Trimethylphosphine oxide

Cobalt, dinitratobis(trimethylphosphine oxide)-angular parameters, 1,57 structure, 1, 57... 

Depolarization data on trimethylphosphine oxide are now available and the relationship between the symmetric and asymmetric POP vibrations has been equated for diphosphates, and some halogen and metal salt derivatives. The polarization of a carbonyl group produced by its conjugation with an ylide causes a large decrease in vco- This shift to lower frequency is increased further when a double bond is interposed, thus increasing the extent of conjugation. -... 

Diisopropyl methylphosphonate is an organophosphate compound that was first produced in the United States as a by-product of the manufacture of the nerve gas isopropyl methylphosphonofluoridate (GB, or Sarin) (ATSDR 1996 EPA 1989 Robson 1977, 1981). It is not a nerve gas and is not a metabolite or degradation product (Roberts et al. 1995). Diisopropyl methylphosphonate constitutes approximately 2-3% of the crude GB product, but it is neither a metabolite nor a degradation product of GB (EPA 1989 Rosenblatt et al. 1975b). Diisopropyl methylphosphonate is not normally produced except for its use in research. One method of producing diisopropyl methylphosphonate is to combine triisopropyl phosphite and methyl iodide. The mixture is then boiled, refluxed, and distilled, yielding diisopropyl methylphosphonate and isopropyl iodide (Ford-Moore and Perry 1951). Diisopropyl methylphosphonate may also be prepared from sodium isopropyl methylphosphonate by a reaction at 270° C, but a portion of the resulting diisopropyl methylphosphonate is converted to trimethylphosphine oxide at this temperature (EPA 1989). 

A bis(secondary/tertiary) ligand reacted with diphenylzinc to afford the bis(phenylzinc) complex 88 (Scheme 67).148 The unusual reactivity of this dinuclear species was demonstrated by its interactions with trimethylphosphine oxide and iV,A-dimethylacetamide. In both cases, the products contained eight-membered rings incorporating both zinc atoms the structure of the bis(trimethylphosphine oxide) product is shown in Figure 46. 

Trimethyl- 1,3-pentanediol 2.2.4- Trimethyl-3-pentanone 2.4.4- Trimethyl- 1-pentene 2.4.4- Trimethyl-2-pentene Trimethylphosphine Trimethylphosphine oxide Trimethyl phosphate 2,3,6-Trimethylpyridine 8.6... 

Electron.—The determination of the molecular structure of phosphorus heterocycles by electron diffraction has been reviewed.176 The structures of trimethylphosphine oxide, and the corresponding sulphide in the gaseous phase, have been compared. The rotational freedom of the methyl group appears to be greater for the sulphide, which also has the longer P—C bonds, i.e. 181.8 pm for (144 Ch = S)and 180.9 pm for (144 Ch = O).177 The trifluoromethylphosphoranes (145) and (146) adopt the... 

Permittivity measurements have been used to study hydrogen bonding of phenol or carboxylic acids with trialkylphosphine oxides (154). The results can be explained in terms of a simple electrostatic model. The properties of trimethylphosphine oxide were different from the general properties of the series.189... 

Chen and coworkers employed trimethylphosphine oxide (TMPO) as the probe molecule to characterize pure and sulfated zirconia both with and without a metal promoter [210]. On pure Zr02 resonances were detected at 62, 53, 41 and 34ppm. 

The electron distribution in PCI5 has been studied by ab initio calculations, and the radical cation of trimethylphosphine oxide, Me3P -0, has also been examined. ... 

The crystal and molecular structure of tetrachlorobis(triphenylphosphine oxide) uranium(vi) has been determined from three-dimensional AT-ray diffraction data. The complex was found to adopt a distorted octahedral configuration with the neutral ligands co-ordinated in the cis positions. The single-crystal study of chlorohexakis-(trimethylphosphine oxide)uranium(iv) trichloride showed the uranium atom to be co-ordinated to one chlorine and six oxygen atoms. The co-ordination polyhedron was described in terms of a distorted monocapped trigonal antiprism or a distorted monocapped octahedron. 

ButCN, pyridine, or trimethylphosphine oxide (13). The inability to isolate coordination complexes with a variety of Lewis bases is rather surprising since uranium (III) is larger... 

Carbamates are one of the most widely used protecting groups for amines and the development of one-pot conversions of azides to carbamates such as Boc, Cbz, and allyl further expanded the scope of utility of the Staudinger reduction. Treatment of the Staudinger reaction iminophosphorane intermediate 26 with 1.05 equivalents of 2-t-(butoxycarbonyloximino)-2-phenylacetonitrile (Boc-on) led to Boc-protected amines 28 thru 32 in 87-100% overall yield.19 This process utilizes trimethylphosphine, which is more reactive than triphenylphosphine and provides an easier work-up because trimethylphosphine oxide is water soluble. It should be noted that the use of di-f-butyldicarbonate (B0C2O) has been investigated but leads to lower yields in comparison.20... 

Trimethylphosphine oxide, (CH3)gPO, may be obtained by several methods (1) Trimethylphosphine is oxidised in air, tliis... 

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