Methyl phosphite

Synonyms DMHP dimethoxyphosphine oxide dimethyl phosphite methyl phosphonate... 

SYNS BIS(HYDROXYMETHYL)PHOSPHINE OXIDE DIMETHOXYPHOSPHINE OXIDE DIMETHYL ACID PHOSPHITE DIMETHYLESTER KYSEUNY FOSFORITE (CZECH) DIMETHYLFOSFIT DIMETHYLFOSFONAT DLMETHYLHYDRO-GENPHOSPHITE DLMETHYL PHOSPHITE DIMETHYL PHOSPHONATE DIMETHYL PHOSPHOROUS ACID HYDROGEN DIMETHYL PHOSPHITE METHYL PHOSPHONATE NCI-C54773 PHOSPHOROUS ACID DIMETHYL ESTER... 

Tri-n-butyl phosphite-methyl copper, 441 Tri-n-butyltin hydride, 118, 424 Trichloramine, 424-425 Trichloroacetic acid, 372, 411, 425... 

HR=R the reaction appears to be catalytic, as a small quan-tity of iJ Cl will suffice to convert a considerable quantity of the phosphite into the alkylphosphonate (I). As little as O-Ol ml. of methyl iodide will isomerize trimethyl phosphite. Methyl iodide can be replaced satisfactorily by dimethyl sulphate. 

Alternative Names/Abbreviations Dimethoxyphosphine oxide, dimethyl phosphite, methyl phosphonate, DMHP... 

Dimethyl phosphorous acid DMHP Hydrogen dimethyl phosphite Methyl phosphonate Phosphonic acid, dimethyl ester Phosphorous acid, dimethyl ester... 

Methyl-3-phenyl-5-(3-trifluoromethylphenyl)-4-pyridone. See l-Methyl-O-phenyl-S-fO-ltrifluoromethyl) phenyl]-4(1H)-pyridinone Methyl phosphate. See trimethyl phosphate Methyl phosphite. See Trimethyl phosphite Methyl phosphonate. See Dimethyl hydrogen phosphite... 

Reaction of 3,4-bis(tri luoromethyl)-l,2-dithieten (64) with the phosphetan (65), methyl ethylene phosphite, methyl catechol phosphite, and trimethyl phosphite at low temperatures yields novel sulphur-containing phosphoranes e.g. (66) and (67) ], whereas triphenylphosphine gives only triphenylphosphine... 

When it comes to preparing oligomers, i.e., polymers of very low molecular weight, free-radical processes are usually not very useful. In triethyl phosphite, methyl methacrylate has been oligomerized using AIBN as initiator. The resultant product was said to have degrees of polymerization of between 1 and 3 when the ratio of triethyl phosphite to monomer exceeded 1. The oligomerization of acrylic or methacrylic acids in this solvent proceeded without the use of an initiator and were considered to be anionic polymerizations [60]. 

In addition to alcohols, some other nucleophiles such as amines and carbon nucleophiles can be used to trap the acylpalladium intermediates. The o-viny-lidene-/j-lactam 30 is prepared by the carbonylation of the 4-benzylamino-2-alkynyl methyl carbonate derivative 29[16]. The reaction proceeds using TMPP, a cyclic phosphite, as a ligand. When the amino group is protected as the p-toluenesulfonamide, the reaction proceeds in the presence of potassium carbonate, and the f>-alkynyl-/J-lactam 31 is obtained by the isomerization of the allenyl (vinylidene) group to the less strained alkyne. 

IS the only phosphorus isotope present at natural abundance and has a nuclear spin of The H NMR spectrum of tnmethyl phosphite (CH30)3P exhibits a doublet for the methyl protons with a splitting of 12 Hz... 

Cost bilizers. In most cases the alkyl tin stabilizets ate particularly efficient heat stabilizers for PVC without the addition of costabilizers. Many of the traditional coadditives, such as antioxidants, epoxy compounds, and phosphites, used with the mixed metal stabilizer systems, afford only minimal benefits when used with the alkyl tin mercaptides. Mercaptans are quite effective costabilizets for some of the alkyl tin mercaptides, particularly those based on mercaptoethyl ester technology (23). Combinations of mercaptan and alkyl tin mercaptide ate currendy the most efficient stabilizers for PVC extmsion processes. The level of tin metal in the stabilizer composition can be reduced by up to 50% while maintaining equivalent performance. Figure 2 shows the two-roU mill performance of some methyl tin stabilizers in a PVC pipe formulation as a function of the tin content and the mercaptide groups at 200°C. 

The aHphatic iodine derivatives are usually prepared by reaction of an alcohol with hydroiodic acid or phosphoms trHodide by reaction of iodine, an alcohol, and red phosphoms addition of iodine monochloride, monobromide, or iodine to an olefin replacement reaction by heating the chlorine or bromine compound with an alkaH iodide ia a suitable solvent and the reaction of triphenyl phosphite with methyl iodide and an alcohol. The aromatic iodine derivatives are prepared by reacting iodine and the aromatic system with oxidising agents such as nitric acid, filming sulfuric acid, or mercuric oxide. 

The raw precious metal concentrate is totally dissolved in hydrochloric acid—chlorine solution to form the soluble chloride ions of each of the metals. Silver remains as insoluble silver chloride and can be filtered off. Gold, in the form of [AuClJ, is extracted with, eg, tributyl phosphite or methyl isobutyl ketone. Base metals are also extracted in this step, and are removed from the organic phase by scmbbing with dilute hydrochloric acid (HCl). Iron powder is then used to reduce the gold species and recover them from the organic phase. 

Trimethyl phosphite P(OMe)3 spontaneously iso-merizes to methyl dimethylphosphonate MePO-(OMe)2, whereas other trialkyl phosphites undergo the Michaelis-Arbusov reaction with alkyl halides via a phosphonium intermediate ... 

On another occasion, upon addn of tri-methyl phosphite to anhyd Mg perchlorate, the mixt expld with injury to the operator (Ref 12a). Anhyd Mg perchlorate was added to a mixt of Bu acrylate and acrylonitrile, and the mixt polymerized in a 2.75 inch mold to give an illuminating flare of 2 miilion CP (Ref 14)... 

The following reaction sequence was used to obtain methyl hydroxymethanediphosphonic acid. This compound is widely used as a water hardness sequestering agent and detergent builder. Triethyl chloride was reacted with acetyl chloride to give diethylacetylphosphonate, followed by a conversion with diethyl phosphite and sodium. After completion of this reaction the substance was hydrolyzed with HC1 to yield hydroxymethanediphosphonic acid, [93,94], as shown in Eqs. (49)-(51) ... 

In the presence of strong alkali dialkyl phosphites can be added to unsaturated compounds. Thus salts of carboxyethyl- or dicarboxyethylphosphonic acid are obtained by addition of dialkyl phosphites to methyl acrylate [99] in the presence of sodium methylate in methanol. Diethylmaleate similarly gave diethyldiethylphosphonosuccinate [100], according to Eqs. (55) and (56) ... 

Another method for the preparation of hydroxyalkanephosphonic acids is the conversion of aldehydes with dialkyl phosphites in the presence of triethylamine or sodium methylate leading directly to the corresponding a-hydroxyalkane-phosphonates. This reaction is reversible, leading to the starting materials aldehyde and diethyl phosphite again [143,146]. 

Oleic acid, linolic acid, ricinolic acid, and 2-bromostearic acid methyl ester as well are reacting with diethyl phosphite in the presence of benzoyl peroxide to the corresponding phosphono fatty acid esters [156-158]. 

The 9,10-phosphonostearic acid in form of its sodium salt shows a good thermal stability and was efficient as an inhibitor in rust protection. The diethyl-phosphonoacetoxystearic acid methyl ester is used as additive in high-pressure lubricants. Rust protection properties are also shown by 9,10-phosphonostearyl alcohol [157]. Trisodium 9,10-phosphonostearate possesses the best surface activity in an 0.2% aqueous solution showing 33 mN/m at 30°C and a pH value of 10.5 [156]. By the addition of dialkyl phosphite to a,p-unsaturated ketones the y-oxophosphonic acids are available [159]. Addition of dialkyl phosphite to y-ketoacids leads to a-hydroxy-y-carboxyphosphonates see Eq. (86) ... 

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