Selective and Efficient Generation of ortho-Brominated para-Substituted Phenols in ACS-Grade Methanol

Molecules. 2016 Jan 13;21(1):88. doi: 10.3390/molecules21010088.

Abstract

The mono ortho-bromination of phenolic building blocks by NBS has been achieved in short reaction times (15-20 min) using ACS-grade methanol as a solvent. The reactions can be conducted on phenol, naphthol and biphenol substrates, giving yields of >86% on gram scale. Excellent selectivity for the desired mono ortho-brominated products is achieved in the presence of 10 mol % para-TsOH, and the reaction is shown to be tolerant of a range of substituents, including CH3, F, and NHBoc.

Keywords: ACS-grade methanol; NBS; ortho-bromination.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Benzenesulfonates / chemistry
  • Biphenyl Compounds / chemistry*
  • Bromosuccinimide / chemistry
  • Halogenation
  • Kinetics
  • Methanol / chemistry*
  • Naphthols / chemistry*
  • Phenol / chemistry*
  • Solvents

Substances

  • Benzenesulfonates
  • Biphenyl Compounds
  • Naphthols
  • Solvents
  • Phenol
  • Bromosuccinimide
  • 4-toluenesulfonic acid
  • Methanol