Phenyl Phosphite Research Articles

Investigations of the Determination of Phosphorus in Organic Media by Atomic Absorption Heated Graphite Atomizer

The analysis of phosphorus in organic compounds used as product additives has been investigated. It has been found necessary to change the organic phosphorus to inorganic phosphorus before measuring it by atomic absorption spectrophotometry. In the determination of tricresyl phosphate in gasoline the gasoline is ashed on magnesium sulfonate. The tricresyl phosphate is converted to Mg2P2O7 and subsequently dissolved in nitric acid, diluted to desired concentration, and then injected into the heated graphite furnace. A calibration curve is made from gasoline containing a known phosphorus content to give a range of 1 to 10 ppm. Twenty-five microliters of the knowns and unknown are injected on 10 µl of a 1% solution of lanthanum nitrate on the graphite tube. An alkyl phenyl phosphite additive is diluted in dimethylformamide to bring it into solution in the range of 1 to 10 ppm phosphorus. A portion is ashed on magnesium oxide with the addition of 1 ml of 30% hydrogen peroxide. The Mg2P2O7 is dissolved in nitric acid, then diluted to the calibration curve range. It is injected into the heated graphite furnace in the presence of 10 µl of a 1% lanthanum nitrate solution.

Polymerization via zwitterions. 22. Alternating copolymerization of 2-acryloxypropionic acid with cyclic phosphorus compounds

Alternating copolymerization of 2-acryloxypropionic acid (APA) as a new MN with two MN monomers of phosphorus containing ethylene phenyl phosphonite (EPO) and ethylene phenyl phosphite (EPI) have been disclosed. Copolymerizations took place without added catalyst to produce 1∶1 alternating copolymers of APA-EPO and of APA-EPI. The structures of the copolymers were determined by IR and NMR spectroscopy, elemental analyses, as well as the identification of the alkaline hydrolysis products. The copolymerizations were explained in terms of a mechanism of zwitterion intermediates involving a hydrogen transfer process.

Double Ring‐Closure Additions to o‐(Methyleneamino)‐phenyl Phosphites

Double Ring‐Closure Additions to <i>o</i>‐(Methyleneamino)‐phenyl Phosphites

ChemInform Abstract: REACTIONS OF DIMETHYLMETHYLTHIOSULFONIUM FLUOROBORATE WITH SOME NUCLEOPHILES

AbstractMit Triphenylphosphit (II) erhält man aus (I) über (III) und (IV) das Thiophosphat (V) und das Trimethylsulfonium‐Salz (VI).

REACTIONS OF DIMETHYLMETHYLTHIOSULFONIUM FLUOROBORATE WITH SOME NUCLEOPHILES

Abstract Reactions of dimethylmethylthiosulfonium fluoroborate with phenyl phosphite, pyridine, 4-cyanopyridine, N,N-dimethylaniline, p-nitro-N,N-dimethylaniline, thiophenol or sodium thiophenolate are almost instantaneous at room temperature, while the reactions with phenols and anisole proceed slowly at 60°C. Products are determined, and the mechanisms are discussed.

Metal salt-catalysed carbenoids. Part IX. The catalysts in trialkyl phosphite–copper(I) complex catalysed decomposition of diazomalonic esters in cycloalkenes

Partial rate data, asymmetric induction studies, interrupted experiments, and additives studies indicate that copper(I) salt–phosphite complexes are destroyed during the course of reactions with dimethyl diazomalonate (1) and ethyl diazoacetate (2). All evidence is consistent with the copper(I) being oxidized to copper(II) and copper(0) being oxidized by impurities in the olefin which most probably are hydroperoxides.Several new copper(I) salt–phosphite complexes have been prepared and examined but none proved as effective for decomposing compound (I) as bis(acetylacetonato)copper(II).The utility of the chloro(trimethyl phosphite)copper(I) for decomposing compound (I) is a function of the means of preparation. The three general methods employed furnished samples having superposable i.r. spectra and superposable proton n.m.r. spectra but exhibited varying degrees of line broadening in the 31P n.m.r.The chiral mixed phosphite ligand bornane-2,3-diyl phenyl phosphite (3) derived from bornane-2,3-diol failed to induce any asymmetric induction in the reaction between (2) and styrene when complexed with copper(I) iodide even though the ligand is chiral at four carbons and phosphorus.

Spectral study of complexes of dialkyl(aryl) phosphites and trialkyl(phenyl) phosphates with phenol

The enthalpy for the formation of the complexes of phenol with dialkyl(phenyl) phosphites and trialkyl(phenyl) phosphates is determined both by the induction effect of the substituents and by their resonance interaction with the phosphoryl group, which is the same within the limits of each of the indicated series.

Solvent extraction of salts by organic phosphites—II: Extraction of cuprous chloride

The extraction of cuprous chloride by a series of alkyl, aryl and mixed alkyl-aryl tertiary phosphites (S) is described, complexes of the types CuCl . S and CuCl . 2S being formed. The high specificity of these phosphites for copper (I) relative to other common metals is discussed. Effects of chloride ion and of time on copper extraction are illustrated, and first order reaction rate constants varying from 0·021 to 0·83 min −1 are ascribed to primary salt effects in the range 0·10-1·5 M sodium chloride. Hydrolysis of the tertiary di-2 ethylhexyl phenyl phosphite to the secondary mono-2 ethylhexyl phenyl phosphite has been studied under low acid conditions and a first order reaction rate constant of 6·5 × 10 −3 min −1 obtained. Formation of a copper complex with tertiary phosphites, in acid solution, completely protects them from hydrolysis. Under alkaline conditions, hydrolysis of phosphites is extremely slow.

The reaction of phosphites with sulphoxides

In reactions between phosphites and sulphoxides, the basicity of the phosphorus atom in phosphites appears to play an important role in determining the reaction process. Triphenyl phosphite and diphenyl methyl phosphite were oxidized quantitatively to the corresponding phosphates by treating with phenyl methyl sulphoxide, while trimethyl phosphite was found to rearrange to dimethyl methylphosphonate by the catalytic action of sulphoxides. Similarly, triethyl phosphite was found to rearrange to diethyl ethylphosphonate. Dimethyl phenyl phosphite gave a mixture of dimethyl phenyl phosphate and a phenyl methyl methylphosphonate in the reaction with phenyl methyl sulphoxide.

Effect of the size and structure of radicals present in phosphorus esters on the rate of isomerization of these substances

1. Some new dialkyl phenyl and alkyl diphenyl phosphites have been synthesized. 2. In the series of alkyl diphenyl phosphites, only the methyl and ethyl esters isomerize smoothly. The higher homologs decompose when they react with the corresponding alkyl iodides. 3. A number of new addition products of alkyl iodides with triphenyl phosphite has been prepared. 4. The products of the addition of methyl, ethyl, and n-butyl iodides to triphenyl phosphite decompose at 210–220° according to the scheme of the second stage of the Arbuzov rearrangement. 5. By the action of alcohol on the products of the addition of benzyl, isopropyl, n-butyl, and isobutyl iodides to tripbenyl phosphite, the diphenyl esters of the corresponding alkylphosphonic acids have been prepared, these reactions confirm the structures of the addition products. 6. The above facts (3,4, and 5) show that the Arbuzov rearrangement occurs in two stages with the formation of an intermediate addition product. 7. It has been shown that the isomerization products of phosphorous esters are substances that accelerate the isomerization process. The isomerization reaction is therefore autocatalytic. 8. Isobutyl iodide adds to triphenyl phosphite considerably more rapidly than n-butyl iodide does. The addition reaction of isobutyl iodide, unlike those of the other alkyl iodides examined, has a long induction period.