Ethyl -7/-phosphinate

The energies of protonation of the complete series of methyl and ethyl phosphines have been calculated. pATa values for the hydroxyphenyl-... 

Stereochemistry. - There has been a far infra-red spectroscopic study of ethyl phosphine,130 and in combination with X-ray fluorescence, further work completed on the conformational analysis of dialkylphenyl phosphines.131 The influence of water on the conformational equilibria of trimethyl phosphate has received attention.132 There has been a low temperature solid state and matrix isolation study of methyl phosphorodichi oridate,133 and a conformational study of polymorphic modifications of diphenyl-phosphinyl acetic acid hydrazide. 34... 

The first examples of five-coordinate platinum(II) complexes of the type [Pt(PR3)L]2+ (L = tris(2-(diphenylphosphino)ethyl)phosphine R = Et, OMe, OEt) (104) containing only P-donor atoms have been prepared by the reaction of [PtClL]+ with an appropriate monodentate tertiary phosphine or phosphite ligand.284 Triaryl phosphines and phosphites do not react with the precursor complex, even at elevated temperatures, most probably due to the considerable steric interactions that would occur upon the approach of the P-donor ligand to the platinum(II) center. 

The 31P NMR spectra of 28-30 showed signals characteristic of their structural features. Dimeric species 28 with l,l,l-tri(diphenylphosphinomethyl)ethane affords two singlets at 23.0 and —28.6 ppm due to the coordinated and nonco-ordinated P donors, respectively. For trimeric species 29, two singlets occur at 24.3 and 14.4 ppm, ascribed to two classes of P donors in bis[2-(diphenylphos-phino)ethyl]phenylphosphine. Because of two types of P donors in tri[2-(diphenylphosphino)ethyl]phosphine, tetrameric species 30 exhibits two singlets at 16.4 and 24.0 ppm. 

A Michael-type addition reaction of phosphine generated from red phosphorus in concentrated aqueous KOH solution has been noted to provide moderate isolable yields of pure organophosphorus products.27 For example, tris-(2-cyanoethyl)phosphine is produced in 45% isolable yield from acrylonitrile, and tris-(2-[y-pyridyl]ethyl) phosphine oxide is isolated in 40% yield from 4-vinylpyridine under these conditions. Excellent yields of the tertiary phosphine oxide, tris-(2-cyanoethyl)phosphine oxide, have been reported using white phosphorus in absolute ethanol with KOH at ice/salt-bath temperatures.28 A variety of solvent systems were examined for this reaction involving a Michael-type addition to acrylonitrile. Similarly, tris-(Z-styryl)phosphine is produced from phenylacetylene under these conditions in 55% isolated yield. It is noteworthy that this last cited reaction involves stereospecific syn- addition of the phosphine to the alkyne. 

Maier, L., The addition of hypophosphite esters to activated olefins, a new method for preparing substituted ethyl phosphinates, Helv. Chim. Acta, 56, 489, 1973. 

Miscellaneous spectral studies include e.s.r. spectra of chloro-phosphines (2)6 and vibrational spectra of various phosphines.6-8 N.m.r. studies include those of borane complexes of aryldichlorophosphines,9 and studies of the conformation of dichloro-(isopropyl)phosphine (3)10 and dichloro(ethyl)phosphine (4).10 These phosphines have the preferred conformations shown. Conformation has also been the theme of electron-diffraction work on the anhydride (5), which appears to have a staggered conformation.11 The electronic implications of a relatively short P—O bond and wide POP angle have been discussed.11... 

By the use of base catalysts phosphine and phenylphosphine for example can be cyanoethylated. Acrylonitrile and phosphine react together at room temperature in the presence of aqueous potassium hydroxide solution to give, depending on the reaction conditions, primary, secondary and tertiary 2-cyano-ethyl-phosphines... 

According to E. Drechsel and E. Finkelstein, when a current of dry phosphine is passed into a soln. of zinc ethide in absolute ether, which must be cooled by a mixture of ice and salt, the separation of a white pulverulent precipitate is observed, which gradually increases in quantity. The precipitate was collected on a filter, washed rapidly with absolute ether, and dried in vacuo over sulphuric acid. The body thus obtained continually exhales phosphine when exposed to the air its analysis corresponds with zinc hydrophosphide. The zinc hydrophosphide is decomposed at once by cold water, with evolution of phosphine and formation of zinc hydroxide. It is especially interesting for the ease with which it is attacked by chlorides and iodides acetyl chloride acts upon it energetically, but the product of the reaction has not been thoroughly examined. By heating together the zinc hydrophosphide, ethyl iodide, and ether to 150°, ethyl-phosphine was produced. 

A convenient route to trivinylphosphine has been developed by thiol elimination from tris[2-(phenylthio)ethyl]phosphine oxide.56 The reaction mechanism involves a phosphoryl-stabilized carbanion, from which benzene thiolate anion is eliminated. 

MRH Phosphine 2.13/11, phosphorus trioxide 0.46/43, magnesium phosphide 4.02/39 Borondiiodophosphide, phosphine, phosphorus trioxide and trimercury tetraphos-phide all ignite in contact with chlorine at ambient temperature. Trimagnesium diphosphide and trimanganese diphosphide ignite in warm chlorine [1], while ethyl-phosphine explodes with chlorine [2]. Unheated boron phosphide incandesces in chlorine. 

It has been shown that coupling of the ethyl phosphinate A with 5 -azido-2 -methoxy-5 -deoxythymidine B to afford the corresponding phosphon-amidate proceeds with retention of configuration at the phosphorus atom. Determine the configuration of reactants and product. 

CLOROFOS (RUSSIAN) COMBOT EQUINE DANEX DEP (pesticide) DEPTHON DETF DI-METHOXY-2,2,2-TRICHLORO-l-HYDROXY-ETHYL-PHOSPHINE OXIDE 0,0-DLMETHYL-(l-HYDROXY-... 

DIMETHOXYTETRAGLYCOL see PB0500 DIMETH0XY-2,2,2-TRICHL0R0-1-HYDR0XY-ETHYL-PHOSPHINE oxide see TIQ250... 

Physiologically, homocysteine exists in reduced, oxidized, and protein-bound forms.Methods for tHcy were first introduced in the midl980s that resolved the problems related to the presence of multiple unstable Hey species in plasma by converting all Hey species into the reduced form, HcyH, which is measured as an indication of tHcy content. Consequently, modern methods require pretreatment of plasma or serum specimens with a reducing agent, such as dithioerythritol, dithiothreitol, mercap-toethanol, tributyl phosphine, and tris(2-carboxyl-ethyl) phosphine that converts all Hey species into the reduced form, HcyH, which is measured as an indication of tHcy content. 

A study of the shifts produced by europium and praseodymium reagents on a series of ethoxy and ethyl phosphinous and phosphoryl compounds showed that the phosphorus shifts of the phosphines and phosphoryl compounds differed from the proton and carbon shifts in that they were dominated by contact interactions. Large pseudocontact phosphorus shifts for triethyl phosphite indicate that there is little direct P - La interaction. Shift reagents have been used in the stereochemical assignments of some bicyclic oxides such as (57) and the conformational analysis of dioxaphosphorinans (58) and dithiaphosphorinans (59). The conformational... 

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