Applications of quinoxaline-bridged bis(benzimidazolium) salts as ligand sources for the palladium-catalyzed Suzuki and Heck cross-coupling reactions in an aqueous medium


DEMİR DÜŞÜNCELİ S., Sahan M. H. , KALOĞLU M., ÜSTÜN E., ÖZDEMİR İ.

JOURNAL OF THE CHINESE CHEMICAL SOCIETY, 2022 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Publication Date: 2022
  • Doi Number: 10.1002/jccs.202200304
  • Journal Name: JOURNAL OF THE CHINESE CHEMICAL SOCIETY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, CAB Abstracts, Chemical Abstracts Core, INSPEC
  • Keywords: bis(benzimidazolium) salt, Heck coupling, N-heterocyclic carbene, palladium, quinoxaline, Suzuki coupling, N-HETEROCYCLIC CARBENE, PALLADIUM/IMIDAZOLIUM SALT, ARYL BROMIDES, PRECURSORS SYNTHESIS, COMPLEXES SYNTHESIS, OLEFIN METATHESIS, KINETIC STABILITY, PHOSPHINE-LIGANDS, BOND FORMATION, BASIS-SETS
  • Inonu University Affiliated: Yes

Abstract

In the present work, quinoxaline-bridged bis(benzimidazolium) salts were prepared by the reaction of 2,3-bis(bromomethyl) quinoxaline and 1-substituted benzimidazole. The structures of the bis(benzimidazolium) salts were characterized by NMR, FT-IR, and elemental analysis techniques. Also, the photophysical properties of salts were investigated by UV-Vis absorption and fluorescence emission spectroscopy. Next, these quinoxaline bridged bis(benzimidazolium) salts were used as bidentate benzimidazol-2-ylidene ligand precursors in the palladium-catalyzed Suzuki-Miyaura and Mizoroki-Heck cross-couplings. These salts exhibited moderate-to-high activity in the palladium-catalyzed cross-coupling reactions.