaza[14]annulene (MeTAA)), a wide variety of polysubstituted benzimidazole, purine, benzothiazole, and benzoxazole derivatives were prepared via dehydrogenative coupling of alcohols with
Nitroarenes as versatile building blocks for the synthesis of unsymmetrical urea derivatives and N-Arylmethyl-2-substituted benzimidazoles
作者:Paula A. Rodríguez-Huerto、Diana Peña-Solórzano、Cristian Ochoa-Puentes
DOI:10.1007/s11696-021-01785-7
日期:2021.12
contribution, a fast and simple method for the synthesis of unsymmetrical urea derivatives and N-arylmethyl-2-substituted benzimidazoles was developed starting from nitroarenes. The reaction of nitroarenes and phenyl isocyanate or phenyl isothiocyanate in tin (II) chloride dihydrate/choline chloride eutectic mixture afforded the expected urea and thiourea derivatives, while the reaction of different aldehydes
Palladium-Catalyzed Synthesis of Benzimidazoles and Quinazolinones from Common Precursors
作者:Jessie E. R. Sadig、Radleigh Foster、Florian Wakenhut、Michael C. Willis
DOI:10.1021/jo301805d
日期:2012.11.2
utilized as complementary precursors for the synthesis of important heterocycles. The synthesis of N-substituted benzimidazoles was possible from the palladium-catalyzed reaction of both classes of substrate with a variety of N-nucleophiles. The use of the imidate precursor for the synthesis of N-substituted quinazolinones by incorporation of a palladium-catalyzed aminocarbonylation reaction has also been
A one-pot synthesis of bisarylhydrazones by Cu(I)-catalyzed aerobic oxidation
作者:Jiu-Rong Hu、Wan-Jia Zhang、Da-Gui Zheng
DOI:10.1016/j.tet.2013.08.073
日期:2013.11
An efficient Cu(I)-catalyzed one-pot synthesis of N-substituted (or NH) bisarylhydrazones is reported. A further cyclization reaction could occur towards the synthesis of benzimidazoles or triazoles with elevated temperature. A plausible alkylation-oxidation-alkylation mechanism is proposed based on experimental results and literature. (C) 2013 Elsevier Ltd. All rights reserved.