185509-29-9Relevant academic research and scientific papers
APPLICATION OF STAUDINGER LIGATION IN PET IMAGING
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Page/Page column 18; 23, (2011/10/13)
A method for generating a radiolabeled tracer. The method includes providing a phosphine molecule having at least one carbocyclic, aromatic, or pyrrolidinyl ring with an OH substitute. The OH of this phosphines molecule is then condensed with an acid to p
O-Acylated 2-Phosphanylphenol Derivatives - Useful ligands in the Nickel- Catalyzed polymerization of ethylene
Yakhvarov, Dmitry G.,Basvani, Kaleswara R.,Khiderniann, Markus K.,Dobrynin, Alexey B.,Litvinov, Igor A.,Sinyashin, Oleg G.,Jones, Peter G.,Heinicke, Joachim
body text, p. 1234 - 1242 (2009/06/06)
The title ligands were prepared by O-acylation of 2-di- phenylphosphanyl-4-methylphenol (1) or directly by double lithiation of 2-bromo-4-methylphenol and stepwise coupling with ClPPh2 and ClP(O)Ph2 or RC(O))C1 (R = Me, tBu, Ph, 4-MeOC6H 4) to afford diphenylphosphinate 2 and carboxylic esters 3a-d. X-ray crystal structure analyses of 3b-d show conformations in which the P-phenyl substituents are rotated away from the ester group and the C(O)O π planes are nearly perpendicular to the phenol ring π plane. O-Acylated phosphanylphenols 2 and 3a-d form highly active catalysts with Ni(l,5-cod) 2 (as does 1) for polymerization of ethylene, whereas phosphanylphenyl ethers do not give catalysts under the same conditions. The reason is the cleavage of the O-acyl bond upon heating with nickel(O) precursor compounds in the presence of ethylene. The precursors are P- coordinated Ni 0 complexes, which are formed at room temperature, such as 4d obtained from 3d and Ni(cod)2 in a 2:1(molar ratio), and characterized by multinuclear NMR spectroscopy. Upon heating in the presence of ethylene, the pre-catalysts are activated. Catalysts2Ni and 3a-d Ni convert ethylene nearly quantitatively, 2Ni slowly, and 3a-dNi rapidly, into linear polyethylene with vinyl and methyl end groups, and in the latter case, C(O)R end groups are also detectable. This proves insertion of Ni0into the O-C(O)R bond of 3a-d ligands for formation of the primary catalyst. Termination of the first chain growing cycle by β-hydride elimination changes the mechanism to the phosphanylphenolate- NiH initiated polymerization providing the main body of the polymer. A small retardation in the ethylene consumption rate with 3a-dNi, catalysts relative to that observed for lNi and stabilization of the catalyst, which gives rise to reproducibly high ethylene conversion, is observed.
Synthesis and reactivity of bimetallic palladium(II) methyl complexes with new functional phosphine ligands
Kim, Jang Sub,Sen, Ayusman,Guzei, Ilia A.,Liable-Sands, Louise M.,Rheingold, Arnold L.
, p. 4726 - 4731 (2007/10/03)
Bimetallic palladium(II) methyl complexes, [Pd(dppmpH)(CH3)(μ-Cl)]2 (1) and [Pd(dippmpH)(CH3)(μ-Cl)]2 (2) were synthesized by the reaction of (COD)Pd(CH3)(Cl) (COD = 1,5-cyclooctadiene) with the new functional phosphine ligands 2-diphenylphosphino-4-methylphenol (dppmpH) and 2-diisopropylphosphino-4-methylphenol (dippmpH). The homolytic cleavage of the CH3-Pd bond was found to occur when complexes 1 and 2 were heated or photolyzed to form a methyl radical and the corresponding oxygen-bridged bimetallic palladium(II) complexes, [Pd(dppmp)(Cl)]2 (3) and [Pd(dippmp)(Cl)]2 (4), respectively. The molecular structures of complexes 1, 3 and 4 were determined by single-crystal X-ray diffraction. Reaction of small molecules, such as CO, SO2 and CH2=CH2, with complexes 1 and 2 was observed and characterized by IR, 1H, 13C and 31P{1H} NMR spectroscopy.
Complexes of phosphine-phenolate ligands with the [Re=O]3+ and [Re(HNNC5H4N)(NNC5H4N)] 2+ cores
Kovacs,Hein,Sattarzadeh,Patrick,Emge,Orvig
, p. 3015 - 3024 (2007/10/03)
Complexes incorporating the [Re=O]3+ core have been synthesised with ligands containing the new methyl substituted phosphine - Phenolate PO and PO2 donor sets, (2-hydroxy-5-methylphenyl)diphenylphosphine (H(MePO)) and bis(2-hydroxy-5
P/O ligand systems: Synthesis, reactivity, structure of tertiary o-phosphanylphenol derivatives
Heinicke, Joachim,Kadyrov, Renat,Kindermann, Markus K.,Koesling, Manuela,Jones, Peter G.
, p. 1547 - 1560 (2007/10/03)
Reactions of C,O-dilithium reagents 1 (M = M′ = Li) or C,O-lithium-sodium reagents 1 (M = Li, M′ = Na) with chlorophosphanes afford C,O-disubstitution products 2 or phosphanylphenolates 3 which are treated subsequently with ClSiMe3 to give 4-me
