Reactivity of mixed organozinc and mixed organocopper reagents. Part 4: A kinetic study of group transfer selectivity in C-C coupling of mixed diorganocuprates

Erdik E., Özkan D.

Journal of Physical Organic Chemistry, vol.22, no.12, pp.1148-1154, 2009 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 22 Issue: 12
  • Publication Date: 2009
  • Doi Number: 10.1002/poc.1567
  • Journal Name: Journal of Physical Organic Chemistry
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1148-1154
  • Keywords: Alkylation of mixed cuprates, Competitive kinetics, Mixed magnesium cuprates, Taft plots
  • Ankara University Affiliated: Yes

Abstract

The competitive rate data and Taft relationships for the coupling of bromomagnesium n-butyl (substituted phenyl) cuprates with alkyl bromides show that selective n-butyl transfer can be explained by an oxidative addition mechanism. Taft reaction constants also show that the residual group FG-C 6H4 in the mixed cuprate n-Bu(FG-C6H 4)CuMgBr changes the ability of the copper nucleophile to react with the electrophile RBr. These results provide support for the commonly accepted hypothesis regarding the dependence of the R1 group transfer ability on the strength of R2-Cu bond in reactions of R1R 2CuMgBr reagents. Copyright © 2009 John Wiley & Sons, Ltd.