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1.
X-Ray study of the (3,5-diallylisocyanuratomethyl)bis(chloromethyl)phosphine oxide showed that the phosphorylmethyl group is bonded to the nitrogen atom of the cycle. Reaction of the tris(chloromethyl)phosphine sulfide with sodium diallylisocyanurate gave (3,5-diallylisocyanuratomethyl)bis(chloromethyl)phosphine sulfide, and treatment of the tris(3,5-diallylisocyanuratomethyl)phosphine oxide with phosphorus pentasulfide gave a tris(3,5-diallylisocyanuratomethyl)bis(chloromethyl)phosphine sulfide.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 1446–1448, August, 1993.  相似文献   

2.
Rhodium-catalyzed hydroformylation of 1-octene in the presence of different phosphine and phosphine oxide ligands has been investigated. The molecular structure of new phosphine ligand, fluorenylidine methyl phenyl diphenylphosphine, was determined by single-crystal X-ray crystallography. Parameters such as different ligands, molar ratio of ligand to rhodium complex, ratio of olefin to rhodium complex, pressure of CO : H2 mixture, and time of the reaction were studied. The linear aldehyde was the main product when the phosphine ligands were used as auxiliary ligands while the selectivity was changed to the branched products when the related phosphine oxide ligands were used. Under optimized reaction conditions, in the presence of [Rh(acac)(CO)(Ph3P)]-di(1-naphthyl)phenyl phosphine oxide, conversion of 1-octene reached 97% with 87% selectivity of branched aldehyde.  相似文献   

3.
Phosphine (PH3) is a natural constituent in phosphorus (P) chemical cycles. The discovery of phosphine will shed new light on the mechanisms of P supplement and biogeochemical cycles. Since phosphine is converted to phosphate after complex oxidation via hypophosphite and phosphite, if it were present in the water column, understanding its production and emission could enhance our understanding of P speciation.

Assuming that phosphine in the gas phase is an ideal gas and at equilibrium between water and gas interface, phosphine in water solution can be quantified from the equilibrated concentration in gas phase using the Henry's Law. Application of this approach to Lake Taihu, China, phosphine in unfiltered and filtered water samples (0.45 μm) was analysed. Results showed that phosphine was universally present in Lake Taihu water. Phosphine concentration in unfiltered water ranged from 0.16 to 1.11 pg L?1, and was much less (0.01 to 0.04 pg L?1) in filtered samples. Over 90% of phosphine was adsorbed onto or incorporated into suspended materials with <10% dissolved in the water. Higher phosphine concentrations could be observed in warm seasons. Positive relationships were found between PH3 and TP (average R 2 = 0.59 ± 0.22) and TSP (average R 2 = 0.37 ± 0.13).  相似文献   

4.
A planar chiral secondary phosphine oxide based on [2.2]paracyclophane was synthesized and its chemistry investigated; it was shown to be a competent pre-ligand in palladium(0)-mediated reactions, and displayed promising activity in gold(I)-catalysed cyclisations. The secondary phosphine oxide could be transformed into a collection of P-stereogenic tertiary phosphine oxides. These are rare examples of the planar chirality of [2.2]paracyclophane being combined with a P-stereogenic centre. Unfortunately, epimerisation of the phosphorus stereocentre during reduction limits the use of this chemistry.  相似文献   

5.
The reactions of bis(anilino)phosphine oxide (C 6 H 5 NH) 2 P(O) H with (C 5 H 5 )2TiCl2 or Me2SiCl2 in a 1:1 molar ratio in THF results in the isolation of new phosph(V)azane complexes (C5H5)2Ti[(N C6H5)2P(O)H] (1) or Cl 2 Si[(N C 6 H 5 )2P(O)H] (2), respectively. In these reactions, HCl or CH4 elimination occurs and N-Ti or N-Si bonds form directly between a bis(anilino)phosphine oxide ligand and organotitanium or organosilicon compounds. The products(1) and (2) have been fully characterized by elemental analysis as well as 1 H, 31 P, 29 Si NMR, and IR spectroscopy.  相似文献   

6.
Preliminary results on the emission sources of atmospheric phosphine and the types of its precursors in the environment are described. Sunlight plays a more important role than oxygen in its degradation. The vertical profile of phosphine levels in ambient air has been measured. Laboratory simulation of phosphine formation under anaerobic conditions shows that addition of chicken manure, bone powder, or lecithin leads to an increment in phosphine emission. Phosphine can also be adsorbed to soil matrix and thus can survive in soil and sediment. Adsorption and light degradation explain the low ambient levels of phosphine.  相似文献   

7.
Photolysis of [Me2SiSiMe2)[C5H4Fe(CO2)]2with a series of bis(phosphine)ligands Ph2P(CH2)n PPh2(n=1-4) leads to the formation of the corresponding diiron complexes with intramolecular and intermolecular bis(phosphine) substitution.When these complexes were heated in refluxing xylene.only in the complexes with intermolecular bis(phosphine )substitution the thermal rearrangement reaction occurred.  相似文献   

8.
The kinetics and mechanism of photodehydrogenation of the phosphine hydride complexes MH4L4 (M = Mo, W; L are phosphine ligands) and the formation of coordinatively unsaturated species ML4 were studied by the absorbance of long-wavelength bands with λmax at 450–460 nm appeared in the absorption spectra of the photoproducts. The rate constants of the reactions of the coordinatively unsaturated M(DPPE)2 species (M = Mo, W; DPPE = Ph2PCH2CH2PPh2) with molecular nitrogen in benzene were determined (k W = 200 s−1, k Mo = 8700 s−1). Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 282–284, February, 2008.  相似文献   

9.
Three Ru–η6‐benzene–phosphine complexes bearing tri‐(p‐methoxyphenyl)phosphine, triphenylphosphine and tri‐(p‐trifluoromethylphenyl)phosphine were synthesized and characterized by 31P{1H} NMR, 1H NMR, 13C{1H} NMR and elemental analyses. Complex 1 was further identified by X‐ray crystallography. These complexes exhibit good to excellent activities for the transfer hydrogenation of ketones in refluxing 2‐propanol, and the highest turnover frequency (TOF) is up to 5940 h−1. The effect of electronic factors of these complexes on the transfer hydrogenation of ketones reveals that the catalytic activity is promoted by electron‐donating phosphine and the catalyst stability is improved by electron‐withdrawing phosphine. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

10.
Extraction behavior of some selected actinides like U(VI), Th(IV), and Am(III) was investigated with three different H-phosphine oxides, viz. diphenyl hydrogen phosphine oxide (DPhPO), dihexyl hydrogen phosphine oxide (DHePO) and diphenyl phosphite (DPP). The H-phosphine oxides exhibited a dual nature towards the extraction of actinides where the ligand not only extracts the metals by cation exchange but also by coordination with the phosphoryl group at lower and higher acidic concentrations, respectively. Among all ligands employed, DPhPO showed highest extraction with actinides with a substituent dependent trend as follows: DPhPO > DHePO > DPP. This trend emphasizes the importance of substituents around the phosphine oxide towards their extraction of actinides. The coordination behavior of DPhPO was studied by investigating its corresponding complexes with Th(NO3)4 and UO2(NO3)2. The metal complexes of these actinides were characterized using FT-IR, 1H and 31P NMR spectroscopic techniques. Density Functional Theory (DFT) calculations were also performed to understand the electronic and geometric structure of the ligand and the corresponding metal complexes.  相似文献   

11.
The catalytic activities of three N‐methylimidazole‐based phosphine ligands in the Suzuki coupling reaction were tested using PdCl2 as the catalyst. The results showed all three phosphine ligands exhibited excellent activity towards the Suzuki reaction, and the catalytic activity decreased with increasing number of imidazole groups. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

12.
Reaction of sodium diallylisocyanurate with tris(chloromethyl)-, bis(chloromethyl)phenyl-, and (chloromethyl)diphenylphosphine oxides yields, depending on the stoichiometric ratio of the reagents, mono-, bis-, and tris(3,5-diallylisocyanuratomethyl)phosphine oxides.A. E. Arbuzov Institute of Organic and Physical Chemistry, Kazan Science Center, Russian Academy of Sciences, 420083 Kazan, Tatarstan, Russia. Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 12, pp. 2773–2777, December, 1992.  相似文献   

13.
Chin-Pei Chang 《Tetrahedron》2005,61(15):3835-3839
Biphasic Suzuki-coupling reactions of aryl and benzyl bromides employing a cobalt-containing phosphine ligand chelated palladium complex 2 were carried out in various reaction conditions. Comparisons of the catalytic efficiencies in the presence/absence of a phase-transfer agent, TBAB, were presented. In addition, the effects of altering solvents, temperatures, catalysts, and substrates on the reactions were monitored and reported. Better yields were commonly observed while a phase-transfer agent TBAB was participated in the reactions. The factor of reaction time is more crucial than that of temperature in short reaction hour experiments. Obviously, an induction period for the reduction of Pd(II) to Pd(0) active species is needed for this type of reaction.  相似文献   

14.
Substitution reactions of phosphine ligands, triphenylphosphine (PPh3), tri(m-chlorophenyl)phosphine (m-ClPPh3), tri(p-methoxyphenyl)phosphine (p-MeOPPh3) and tri(benzyl)phosphine (PBz3) with [M(CO)4(PCA)] (M?=?Cr, Mo and W, PCA?=?pyrazinecarboxamide) were found to be dependent on the type of metal and phosphine ligand. The complexes were characterized by elemental analysis, mass spectrometry, and IR and 1H NMR spectroscopy. UV–vis spectra of the complexes in different solvents showed bands due to metal-to-ligand charge transfer.  相似文献   

15.
The reactions of dimeric complex [Rh(CO)2Cl]2 with hemilabile ether‐phosphine ligands Ph2P(CH2) nOR [n = 1, R = CH3 (a); n = 2, R = C2H5 (b)] yield cis‐[Rh(CO)2Cl(P ~ O)] (1) [P ~ O = η 1‐(P) coordinated]. Halide abstraction reactions of 1 with AgClO4 produce cis‐[Rh(CO)2(P ∩ O)]ClO4 (2) [P ∩ O = η 2‐(P,O)chelated]. Oxidative addition reactions of 1 with CH3I and I2 give rhodium(III) complexes [Rh(CO)(COCH3)ClI(P ∩ O)] (3) and [Rh(CO)ClI2(P ∩ O)] (4) respectively. The complexes have been characterized by elemental analyses, IR, 1H, 13C and 31P NMR spectroscopy. The catalytic activity of 1 for carbonylation of methanol is higher than that of the well‐known [Rh(CO)2I2]? species. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

16.
选择适当的反应条件实现对环境无害的有机及催化反应是 2 1世纪化学家所面临的重要挑战 [1~ 3 ] .Kuntz研究组 1 975年开展民含水两相催化反应的研究 [4 ] ,水溶性膦配体与过渡金属 (如铑、钯和镍等 )所形成的配合物可在水 /有机两相催化体系中实现不对称氢化、烯丙型烷基化、  相似文献   

17.
This article describes efficient preparation of isomeric allyl phosphine oxides possessing a protected cyclohexanediol fragment. Their base-catalyzed interconversions are examined and reactions with the Grundmann ketone provide an adduct containing the rearranged vinyl phosphine oxide moiety, instead of 19-norvitamin D3 analogs, the expected products of the Horner–Wittig process.  相似文献   

18.
The possibility of activation of the C-H bond by dinuclear phosphine bridged complexes of rhodium, iridium, and ruthenium is considered.This work was reported at the conference Modern Problems of Organometallic Chemistry (8–13 May, 1994, Moscow).Institut fer Technische Chemie und Petrolchemie der RWTH Aachen Worringerweg 1, 52074 Aachen, Deutschland.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 589–593, April, 1994.  相似文献   

19.
Spectrophotometric method for the determination of phosphine (PH3) residues in coriander has been developed based on the reaction of phosphine with silver nitrate in 2% aqueous isopropanol. The yellow chromophore formed has an absorption maximum at 430 nm and the linear relation between the absorbances at 430 nm and the concentration of PH3 is obeyed in the range of 0.02 to 0.17 g. The method is sensitive with a detection limit of 0.008 g and can be applied for determination of 0.02 g/g residue in coriander. Recovery of added PH3 from a closed system ranges from 96 to 101%.  相似文献   

20.
Ultra-branched mixed tetradentate tripodal phosphines and phosphine chalcogenides have been synthesized by the exhaustive regioselective addition of secondary phosphines, phosphine sulfides and phosphine selenides to available tris(4-vinylbenzyl)phosphine oxide under free-radical conditions (UV irradiation or AIBN) in good to excellent yields.  相似文献   

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