133984-36-8Relevant articles and documents
Solvolysis of allylic isoprene phosphorothioate esters. A mechanistic study of the thiono → thiolo rearrangement
Poulter, C. Dale,Mautz, Douglas S.
, p. 4895 - 4903 (2007/10/02)
The reactions of O,O-dimethyl O-geranyl phosphorothionate (1-OPS(OMe)2), O,O-dimethyl S-geranyl phosphorothiolate (1-SPO(OMe)2), and O,O-dimethyl S-lianlyl phosphorothiolate (2-SPO(OMe)2) were studied in 65:35 TFE/water. Solvolysis of 1-OPS(OMe)2 at 20°C gave substantial amounts of thiolo isomers 1-SPO(OMe)2 and 2-SPO(OMe)2, along with smaller quantities of solvent addition products. At 40-65deg;C, rearrangement of linalyl phosphorothiolate 2-SPO(OMe) to geranyl phosphorothiolate 1-SPO(OMe)2 reacted at 90-120°C to give substitution products and 1-SPO2(OMe)2, formed by hydrolysis of a methyl. The relative reactivities of 1-OPS(OMe)2, 1-SPO(OMe)2, 2-SPO(OMe)2 are 1:(3 × 10-7):(6 × 10-3), respectively. From a combination of kinetic and trapping experiments, we estimate that 1-OPS(OMe)2 is 11 kcal/mol less stable than its thiolo isomer. A dissociative mechanism with ion-paired intermediates is proposed for the thiono → thiolo rearrangements, and the utility of the phosphorothioate moiety as a tool for studying reactions involving ion pairs is discussed.
