Phenylphosphonic acid

Phenylphosphinic anhydride (129) decomposes on heating to give phenylphosphine, phenylphosphonic acid (130), and pentaphenylcyclo-pentaphosphine. Phenylphosphinidene (PhP = ) has been shown to be an intermediate in this decomposition, by trapping with benzil to give the adduct (131) in very low yield. The phenylphosphine is suggested to be formed by a complex ionic reaction between pentaphenylcyclopentaphos-... 

The kinetics of the oxidation of phenylphosphonous acid (132) to phenylphosphonic acid by chromic oxide have been investigated." The reaction, which is first order in Cr, is catalysed by both acid and pyridine and the mechanism suggested involves the initial formation of a complex between chromic acid and the tervalent form of the starting acid. Ratedetermining decomposition of this complex is followed by rapid oxidation by Cr. ... 

The reaction between (167) and NBA is set out in Scheme 22. In aqueous solution, the reaction proceeds cleanly nmr spectroscopic analysis indicates the formation of only one diastereoisomer of the acid (168 R=H) this acid was too labile for isolation but was isolated as a 1 1 mixture of the esters (168 R=Me) enantiomeric at phosphorus. Ozone reacted slowly with (167) in chloroform to give phenylphosphonous acid via (169) the last was characterized as (170). 

The entire range of Procion T dyes was based on one versatile intermediate, 3-aminophenylphosphonic acid (7.42), readily manufactured by nitration of phenylphosphonic acid followed by reduction (Scheme 7.29) In most instances this intermediate became the... 

The phenylphosphonic acid 197 reacts with 5 equiv. of AgC104 to deliver the 1,2-oxa-phosphol-3-ene-2-oxide 198 in an 80% total yield of the Z- and E-isomers (Scheme 15.63) [127]. For related reactions, see also [128]. With a phosphonic acid and Hg(OAc)2, the mercurated intermediate, a 4-acetoxymercury l,2-oxaphosphol-3-ene and the corresponding chloride after ligand exchange were isolated [129]. 

The reaction between phenylphosphonic dichloride and 2-naphthol in the presence of pyridine to give, ultimately, 2-naphthyl phenylphosphonic acid has been shown to be usefully influenced when DMF is added before the naphthol.40... 

The complexes [Mn(L2)(02PH2)2] (L2 = o-phen or bipy) have been re-ported and phenylphosphonic acid forms complexes with Mn in which ligand-bridging gives rise to cross-linked polymers of stoicheiometry MnL... 

Uses/Sources. Exposure to phenylphos-phine may occur when phenylphosphinates (used as catalysts and antioxidants) are heated above 200°C, yielding phenylphosphonic acid derivatives and phenylphosphine. 

Other hand, phenylphosphonous acid (461) reacts with diethyl acetylene-dicarboxylate to give diphosphinic acid (462) [Eq. (69)]. The adduct is probably obtained as the racemic form, though its configuration has not been confirmed. 

The hydrolytic products are benzyl alcohol and the corresponding enol phosphonate produced through carboxyl group participation. In the presence of hydroxylamine the products are diverted to benzyl phenylphosphonate and pyruvate oxime hydroxamate. These experimental results contrast markedly with those observed for the phosphoacetoin system. A simple explanation for the formation of benzyl phenylphosphonic acid is generation of the penta-covalent species (47)... 

Otu, E.O. The synergistic extraction of thorium(lV) and uranium(VI) by 2-ethylhexyl phenylphosphonic acid and micelles of dinonylnaphthalene sulphonic acid, Solvent Extr. Ion Exch. 15 (1997) 1-13. 

The structure-reactivity relationship of acidic organophos-phorus compounds is well demonstrated by mono-esters of p-substi-tuted phenylphosphonic acids. The acidity of these organic acids increased as the polar nature of the substituents enhanced. A linear free energy relationship exists between the pKa value and the Hammett cr constants in acidic p-substituted phenylphospho-nates. When these structure parameters are plotted either against the t POO" asym. or against the 31p chemical shift of their dicyclo-hexylammonium salts straight lines resulted in both cases. 

Ho, W.S.W. and Wang, B. (2002) Strontium removal by new alkyl phenylphosphonic acids in supported liquid membranes with strip dispersion. Industrial et Engineering Chemistry Research, 41, 381. 

Figure 4. CZE electropherogram of a standard mixture of 4 alkylphosphonates (solute concentration lmgL-1) CZE conditions 50cmLt (40cmLrf) x 50 pm ID V = -20kV Buffer 10 mM glutamic acid, 1 mM phenylphosphonic acid, 1 mM CAS-U, pH 3.22 indirect UV detection at 214nm. (Reprinted from J.E. Melanson, B.L.Y. Wong, C.A. Bouleti and C.A. Lucy, J. Chromatogr. A, 920, 359-365 (2001), reproduced with permission from Elsevier Science)...

Reversal of the direction of the EOF using the cationic surfactant didodecyldimethylammonium hydroxide (DDAOH) in reversed polarity mode has also been reported (16). The bromide form of this surfactant (DDAB (didodecyldimethylammonium bromide)) was converted to the hydroxide form to eliminate an undesirable system peak caused by bromide. Using 10 mM phenylphosphonic acid as the probe and a buffer consisting of 200 mM borate, 0.35 mM DDAOH, and 0.03% Trition X-100 at pH 4.0, the separation of 8 alkylphosphonates was achieved in less than 3 min. Eimits of detection were in the 100 xg/L range. 

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