27286-19-7Relevant academic research and scientific papers
Aromatic vs aliphatic C-H bond activation by rhodium(I) as a function of agostic interactions: Catalytic H/D exchange between olefins and methanol or water
Rybtchinski, Boris,Cohen, Revital,Ben-David, Yehoshoa,Martin, Jan M. L.,Milstein, David
, p. 11041 - 11050 (2003)
The aryl-PC type ligand 3, benzyl(di-tert-butyl)phosphane, reacts with [Rh(coe)2(solv)n]BF4 (coe = cyclooctene, solv = solvent), producing the C-H activated complexes 4a-c (solv = (a) acetone, (b) THF, (c) methanol). Complexes 4a-c undergo reversible arene C-H activation (observed by NMR spin saturation transfer experiments, SST) and H/D exchange into the hydride and aryl ortho-H with ROD (R = D, Me). They also promote catalytic H/D exchange into the vinylic C-H bond of olefins, with deuterated methanol or water utilized as D-donors. Unexpectedly, complex 2, based on the benzyl-PC type ligand 1 (analogous to 3), di-tert-butyl(2,4,6-trimethylbenzyl)phosphane, shows a very different reversible C-H activation pattern as observed by SST. It is not active in H/D exchange with ROD and in catalytic H/D exchange with olefins. To clarify our observations regarding C-H activation/reductive elimination in both PC-Rh systems, density functional theory (DFT) calculations were performed. Both nucleophilic (oxidative addition) and electrophilic (H/D exchange) C-H activation proceed through η2-C,H agostic intermediates. In the aryl-PC system the agostic interaction causes C-H bond acidity sufficient for the H/D exchange with water or methanol, which is not the case in the benzyl PC-Rh system. In the latter system the C-H coordination pattern of the methyl controls the reversible C-H oxidative addition leading to energetically different C-H activation processes, in accordance with the experimental observations.
One-Pot Synthesis of 1,3-Bis(phosphinomethyl)arene PCP/PNP Pincer Ligands and Their Nickel Complexes
Shih, Wei-Chun,Ozerov, Oleg V.
, p. 4591 - 4597 (2015/10/06)
A one-pot synthesis of arene-based PCP/PNP ligands has been developed. The reaction of 1,3-bis(bromomethyl)benzene or 2,6-bis(bromomethyl)pyridine with various chlorophosphines in acetonitrile afforded bis-phosphonium salts. These salts can then be reduced by magnesium powder to yield PCP or PNP ligands. In comparison to traditional synthetic methods for making PCP/PNP ligands involving the use of secondary phosphines, this new alternative method allows for the use of chlorophosphines, which are cheaper, safer to handle, and have a broader range of commercially available derivatives. This is especially true for the chlorophosphines with less bulky alkyl groups. Moreover, the one-pot procedure can be extended to allow for the direct synthesis of PCP/PNP nickel complexes. By using nickel powder as the reductant, the resulting nickel halide was found to directly undergo metalation with the PCP or PNP ligand to generate nickel complexes in high yields.
Electroluminescent iridium compounds with silylated, germanylated, and stannylated ligands, and devices made with such compounds
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Page/Page column 8, (2008/06/13)
The present invention is directed to electroluminescent complexes of iridium(III) with silylated, germanylated and stannylated ligands. The invention is further directed to electronic devices in which the active layer includes an electroluminescent Ir(III
IMPROVED CATALYSTS FOR ALPHA-OLEFIN MANUFACTURE
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Page/Page column 19, (2010/11/27)
Iron, cobalt, chromium or vanadium complexes of 2,6- pyridjnedicarboxaldehydes diimines and 2,6-diacylpyridines diimines which are suitable for catalyzing the oligomerization of ethylene to α-olefins exhibit more prolonged catalytic activity and/or yields
Novel catalysts useful for catalyzing the coupling of arylhalides with arylboronic acids
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Page/Page column 3-4, (2008/06/13)
The present invention relates to a new method of cross-coupling aryl moieties comprising reacting an arylhalide with an arylboronic acid in the presence of a palladium compound and a compound comprising a di-alkylphosphine moiety.
PROCESS FOR PRODUCING TERTIARY PHOSPHINE HAVING BULKY HYDROCARBON GROUP BONDED
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Page 22, (2008/06/13)
The present invention provides a production process by which tertiary phosphine with an attached sterically bulky hydrocarbon group, said tertiary phosphine being useful as a ligand of a transition metal catalyst in organic synthesis reactions, can be produced in a high yield and with high purity on an industrial scale through simple and safe operations. The present invention comprises allowing a dialkylphosphinous halide to react with a Grignard reagent in the presence of a copper compound in an amount corresponding to 0.1 to 5% by mol based on the dialkylphosphinous halide to produce tertiary phosphine represented by the following formula (3) : wherein R1 and R2 are each a tertiary hydrocarbon group of 4 to 13 carbon atoms, and R3 is an alkyl group, an alkenyl group, an aryl group or the like.
CsOH-promoted P-alkylation: A convenient and highly efficient synthesis of tertiary phosphines
Honaker, Matthew T.,Sandefur, Benjamin J.,Hargett, James L.,McDaniel, Alicia L.,Salvatore, Ralph Nicholas
, p. 8373 - 7377 (2007/10/03)
A mild and efficient method for the synthesis of tertiary phosphines and ditertiary phosphines has been developed. In the presence of cesium hydroxide, molecular sieves and DMF at room temperature, various secondary phosphines and alkyl bromides were examined, and the results have demonstrated that this methodology offers a general synthetic procedure to produce tertiary phosphines in moderate to high yields. Optically active tertiary phosphine synthesis is also described.
