Reactivities of mixed organozinc and mixed organocopper reagents. Part 13 Kinetic study for phosphine-catalyzed acylation of alkylarylzincs and effect of residual group on the transfer rate of alkyl group

Pekel Ö.

Journal of Physical Organic Chemistry, cilt.29, sa.4, ss.190-195, 2016 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 29 Sayı: 4
  • Basım Tarihi: 2016
  • Doi Numarası: 10.1002/poc.3517
  • Dergi Adı: Journal of Physical Organic Chemistry
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.190-195
  • Anahtar Kelimeler: acylation of diorganozincs, kinetics of diorganozincs, mixed diorganozincs, phosphine catalyst, CONJUGATE MICHAEL-ADDITIONS, IMPROVED THERMAL-STABILITY, SELECTIVE LIGAND TRANSFER, ORGANIC GROUP-TRANSFER, CARBONYL-COMPOUNDS, GRIGNARD-REAGENTS, DIORGANOZINC COMPOUNDS, ASYMMETRIC-SYNTHESIS, ZINC REAGENTS, ATE COMPLEXES
  • Ankara Üniversitesi Adresli: Evet

Özet

Copyright © 2016 John Wiley & Sons, Ltd.Kinetics of reactions of di-n-butylzinc, n-Bu2Zn, and mixed n-butyl(substituted phenyl)zinc reagents and n-Bu(functional group (FG)-C6H4)Zn with benzoyl chloride in the presence of tri-n-butylphosphine have been investigated. Reaction rates of transferable n-butyl group have been determined in tetrahydrofuran at 0 °C to compare the transfer rate of n-butyl group in homo and mixed diorganozincs. Rate law is consistent with a third-order reaction, which is first order in diorganozinc, benzoyl chloride, and n-Bu3P, and a mechanism was proposed. The lower reaction rate of n-BuPhZn than that of n-Bu2Zn and negative reaction constant in Hammett plot are in accordance with the carbanionic charge of transferable n-butyl group in the acylation reaction. These findings support the hypothesis that the reaction rate of transferable group, RT, changes depending upon the residual group, RR, in RRRTZn reagents.