29149-93-7Relevant articles and documents
Measurement of the hydride donor abilities of [HM(diphosphine)2]+ complexes (M = Ni, Pt) by heterolytic activation of hydrogen
Curtis, Calvin J.,Miedaner, Alex,Ellis, William W.,DuBois, Daniel L.
, p. 1918 - 1925 (2002)
[M(diphosphine)2]2+ complexes (where M = Ni and Pt) react with hydrogen in the presence of bases to form the corresponding hydrides, [HM(diphosphine)2]+. In seven cases, equilibria have been observed from which
Protonation studies of a tungsten dinitrogen complex supported by a diphosphine ligand containing a pendant amine
Weiss, Charles J.,Egbert, Jonathan D.,Chen, Shentan,Helm, Monte L.,Bullock, R. Morris,Mock, Michael T.
, p. 2189 - 2200 (2014/06/09)
Treatment of trans-[W(N2)2(dppe)(PEtN MePEt)] (dppe = Ph2PCH2CH 2PPh2; PEtNMePEt = Et2PCH2N(Me)CH2PEt2) with 3 equiv of tetrafluoroboric acid (HBF4·Et2O) at °78 °C generated the seven-coordinate tungsten hydride trans-[W(N 2)2(H)(dppe)(PEtNMeP Et)][BF4]. At higher temperatures, protonation of a pendant amine is also observed, affording trans-[W(N2) 2(H)(dppe)(PEtNMe(H)PEt)][BF 4]2, with formation of the hydrazido complex [W(NNH 2)(dppe)(PEtNMe(H)PEt)][BF 4]2 as a minor product. A similar product mixture was obtained using triflic acid (HOTf). The protonated products are thermally sensitive and do not persist at ambient temperature. Upon acid addition to the carbonyl analogue cis-[W(CO)2(dppe)(PEtN MePEt)], the seven-coordinate carbonyl hydride complex trans-[W(CO)2(H)(dppe)(PEtNMe(H)P Et)][OTf]2 was generated. A mixed diphosphine complex without the pendant amine in the ligand backbone, trans-[W(N2) 2(dppe)(depp)] (depp = Et2P(CH2) 3PEt2), was synthesized and treated with HOTf, selectively generating a hydrazido complex, [W(NNH2)(OTf)(dppe)(depp)][OTf]. Computational analysis probed the proton affinity of three sites of protonation in these complexes: the metal, pendant amine, and N2 ligand. Room-temperature reactions with 100 equiv of HOTf produced NH4 + from reduction of the N2 ligand (electrons come from W). The addition of 100 equiv of HOTf to trans-[W(N2) 2(dppe)(PEtNMePEt)] afforded 0.81 equiv of NH4+, while 0.40 equiv of NH4 + was formed upon treatment of trans-[W(N2) 2(dppe)(depp)] with HOTf, showing that the complexes containing proton relays produce more products of reduction of N2.
Catalytic activity of cationic diphospalladium(II) complexes in the alkene/CO copolymerization in organic solvents and water in dependence on the length of the alkyl chain at the phosphine ligands
Lindner, Ekkehard,Schmid, Markus,Wald, Joachim,Queisser, Joachim A.,Gepr?gs, Michael,Wegner, Peter,Nachtigal, Christiane
, p. 173 - 187 (2007/10/03)
A series of diphos ligands CH2(CH2PR2)2 (1a-x) (a-g: R=(CH2)nOH, n=1, 3-8; h-k: R=(CH2)nCH(CH2OH)2, n=3-6; l-u: R=CnH2n+1, n=1-8, 10, 14; v-x: R=CH(CH3)2, (CH2)2CH(CH3)2, (CH2)3CH(CH3)2, (Scheme 1), provided with functionalities of different polarity, was prepared photochemically by hydrophosphination of the corresponding 1-alkenes with H2P(CH2)3PH2 or reaction of Grignard reagents with Cl2P(CH2)3PCl2. The water-soluble palladium complexes [(R2P(CH2)3PR2)Pd(OAc)2] (2a-k) were obtained by reaction of Pd(OAc)2 with the ligands 1a-k in ethanol-acetonitrile. Treatment of PdCl2(NCC6H5)2 with 1l-x afforded the dichloropalladium(II) complexes [(R2P(CH2)3PR2)PdCl2] (3l-x). Upon chloride abstraction with AgBF4 in dichloromethane-acetonitrile the dicationic palladium(II) complexes [(R2P(CH2)3PR2)Pd(NCCH 3)2][BF4]2 (4l-x) are formed. The structure of 4n (R=n-Pr) was investigated by an X-ray structural analysis. In particular the water-soluble complexes 2c-k proved to be highly active in the carbon monoxide/ethene copolymerization under biphasic conditions (water-toluene). In the presence of an emulsifier and methanol as activator the catalytic activity increased by a factor of about three. Also higher olefins could be successfully incorporated into the copolymerization with CO and the terpolymerization with ethene and CO. The catalytic activity of the dicationic complexes 4l-x in the propene or 1-hexene/CO copolymerization strongly depends on the length of the alkyl chain R. At 25°C a maximum is achieved in the case of 4q (R=nHex) which is five times more active than the corresponding catalyst with the dppp-ligand. This maximum is shifted to 4t (R=n-C10H21) if the temperature is raised to 60°C. The 1-alkene/CO copolymers are distinguished by their regioregular microstructure and their ultra high molecular weights. Compared to the sulfonated dppp-SO3 catalyst the water-soluble complexes 2c,e,f,h are responsible for a higher 1-hexene incorporation in the terpolymerization of ethene with 1-hexene and CO.
Co-dimerization of vinyl aromatics with α-monoolefins
-
, (2008/06/13)
The invention concerns a process for the co-dimerization of a vinyl aromatic monomer (e.g. styrene) with an α-monoolefin monomer (e.g. ethylene, propylene or 1-butylene), using a catalyst composition comprising palladium, an anion of a strong acid and an aliphatic diphosphine.
Notes Unsymmetrical Bis(phosphorus) Compounds: Synthesis of Unsymmetrical Ditertiary Phosphines, Phosphine Oxides, and Diquaternary Phosphonium Salts
Benn, Roger F.,Briggs, Josie C.,McAuliffe, Charles A.
, p. 293 - 296 (2007/10/02)
A convenient preparative route to the unsymmetrical bidentate phosphines R2P(CH2)nPPh2 (R=Me or Et; n=3 or 4) is described.This involves the synthesis of unsymmetrical diphosphonium salts, Br2, and diphosphine oxides, R2P(O)(CH2)nPPh2, as intermediates.The symmetrical ligand Et2P(CH2)3PEt2 was also prepared by the same route.New co-ordination complexes of manganese(II) with these ligands have been isolated.
