6224-65-3Relevant articles and documents
Mechanism of sulfur transfer from 1,2,4-dithiazolidine-3,5-diones to triphenylphosphines
Ponomarov, Oleksandr,Padelkova, Zdenka,Hanusek, Jiri
supporting information, p. 560 - 564 (2013/07/26)
The mechanism of sulfurization of substituted triphenylphosphines with 4-(3- and 4-substituted)-1,2,4-dithiazolidine-3,5-diones in acetonitrile, dichloromethane, tetrahydrofuran and toluene at 25°C was studied. The reaction pathway involves rate-limiting initial nucleophilic attack of the phosphorus at sulfur followed by fast decomposition of the phosphonium intermediate to the corresponding phosphine sulfide, phenylisocyanate and carbonylsulfide. From the Hammett correlations and from the solvent dependency, it was concluded that the transition-state structure is very polar and resembles the zwitter-ionic intermediate. The extent of P-S bond formation and S-S bond cleavage is very similar in the solvents series, but the latter gradually decreases with the decreasing polarity of the solvent. Copyright 2013 John Wiley & Sons, Ltd. The mechanism of sulfurization of substituted triphenylphosphines with 4-(3- and 4-substituted)-1,2,4-dithiazolidine-3,5- diones in acetonitrile, dichloromethane, tetrahydrofuran and toluene at 25°C was studied. The reaction pathway involves rate-limiting initial nucleophilic attack of the phosphorus at sulfur followed by fast decomposition of the phosphonium intermediate to the corresponding phosphine sulfide, phenylisocyanate and carbonylsulfide. The transition-state structure is very polar and resembles the zwitter-ionic phosphonium intermediate. Copyright
Mechanism of the sulfurisation of phosphines and phosphites using 3-amino-1,2,4-dithiazole-5-thione (xanthane hydride)
Hanusek, Jiri,Russell, Mark A.,Laws, Andrew P.,Jansa, Petr,Atherton, John H.,Fettes, Kevin,Page, Michael I.
, p. 478 - 484 (2008/03/27)
Contrary to a previous report, the sulfurisation of phosphorus(iii) derivatives by 3-amino-1,2,4-dithiazole-5-thione (xanthane hydride) does not yield carbon disulfide and cyanamide as the additional reaction products. The reaction of xanthane hydride with triphenyl phosphine or trimethyl phosphite yields triphenyl phosphine sulfide or trimethyl thiophosphate, respectively, and thiocarbamoyl isothiocyanate which has been trapped with nucleophiles. The reaction pathway involves initial nucleophilic attack of the phosphorus at sulfur next to the thiocarbonyl group of xanthane hydride followed by decomposition of the phosphonium intermediate formed to products. The Hammett ρ-values for the sulfurisation of substituted triphenyl phosphines and triphenyl phosphites in acetonitrile are ～ -1.0. The entropies of activation are very negative (-114 ± 15 J mol-1 K-1) with little dependence on solvent which is consistent with a bimolecular association step leading to the transition state. The negative values of ΔS ≠ and ρ values indicate that the rate limiting step of the sulfurisation reaction is formation of the phosphonium ion intermediate which has an early transition state with little covalent bond formation. The site of nucleophilic attack has been also confirmed using computational calculations. The Royal Society of Chemistry 2007.
A convenient alternative to prepare phosphine sulfides
Miranda,Salas,Mondragon,Velasco
, p. 1077 - 1080 (2007/10/02)
An efficient procedure to obtain phosphine sulfides by means of their corresponding phosphines in presence of sodium polisulfide solution, is described. Reaction yields are high and the work-up is very simple.
