title: Electrophilic trifluoromethylation of S-hydrogen phosphorothioates.
abstract: A series of S-hydrogen phosphorothioates have been converted to the corresponding S-trifluoromethyl derivatives upon reaction with the electrophilic trifluoromethylation reagent 1 (trifluoromethyl 1,3-dihydro-3,3-dimethyl-1,2-benziodoxole). Relative rate data were obtained by (19)F NMR monitoring of competition experiments and were evaluated by means of the Taft equation. A high positive polar sensitivity factor of 2.55 was found for electron-rich substrates and a negative one of -0.37 for electron-poor ones, implying the involvement of two different rate-determining steps. Furthermore, the reaction was found to be unaffected by steric factors.
authors.affiliation: Department of Chemistry and Applied Biosciences, Swiss Federal Institute of Technology, ETH Zürich, CH-8093 Zürich, Switzerland.
authors.forename: Nico
authors.initials: N
authors.lastname: Santschi
authors.forename: Antonio
authors.initials: A
authors.lastname: Togni