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Baber RA Clarke ML Heslop KM Marr AC Orpen AG Pringle PG Ward A Zambrano-Williams DE 《Dalton transactions (Cambridge, England : 2003)》2005,(6):1079-1085
The cage phosphines 1,3,5,7-tetramethyl-6-phenyl-2,4,8-trioxa-6-phosphaadamantane (1a) and 1,3,5,7-tetraethyl-6-phenyl-2,4,8,trioxa-6-phosphaadamantane (1b) have been made by the acid catalysed addition of PhPH(2) to the appropriate beta-diketones; the acid used (HCl, H(3)PO(4) or H(2)SO(4)) and its concentration affect the rate and selectivity of these condensation reactions. Phosphines 1a and 1b react with [PdCl(2)(NCPh)(2)] to form complexes trans-[PdCl(2)(1a)(2)](2a) and trans-[PdCl(2)(1b)(2)](2b) as mixtures of rac and meso diastereoisomers. The platinum(II) chemistry is more complicated and when 1a or 1b is added to [PtCl(2)(cod)], equilibrium mixtures of trans-[PtCl(2)L(2)] and [Pt(2)Cl(4)L(2)](L = or ) are formed in CH(2)Cl(2) solution. Meso/rac mixtures of trans-[MCl(CO)(1a)(2)] M = Ir (6a) or Rh (7a) are formed upon treatment of MCl(3).nH(2)O with an excess of 1a and the anionic cobalt complex [NHEt(3)][CoCl(3)(1a)](9) was isolated from the product formed by CoCl(2).6H(2)O and 1a. The nu(CO) values from the IR spectra of 6a and 7a suggest that 1a resembles a phosphonite in its bonding to Rh and Ir. Crystal structures of meso-2a, meso-2b, rac-6a and 9 are reported and in each case a small intracage C-P-C angle of ca. 94 degrees is observed; this may partly explain the bonding characteristics of ligands 1a and 1b. The cone angles for 1a and 1b are similar and large (ca. 200 degrees). Rhodium complexes of ligands 1a and 1b are hydroformylation catalysts with similarly high activity to catalysts derived from phosphites. The catalysts derived from 1a and 1b gave unusually low linear selectivity in the hydroformylation of hexenes. This feature has been further exploited in quaternary-selective hydroformylations of unsaturated esters; catalysts derived from 1a give better yields and regioselectivities than any previously reported catalyst. 相似文献
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Kirsty J. Pringle J. Christopher Whitehead Jonathan J. Wilman Jinhui Wu 《Plasma Chemistry and Plasma Processing》2004,24(3):421-434
The destruction of methane by a nonthermal plasma in atmospheric pressure gas streams of nitrogen with variable amounts of added oxygen has been investigated. The identities and concentrations of the endproducts are determined by online FTIR spectroscopy and the plasma chemistry is interpreted using kinetic modelling. For a deposited energy of 118 kJ m–3, the destruction is 12% in nitrogen decreasing monotonically to 5% in air. The major endproducts are HCN and NH3 in nitrogen and CO, CO2, N2O, NO and NO2 for gas streams containing oxygen. The chemistry in pure nitrogen is predominantly due to reactions of electronicallyexcited nitrogen atoms, N(2D). The addition of oxygen converts the excited state nitrogen into nitrogen oxides reducing the methane destruction which then arises by O and OH reactions yielding CO and, to a lesser extent, CO2. The modelling correctly predicts the magnitude of the methane destruction as a function of added oxygen and the concentrations of the endproducts for processing in both nitrogen and air. 相似文献
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Single Oxygen‐Atom Insertion into PB Bonds: On‐ and Off‐Metal Transformation of a Borylphosphine into a Borylphosphinite 下载免费PDF全文
Jonathan A. Bailey Dr. Hazel A. Sparkes Prof. Dr. Paul G. Pringle 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(14):5360-5363
An oxygen atom is selectively inserted into the P?B bond of a borylphosphine ( L1 ) by reaction with Me3NO to afford the corresponding borylphosphinite ( L2 ). This transformation can also be effected when L1 is coordinated to rhodium. The ν(CO) values for trans‐[RhCl(CO)(L)2] reveal very different electronic properties for coordinated L1 and L2 which translate into the strikingly different performances of the complexes [RhCl(L)(cod)] (L= L1 or L2 , cod=1,5‐cyclooctadiene) in hydrosilylation and hydroboration catalysis. 相似文献
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Abraham TJ MacFarlane DR Pringle JM 《Chemical communications (Cambridge, England)》2011,47(22):6260-6262
Measurement of Seebeck coefficients in a range of ionic liquids (ILs) suggests that these electrolytes could enable the development of thermoelectric devices to generate electrical energy from low-grade heat in the 100-150 °C range. 相似文献
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