Well-defined PEPPSI-themed palladium-NHC complexes: synthesis, and catalytic application in the direct arylation of heteroarenes
APPLIED ORGANOMETALLIC CHEMISTRY, vol.34, no.2, 2020 (SCI-Expanded, Scopus)
- Publication Type: Article / Article
- Volume: 34 Issue: 2
- Publication Date: 2020
- Doi Number: 10.1002/aoc.5387
- Journal Name: APPLIED ORGANOMETALLIC CHEMISTRY
- Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, BIOSIS, Chimica, Communication Abstracts, Compendex, Metadex, DIALNET, Civil Engineering Abstracts
- Keywords: direct arylation, heteroarene, N-heterocyclic carbene, palladium, PEPPSI, HETEROCYCLIC CARBENE COMPLEXES, CROSS-COUPLING REACTIONS, C-H FUNCTIONALIZATION, ARYL BROMIDES, REACTIVITY, CHLOROPYRAZINES, HETEROAROMATICS, PRECATALYST, ACTIVATION, CARBONATE
- Inonu University Affiliated: Yes
Abstract
In this study, a series of benzimidazolium salts were synthesized as unsymmetrical N-heterocyclic carbene (NHC) precursors. Benzimidazolium salts were used for synthesis of the PEPPSI (pyridine enhanced precatalyst preparation stabilization and initiation)-themed, six new Pd-complexes with the general formula [PdX2(NHC)(pyridine)]. The structures of all compounds were characterized by various spectroscopic techniques such as H-1 NMR, C-13 NMR and FT-IR. The more detailed structural characterization of four of the complexes was determined by single-crystal X-ray diffraction study. The catalytic activities of all Pd-complexes were evaluated in the direct arylation of the 2-acetylfuran and 2-acetylthiophene with aryl bromides in the presence of 1 mol% catalyst loading.