Abstract The interaction of the benzimidazolium salt with Ag2O in dichloromethane to prepare novel Ag(I)-N-heterocyclic carbene complexes has been carried out at room temperature for 48 h in the absence of light. The obtained complexes were identified and characterized by 1H and 13C NMR, FT-IR and elemental analysis techniques. In addition, it has been found that some of the complexes are antimicrobially
Cationic NHC‐Phosphine Iridium Complexes: Highly Active Catalysts for Base‐Free Hydrogenation of Ketones
作者:Xu Quan、Sutthichat Kerdphon、Bram B. C. Peters、Janjira Rujirawanich、Suppachai Krajangsri、Jira Jongcharoenkamol、Pher G. Andersson
DOI:10.1002/chem.202002811
日期:2020.10.15
evaluated in the hydrogenation of ketones. Reported catalytic systems require base additives and, if excluded, need elevated temperature or high pressure of hydrogen gas to achieve satisfactory reactivity. The developed catalysts showed extremely high reactivity and good enantioselectivity under base‐free and mild conditions. In the presence of 1 mol % catalyst under 1 bar hydrogen pressure at room
Intermediates of N‐Heterocyclic Carbene (NHC) Dimerization Probed in the Gas Phase by Ion Mobility Mass Spectrometry: C−H⋅⋅⋅:C Hydrogen Bonding Versus Covalent Dimer Formation
covalent C−C bond (CCH+). In this study, the intramolecular NHC–azolium salt interactions of aromatic imidazolin‐2‐ylidenes and saturated imidazolidin‐2‐ylidenes have been investigated in the gasphase by traveling wave ion mobility mass spectrometry (TW IMS) and DFT calculations. The TW IMS experiments provided evidence for the formation of these important intermediates in the gasphase, and they identified
reaction paths and intermediate structures related to the formation of the Breslow intermediate and its oxidation along the oxidative/oxygenative lanes have been studied from a mechanistic point of view, with the support of gas-phase and computational studies. The results confirm the occurrence of a single-electron transfer from the Breslow intermediate to the molecular oxygen with formation of a radical
Preparation and characterization of PEPPSI-palladium <i>N</i>-heterocyclic carbene complexes using benzimidazolium salts catalyzed Suzuki–Miyaura cross coupling reaction and their antitumor and antimicrobial activities
Abstract New palladium complexes were efficiently synthesized from the reaction of benzimidazolium salts 2a–e, potassium carbonate (K2CO3) and palladium chloride (PdCl2) in pyridine (for 3a–e). The catalytic activity of these complexes in a catalytic system including palladium complexes and K2CO3 in DMF-H2O was evaluated in Suzuki–Miyaura cross-coupling reactions of aryl bromides and chlorides with