Electrophilic amination of Cu(I) catalyzed phenylmagnesium bromide with N,O-bis(trimethylsilyl) hydroxylamine in THF:N-donor solvent. Control of C-N and C-O chemoselectivity

KAHYA N. D., EROĞLU F.

JOURNAL OF ORGANOMETALLIC CHEMISTRY, vol.899, 2019 (SCI-Expanded, Scopus) identifier

  • Publication Type: Article / Article
  • Volume: 899
  • Publication Date: 2019
  • Doi Number: 10.1016/j.jorganchem.2019.120884
  • Journal Name: JOURNAL OF ORGANOMETALLIC CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: Electrophilic amination, N, O-bis(trimethylsilyl)hydroxylamine, Aryl Grignard reagents, Arylamines, Atom-economy, C-N coupling, GRIGNARD-REAGENTS, ORGANOCUPRATE CLUSTERS, ORGANOZINC REAGENTS, ALPHA-AMINATION, ALKYL-HALIDES, COPPER, AMINES, MECHANISM, MAGNESIUM, ARYL
  • Ankara University Affiliated: Yes

Abstract

Reaction of PhMgBr with (Me3Si) HNO(SiMe3)[TMSHA] in the presence of CuI or CuCN catalysis (10-20 mol %) in THF:cosolvent (cosolvent = HMPA or TMEDA) at room temperature can provide an atom-economic and step-economic access for arylamine synthesis starting from aryl Grignard reagents. Chemoselectivity to yield C-N or C-O coupling can be controlled by changing reaction parameters. Cu(I) catalyzed reaction of PhMgBr in THF or in THF:HMPA (or TMEDA) affords both C-N and C-O coupling products, i.e. aniline and phenol (mol ratio >= 7:3), whereas uncatalyzed reaction of PhMgBr gives phenol. Mechanisms were proposed for the solvent dependence of chemoselectivity in the coupling of both uncatalyzed and Cu(I) catalyzed Grignard reagent with (TMS)HNO(TMS). (C) 2019 Elsevier B.V. All rights reserved.