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Phosphinates alkylphosphinates

The unsaturated character of these trialkyl esters was shown by the ease with which they were attacked by nitric acid, but still more clearly by the formation, with evolution of heat, of stable crystalline addition compounds when they were mixed with cuprous halides. Thus CuC1.P(OC2H5)3 was described as consisting of colourless crystals melting at 190° to 192° C. and soluble in organic solvents.4 This property they share with phosphine, alkylphosphines and phosphorus trihalides. The phosphoric esters were quite indifferent to cuprous halides. Nor were such addition compounds formed either by phosphorous acid itself or by the dialkyl esters, which may show that the latter compounds have the unsymmetrical formula. Phosphorous acid probably exists in both forms, but first as P(OH)3, i.e. when produced from PC13 and Ha0.5 This may be transformed into the unsym-metrieal form through an addition compound HC1.P(0H)3,4 and probably also exists in the form of complex molecules, such as... [Pg.146]

Organophosphorus compounds. Phosphorus-carbon bond fonnation takes place by the reaction of various phosphorus compounds containing a P—H bond with halides or tritlates. Alkylaryl- or alkenylalkylphosphinates are prepared from alkylphosphinate[638]. The optically active isopropyl alkenyl-methylphosphinate 778 is prepared from isopropyl methylphosphinate with retention[639]. The monoaryl and symmetrical and asymmetric diarylphosphi-nates 780, 781, and 782 are prepared by the reaction of the unstable methyl phosphinate 779 with different amounts of aryl iodides. Tnmethyl orthoformate is added to stabilize the methyl phosphinate[640]. [Pg.243]

Other typical alkylphosphines that can be prepared through phosphine chemistry are monoisobutylphosphine [4023-52-3] trioctylphosphine [4731-53-7] monocyclohexylphosphiue [822-68-4] dicyclohexylphosphiue [829-84-5] and triethylphosphiue [554-70-1]. [Pg.319]

A mixture of (C H ) , TiCl, and AlCl is useful for polymerizing C —olefins (85). The dimerization of propylene is accompHshed by using catalysts such as Ni(PR2)4 (86). Alkylphosphines such as / fZ-butylphosphine [2501-94-2] have been proposed as a substitute for high purity phosphine in the production of the semiconductor gallium phosphide (87). [Pg.380]

Several t-alkylphosphines have been oxidized by aqueous alkali, resulting in the evolution of hydrogen gas. The only requirement for reduction appears to be the solubility of the phosphine in aqueous alkali... [Pg.14]

Sterically demanding, water-soluble alkylphosphines 6.10 and 6.11 as ligands have been found to have a high activity for the Suzuki coupling of aryl bromides in aqueous solvents (Eq. 6.35).115 Turnover numbers up to 734,000 mmol/mmol Pd have been achieved under such conditions. Glucosamine-based phosphines were found to be efficient ligands for Suzuki cross-coupling reactions in water.116... [Pg.189]

Contact with oxygen at 25°C/0.5 bar causes ignition of the phosphine. See related alkylphosphines... [Pg.390]

The reactions used for synthesis of II-VI (CdSe, CdTe), III-V (InP, InAs), and IV-VI (PbS, PbSe, PbTe) semiconductor nanocrystals are outlined by Schemes 3-5.4,17,30-32 The syntheses are carried out at high temperatures, and in the presence of long-chain alkylphosphines (trioctylphosphine,TOP), alkyl-phosphine oxides (trioctylphosphine oxide, TOPO), alkylamines (hexadecyl-amine, HD A), and alkylphosphonic acids as the stabilizing agents. [Pg.316]

The fluorous alkylphosphines 2 [8, 12] and 3 [8, 13], containing one or two perfluoroalkyl tails, respectively, have also been prepared. Partition coefficients of the chiral fluorous monophosphines 3a-b were found to be lower than the values measured for the corresponding phosphines 1, which contain one extra perfluoroalkyl tail [13], In addition, fluorous phosphinites, phosphonites and phosphites 4a-e and diphosphonite 5 have become available [8, 14]. [Pg.1379]

X-Ray data have been published for A -phospholen 1-oxide (65),69 tri-o-tolyl-phosphine derivatives (66),60 and various halogeno-alkylphosphine oxides.61... [Pg.82]

ALKYLHALOPHOSPHINES, ALKYLPHOSPHINES tert-BUTYL PEROXOPHOSPHATE ESTERS iV-CHLORINATED PHOSPHORUS AMIDES HALOPHOSPHINES, METAL PHOSPHINATES METAL PHOSPHORUS TRISULFIDES NON-METAL OXIDES, NON-METAL SULFIDES PHOSPHINES, PHOSPHORUS ESTERS... [Pg.337]

There are a few exceptions amongst the cationic complexes that also undergo oxidative addition of dihydrogen prior to alkene complexation. Alkylphosphines, raising the electron density on the rhodium cation, have been shown to belong to these exceptions, which seems logical [16] electron-rich phosphine complexes can undergo oxidative addition of H2 before the alkene coordinates to the rhodium metal. [Pg.86]

Since Shell s report on the use of phosphines in the cobalt catalysed process, which included preliminary data for the use of rhodium as well [1], many industries started to apply phosphine ligands in rhodium catalysed processes [2], While alkylphosphines are the ligands of choice for cobalt, they lead to slow reactions when applied in rhodium catalysis. In the mid-sixties the work of Wilkinson showed that arylphosphines should be used for rhodium and that even at mild conditions active catalysts can be obtained [3], The publications were soon followed by those of Pruett, in which phosphites were introduced (Figure 8.1) [4],... [Pg.139]

Palladium-catalyzed a-arylation of ketones is performed with arylene dihalides and bifunctional aromatic ketones 148 to result in the bond formation at the r/) -a-carbon of the ketone, leading to polyketone 149. The reaction is carried out in the presence of Pd(0) and various phosphines. Several bidentate phosphines and bulky alkylphosphines such as dppf, BINAP, PCys, and P Bu3 are shown to be effective, while PPh3 results in no reaction. Arylene dibromide and diiodide are applicable as the co-monomers. The polymerization reaction is carried out in THE in the presence of NaO Bu at 75 °C under N2, and polymers 149 are isolated in 60-80% yields (M = 7000-15 000). Polyketone 149 is further transformed to conjugated polymer PPV by reduction of the ketone moiety with LiAlH4 followed by dehydration with an acid (Equation (69)). [Pg.677]

Triphenyl phosphine is an example of a gel modification additive that acts to retard the rate of reaction, when the catalyst has tricyclo-alkylphosphine ligands. The catalyst with tricycloalkylphosphines ligands is much more active in ROMP than when the ligands would be triphenyl phosphines. [Pg.14]

For platinum(II) complexes with alkylphosphine ligands there is a small but marked dependence of the values (PC) on the nature of the group tram to phosphine.1353 By analogy with the earlier method using 3H NMR, 13C 1H NMR techniques using virtual coupling have been used for phosphite complexes of platinum(II), but it does not appear that the method can be generally used to determine stereochemistry.1354... [Pg.449]

The reactions were carried out by using trans-chloro( 1-naphthyl)-bis(triphenylphosphine)nickel(II) (l, Ar = Ci0H7) complex as catalyst in the presence of various phosphorus ligands. We observed that aromatic phosphines in arylnickel(II) complexes 1 are easily replaced by aliphatic phosphines. In fact in the presence of alkylphosphines, such as P( C6Hn )3 and P(C4H9)3, cyanation did not occur. Moreover phosphites such as... [Pg.271]


See other pages where Phosphinates alkylphosphinates is mentioned: [Pg.4]    [Pg.198]    [Pg.380]    [Pg.177]    [Pg.297]    [Pg.383]    [Pg.1378]    [Pg.369]    [Pg.218]    [Pg.135]    [Pg.122]    [Pg.163]    [Pg.722]    [Pg.9]    [Pg.106]    [Pg.528]    [Pg.111]    [Pg.837]    [Pg.375]    [Pg.492]    [Pg.517]    [Pg.474]    [Pg.389]    [Pg.992]    [Pg.992]    [Pg.665]    [Pg.409]    [Pg.251]    [Pg.9]   
See also in sourсe #XX -- [ Pg.285 ]




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Alkylphosphinates

Phosphine oxides alkylphosphine

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