In this study, a series of benzimidazolium salts were synthesized as asymmetric N-heterocyclic carbene (NHC) precursors. Nine novel palladium complexes with the general formula [PdX2(NHC)(pyridine)] were synthesized using benzimidazolium salts in the PEPPSI (Pyridine Enhanced Precatalyst Preparation, Stabilization and Initiation) theme. All synthesized Pd(II) complexes are stable. The synthesized compounds were thoroughly characterized by respective spectroscopic techniques, such as 1HNMR, 13C NMR, FTIR spectroscopy, X-ray crystallography and elemental analysis. The geometric structure of the palladium N-heterocyclic carbene has been optimized in the framework of density functional theory (DFT) using the B3LYP-D3 dispersion functional with LANL2DZ as a basis set. The on/off mechanism of pyridine assisted Pd–NHC complexes made them the best C–H functionalized catalysts for regioselective C-5 arylated products. Five membered heterocyclic compounds such as 2-acetyl furan, furfuryl acetate 2-acetylthiophene and N-methylpyrrole-2-carboxaldehyde were treated with numerous aryl bromides and arylchlorides under optimal catalytic reaction conditions. Interestingly, all the prepared catalysts possessed essential structural features that facilitated the formation of desired coupling products in quantitative yield with excellent selectivity. The arylation reaction of bromoacetophenone was highly catalytically active with only 1 mol% catalyst loading at 150 °C for 2 hours. To check the efficiency of the synthesized complexes, three different five member heterocyclic substrates (2-acetylfuran, 2-acetylthiophen, 2-propylthaizole) were tested with a number of aryl bromides bearing both electron-donating and electron-withdrawing groups on para position. The data in Tables 2–4. Indicated that electron-donating groups on the para position of aryl halide decreased the catalytic conversion while electron-withdrawing groups increased the catalytic conversion this was due to the high nucleophilicity of the electron-donating substituents.
Authors
D. Bensalah, L. Mansour, Mathieu Sauthier, N. Gurbuz, I. Özdemir, L. Beji, R. Gatri, N. Hamdi
- Bibliographic Reference
- D. Bensalah, L. Mansour, Mathieu Sauthier, N. Gurbuz, I. Özdemir, et al.. Plausible PEPPSI catalysts for direct C-H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray crystallographic characterizations and catalytic activity.. RSC Advances, 2023, RSC Adv, 13 (45), pp.31386-31410. ⟨10.1039/d3ra06334h⟩. ⟨hal-04311682⟩
- DOI
- https://doi.org/10.1039/d3ra06334h
- HAL Collection
- ["Université d'Artois", 'CNRS - Centre national de la recherche scientifique', 'Unité de Catalyse et de Chimie du Solide', 'Institut de Chimie du CNRS', 'Université de Lille']
- HAL Identifier
- 4311682
- Institution
- ['King Saud University [Riyadh]', "Université d'Artois", 'Centrale Lille', 'Institut de Chimie - CNRS Chimie', 'Inönü University', 'Qassim University [Kingdom of Saudi Arabia]']
- Laboratory
- Unité de Catalyse et Chimie du Solide - UMR 8181
- Published in
- France
Table of Contents
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
- Plausible PEPPSI catalysts for direct Ctnqh_x2013H functionalization of five-membered heterocyclic bioactive motifs: synthesis, spectral, X-ray... 0
