Synthesis of 3-arylindole derivatives from nitroalkane precursors

Abstract

3-Arylindole derivatives were synthesized by Cu(i) catalysed intramolecular Ullmann coupling of 2-bromoarylaminoalkanes.

Recent Progress in the Transition Metal Catalyzed Synthesis of Indoles

“…N-benzyl substituted-2-iodobenzamide is less reactive and stable in the reaction conditions and gave the worse results. Yao and co-workers prepared 3-arylindoles from 2-bromoarylaminoalkanes under Cu(I) catalysis (Scheme 19) [42]. The starting materials were obtained in the same paper by Friedel-Crafts alkylation of bromo-substituted β-nitrostyrenes and arenes.…”

“…2-Bromo-4-methoxy-1-(2-nitro-1-(2nitrophenyl)ethyl)benzene did not cyclize under copper catalysis but it furnished 3-(2-bromo-4methoxyphenyl)-1H-indole in 91% yield when refluxed with Fe (5 equiv) in AcOH/EtOH. Yao and co-workers prepared 3-arylindoles from 2-bromoarylaminoalkanes under Cu(I) catalysis (Scheme 19) [42]. The starting materials were obtained in the same paper by Friedel-Crafts alkylation of bromo-substituted β-nitrostyrenes and arenes.…”