5864-22-2Relevant academic research and scientific papers
Hydrosilylation of ketones, imines and nitriles catalysed by electrophilic phosphonium cations: Functional group selectivity and mechanistic considerations
Pérez, Manuel,Qu, Zheng-Wang,Caputo, Christopher B.,Podgorny, Vitali,Hounjet, Lindsay J.,Hansen, Andreas,Dobrovetsky, Roman,Grimme, Stefan,Stephan, Douglas W.
supporting information, p. 6491 - 6500 (2015/04/22)
The electrophilic phosphonium salt, [(C6F5)3PF][B(C6F5)4], catalyses the efficient hydrosilylation of ketones, imines and nitriles at room temperature. In the presence of this catalyst, adding one equivalent of hydrosilane to a nitrile yields a silylimine product, whereas adding a second equivalent produces the corresponding disilylamine. [(C6F5)3PCl][B(C6F5)4] and [(C6F5)3PBr][B(C6F5)4] are also synthesised and tested as catalysts. Competition experiments demonstrate that the reaction exhibits selectivity for the following functional groups in order of preference: ketone>nitrile>imine>olefin. Computational studies reveal the reaction mechanism to involve initial activation of the Si-H bond by its interaction with the phosphonium centre. The activated complex then acts cooperatively on the unsaturated substrate. Proceed with cation: The electrophilic phosphonium salt, [(C6F5)3PF][B(C6F5)4], catalyses the efficient hydrosilylation of ketones, imines and nitriles at room temperature. In the presence of this catalyst, adding one equivalent of hydrosilane to a nitrile yields a silylimine product, whereas adding a second equivalent produces the corresponding disilylamine.
Structure of R3PCl2 compounds in the solid state and in solution: Dependency of structure on R. Crystal structures of trigonal bipyramidal (C6F5)3PCl2, Ph2(C6F5)PCl2 and of ionic Prn3PCl2
Godfrey, Stephen M.,McAuliffe, Charles A.,Pritchard, Robin G.,Sheffield, Joanne M.,Thompson, Graeme M.
, p. 4823 - 4827 (2007/10/03)
A number of triorganophosphorus dichloride compounds R3PCl2, (R3 = substituted aryl, mixed aryl-alkyl or triaryl) have been synthesized from diethyl ether solution and characterised by analytical and 31P-{1H} NMR data in CDCl3 solution. The majority of the compounds are ionic, [R3PCl]Cl, in CDCl3 solution, in keeping with analogous species containing the heavier halogens [R3PX]X (X = Br or I), according to 31P-{1H} NMR studies. In contrast, the compounds R3PCl2 [R3 = (C6F5)3 or (C6F5)Ph2] have a molecular five-co-ordinate trigonalbipyramidal structure both in CDCl3 solution and in the solid state. The crystal structures of these two compounds have been determined and represent the only crystallographic studies of trigonal-bipyramidal compounds of stoichiometry R3PCl2. The compound (C6F5)3PCl2 exhibits almost perfect trigonal-bipyramidal geometry, whereas (C6F5)Ph2PCl2 shows significant distortion. This may be due to the asymmetry of the equatorial groups around the phosphorus atom. Why R3PCl2 [R3 = (C6F5)3 or (C6F5)Ph2] adopt a trigonal-bipyramidal structure is reasoned to be due to the acidity of the parent tertiary phosphines, which favours this geometry for the dihalogen adducts, a phenomenon previously observed for dihalogen adducts of tertiary arsines. The crystal structure of Prn3PCl2, the first crystallographically characterised example of an ionic R3PCl2 compound which does not contain a solvent molecule, has been found to contain two Prn3PCl2 entities. The first consists of an ionic [Prn3PCl]+ unit weakly linked by a long Cl ... Cl contact to a Cl-, d(Cl ... Cl) 3.207(3) A. The second shows a discrete [Prn3PCl]+ cation, the Cl- anion being associated with δ+ H atoms on a [Prn3PCl]+ moiety. This compound was prepared and crystallised from diethyl ether and its relation to the solvated complex [Ph3PCl ... Cl ... ClPPh3]Cl·CH2Cl2 is discussed.
The Acceptor Properties of some Pentafluorophenylphosphorous(V) Species
Ali, Rusmidah,Dillon, Keith B.
, p. 1375 - 1381 (2007/10/02)
The acceptor properties of P(C6F5)nCl5-n (1 + (1 + towards Lewis bases, such as the chloride ion and uni- and bi-dentate pyridines, have been investigated.Several new complexes have been isolated, and characterised by elemental analysis and (in some cases) 31P n.m.r. and/or i.r. spectroscopy.
