Swart, Marthinus R.; Twigge, Linette; Erasmus, Elizabeth; Marais, Charlene; Bezuidenhoudt, Barend C. B. published an article in 2021. The article was titled 《Olefin Metathesis, p-Cresol, and the Second Generation Grubbs Catalyst: Fitting the Pieces》, and you may find the article in European Journal of Inorganic Chemistry.Name: Ethyltriphenylphosphonium bromide The information in the text is summarized as follows:
P-Cresol as additive to the Grubbs second generation catalyst (GII) allows the cross-metathesis of acrylates with prop-1-en-1-ylbenzenes under conditions that only give the prop-1-en-1-ylbenzene self-metathesis product in the absence of cresol. NMR and IR spectroscopy, MALDI-TOF MS and XPS supported the formation of a ruthenium benzylidene with hydrogen bonds between p-cresol and the chloride ligands of GII. XPS furthermore confirmed p-cresol to increase the binding energies of the GII Ru 3d5/2, 3d3/2, 3p3/2 and 3p1/2 photoelectron lines, whereas 1H NMR spectroscopy indicated the carbene carbon and hydrogen to be shielded. It is thus postulated that p-cresol allows for more facile interaction between electron-deficient compounds and the ruthenium benzylidene by decreasing the electron d. on the metal center and increasing the electron d. on the carbene. Safety: toxic thallium compounds In the part of experimental materials, we found many familiar compounds, such as Ethyltriphenylphosphonium bromide(cas: 1530-32-1Name: Ethyltriphenylphosphonium bromide)
Ethyltriphenylphosphonium bromide(cas: 1530-32-1) is a phase transfer catalyst, used to accelerate the cure of phenolic-based epoxy resins, certain fluoroelastomer resins and thermosetting powder coatings. CatOnium ETPB is also used as catalysts in the synthesis of certain organic compounds.Name: Ethyltriphenylphosphonium bromide
Referemce:
Bromide – Wikipedia,
bromide – Wiktionary