Dichlorido(3-chloropyridine-N)[1,3-dialkylbenzimidazol-2-ylidene] palladium(II) complexes: Synthesis, characterization and catalytic activity in the arylation reaction


Akkoc S. , GÖK Y.

INORGANICA CHIMICA ACTA, vol.429, pp.34-38, 2015 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 429
  • Publication Date: 2015
  • Doi Number: 10.1016/j.ica.2015.01.019
  • Title of Journal : INORGANICA CHIMICA ACTA
  • Page Numbers: pp.34-38
  • Keywords: PEPPSI palladium complexes, N-Heterocyclic carbene, Benzimidazole, Catalyst, Direct arylation, N-HETEROCYCLIC CARBENE, HIGHLY EFFICIENT CATALYSTS, PD-PEPPSI COMPLEXES, PRECATALYST ACTIVATION, NHC, COUPLINGS

Abstract

Six novel Pyridine Enhanced Precatalyst Preparation, Stabilization and Initiation (PEPPSI) themed palladium N-heterocyclic carbene (Pd-NHC) complexes (2a-f) were synthesized in good yields from the reaction of 1,3-dialkylbenzimidazolium salts with PdCl2 in the presence of K2CO3 as base in 3-chloropyridine. These synthesized complexes were characterized by means of elemental analysis, FT-IR, H-1 and C-13 NMR spectroscopic methods. The fully characterized novel complexes (2a-f) were tested as catalysts in the direct arylation of 2-n-propylthiazole, 2-n-butylthiophene and 2-n-butylfuran with different aryl bromides at 130 degrees C for 1 h. The complexes exhibited fairly high catalytic activities under the given conditions. The highest conversions were achieved when complexes 2a, 2e and 2f were used as catalysts in direct arylation. (C) 2015 Elsevier B.V. All rights reserved.