Quality Control of Tricyclohexylphosphonium tetrafluoroborate. So far, in addition to halogen atoms, other non-metallic atoms can become part of the aromatic heterocycle, and the target ring system is still aromatic. Compound: Tricyclohexylphosphonium tetrafluoroborate, is researched, Molecular C18H34BF4P, CAS is 58656-04-5, about Mechanistic Investigation of the Ruthenium-N-Heterocyclic-Carbene-Catalyzed Amidation of Amines with Alcohols.
The mechanism of the ruthenium-N-heterocyclic-carbene-catalyzed formation of amides from alcs. and amines was investigated by exptl. techniques (Hammett studies, kinetic isotope effects) and by a computational study with dispersion-corrected d. functional theory (DFT/M06). The Hammett study indicated that a small pos. charge builds-up at the benzylic position in the transition state of the turnover-limiting step. The kinetic isotope effect was determined to be 2.29(±0.15), which suggests that the breakage of the C-H bond is not the rate-limiting step, but that it is one of several slow steps in the catalytic cycle. Rapid scrambling of hydrogen and deuterium at the α position of the alc. was observed with deuterium-labeled substrates, which implies that the catalytically active species is a ruthenium dihydride. The exptl. results were supported by the characterization of a plausible catalytic cycle by using DFT/M06. Both cis-dihydride and trans-dihydride intermediates were considered, but when the theor. turnover frequencies (TOFs) were derived directly from the calculated DFT/M06 energies, we found that only the trans-dihydride pathway was in agreement with the exptl. determined TOFs.
《Mechanistic Investigation of the Ruthenium-N-Heterocyclic-Carbene-Catalyzed Amidation of Amines with Alcohols》 provides a strategy for the preparation of materials with excellent comprehensive properties, which is conducive to broaden the application field of this compound(Tricyclohexylphosphonium tetrafluoroborate)Quality Control of Tricyclohexylphosphonium tetrafluoroborate.
Reference:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem