Carbon-phosphorus bond hydrolysis

The versatility of triphenylphosphme in synthesis is well-known. Hydrolysis of its fluorine-containing derivatives does not involve the carbon-fluorine bond but rather the carbon phosphorus bond. 

Although the carbon-phosphorus bond is believed to be extremely stable, several examples of the hydrolytic cleavage of the P-C bond in 1-aminoalkanephosphonic acid and their esters, in acidic and basic media, were described recently [24,30,93], Hydrolysis of... 

Tesls in pure water, river water, and activated sludge showed that commercial iriaryl phosphates and alkyl diphenyl phosphates undergo reasonably facile degradation by hydrolysis and biodegradation. The phosphonalcs can undergo biodegradation of the carbon-lo-phosphorus bond by certain microorganisms... 

Reactions of vinylphosphonates j2 with an equimolar amount of lithium dialkylcuprates J result in the formation of complexes 3 containing two different organic ligands. These complexes react with electrophiles in various ways. In each of them a diverse ligand plays the role of a nucleophile. Hydrolysis of 3 or alkylation with alkyl halides affords the corresponding phosphonates k and 5 comprising extended saturated carbon chains bonded to phosphorus. However, in a number of reactions with aldehydes, the complexes 3 were found to undergo almost completely selective transformation into carbinols 6... 

Phosphorus—Carbon Bond. The P—C bond is 0.184—0.194-nm long and has an energy of ca 272 kj/mol (65 kcal/mol). It is one of the more stable bonds formed by phosphoms, resistant to both hydrolysis and oxidation (7,8). Unlike the phosphoms—halogen or phosphoms—oxygen bonds, the P—C linkage is inert to exchange. A phosphoms atom connected to carbon behaves similarly to another carbon atom in a hydrocarbon chain. 

A. Alkaline Hydrolysis. -The low kinetic isotope effect observed in the protonation of carbanions formed in phosphonium salt hydrolysis leads to the idea that there is little breaking of the phosphorus-carbon bond and correspondingly little transfer of a proton to the incipient carbanion in the transition state (87) of the rate-determining step. ... 

On the basis of correlation analysis by LFER between the chemical structure and spectral data from IR and NMR, Lewis basicity, rate constant of hydrolysis as well as pKa of various organophos-phorus compounds, it is not likely that the benzene ring is conjugated with the phosphoryl group, and that the oxygen of the latter is linked to the phosphorus by a double bond, if the general concepts of conjugation in the chemistry of carbon compounds work as well in the phosphorus series. 

P-O bond fission is the usual mode of attack by nucleophiles on phosphodiesters, although there are exceptions. The labile diester methyl-2,4-dinitrophenyl phosphate shows significant amounts of attack at aromatic carbon (nucleophilic aromatic substitution, with loss of methyl phosphate) in competition with attack at phosphorus, most notably with hydroxide and with primary amines.46 Due to the small size of the methyl group it is sterically susceptible to nucleophilic attack in phosphate esters the hydrolysis of the dimethyl phosphate anion occurs almost exclusively by C-O bond fission.4 With larger or less labile leaving groups, even... 

Cleavage at the phosphorus-carbon bond in esters of (trichloromethyl)phosphonic acid under alkaline conditions has been known for many years and yields ethanol, phosphoric acid and chloroform, and a study of the kinetics has shown that as the concentration of alkali rises, CO, HCl and HCOOH are formed in increasing amounts, possibly through the sequence illustrated in Scheme 9. However, hydrolytic removal of the trichloromethyl group is possible in conditions other than alkaline. At pH 1-10, 4-nitrophenyl phenyl(trichloromethyl)phosphinate is cleaved at the P—C bond to the extent of90-100%, although this is accompanied by hydrolysis at the POC bonding with the liberation of small... 

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