Mechanism of the rapid alkaline hydrolysis of a phosphoramidothioate ester

Insecticidal, anticholinesterase, and hydrolytic properties of S-aryl phosphoramidothioates

“…The reduction in kz is small compared to that found for other N-mono-and N,N-disubstituted phosphoramidates (Gerrard and Hamer, 1967 ;Traylor and Westheimer, 1965) and is readily explainable on the basis of a displacement reaction on phosphorus in which polar and steric effects from the second methyl group reduce the rate. The reduction in kz is small compared to that found for other N-mono-and N,N-disubstituted phosphoramidates (Gerrard and Hamer, 1967 ;Traylor and Westheimer, 1965) and is readily explainable on the basis of a displacement reaction on phosphorus in which polar and steric effects from the second methyl group reduce the rate.…”

“…DISCUSSION Considerable effort has been given to the study of the alkaline hydrolysis of phosphoramidate esters (Heath, 1956 ;Traylor and Westheimer, 1965;Gerrard and Hamer, 1967, 1969. This compound, therefore, is approximately of equal toxicity to houseflies and mice.…”

Preparation of the Enantiomers of Compounds Containing Chiral Phosphorus Centers

“…Boxed compounds are primary sources of P-chirality. e, (51,52,139,153). These results are for acyclic systems only (chiral P is not part of ring system).…”

Synthesis of Optically Active Cyclic Phosphorothionates and Phosphoramidothionates with Insecticidal Activity by Using a Chiral Phosphorylating Agent

“…Thus, it is presumed that the first step of oxazaphospholidine formation from a 2-aminoalcohol and MNPC is amidation accompmanied principally by P-CI bond cleavage and then followed by the attack of the hydroxyl group at the phosphorus atom to displace the nitrophenoxide as shown in Scheme 6. Since the amidation of phosphorochloridates proceeds with inversion of the configuration at phosphorus,ll) an oxazaphospholidine sulfide having the presumed phosphorus configuration may be produced by occurring of an intramolecular SN2-like reaction in a proposed intermediate (9). However, the hypothetical intermediate could not be detected by 31p-NMR during the reaction, suggesting that very rapid cyclizationoccurred because of the proximity of the reactive centers.…”

“…The procedures of Hilgetag 8 ) and Gerrard 9 ) for the resolution of methyl p-nitrophenyl hydrogen phosphorothioate and its chlorination were modified. Dimethyl p-nitrophenyl phosphorothionate The methostrychnium salts were converted to the silver salts by treating with silver nitrate in methanol.9) The ( + )-methostrychnium salt gave the (-)-silver salt, mp 178", 180°C, [ct]o-86°(c= 1.1, CH 3 CN).…”