959075-93-5Relevant academic research and scientific papers
Phosphirenium ions as masked phosphenium Catalysts: Mechanistic evaluation and application in synthesis
Gasperini, Danila,Neale, Samuel E.,Mahon, Mary F.,MacGregor, Stuart A.,Webster, Ruth L.
, p. 5452 - 5462 (2021)
The utilization of phosphirenium ions is presented; optimized and broadened three-membered ring construction is described together with the use of these ions as efficient pre-catalysts for metal-free carbonyl reduction with silanes. Full characterization of the phosphirenium ions is presented, and initial experimental and computational mechanistic studies indicate that these act as a "masked phosphenium"source that is accessed via ring opening. Catalysis proceeds via associative transfer of {Ph2P+} to a carbonyl nucleophile, Ha'SiR3 bond addition over the C=O group, and associative displacement of the product by a further equivalent of the carbonyl substrate, which completes the catalytic cycle. A competing off-cycle process leading to vinyl phosphine formation is detailed for the hydrosilylation of benzophenone for which an inverse order in [silane] is observed. Experimentally, the formation of side products, including off-cycle vinyl phosphine, is favored by electrondonating substituents on the phosphirenium cation, while catalytic hydrosilylation is promoted by electron-withdrawing substituents. These observations are rationalized in parallel computational studies.
Nickel nanoparticles supported on graphene as catalysts for aldehyde hydrosilylation
Blandez, Juan F.,Esteve-Adell, Iván,Primo, Ana,Alvaro, Mercedes,García, Hermenegildo
, p. 13 - 19 (2015/12/08)
Nickel nanoparticles (NPs) supported on different undoped or doped with N or B graphenes (Gs) have been tested as catalyst for the hydrosilylation of aldehydes to obtain the corresponding siloxanes with high conversion and good selectivity in short reaction time. The different Gs employed were obtained by pyrolysis under inert atmosphere of alginate or chitosan, modified or not with boric acid. Then the metal NPs obtained by polyol reduction method using ethylene glycol were adsorbed on Gs. The Ni-containing G catalysts were characterized by electron microscopy, XPS and Raman spectroscopy. The scope of the Ni/G catalyst includes aliphatic and aromatic aldehydes as well as a variety of hydrosilanes.
Enhanced nucleophilic fluorination and radiofluorination of organosilanes appended with potassium-chelating leaving groups
Al-Huniti, Mohammed H.,Lu, Shuiyu,Pike, Victor W.,Lepore, Salvatore D.
, p. 48 - 52 (2014/01/23)
Here we aimed to explore the feasibility of enhancing the fluorination of organosilanes by appending potassium-chelating groups to the substrates. For this purpose, eight organosilanes were prepared in which a linear or cyclic leaving group, with putative
