Photosolvolysis of O,O,S-trimethyl phosphorodithioate. Evidence for an SN1(P) mechanism
Abstract
Irradiation (254 nm) of (MeO)2P(S)SMe in ROH yields mainly (66%, R = Pri) the ionic photosolvolysis product (MeO)2P(S)OR with the very low capture ratio 1·9 ± 0·4 for R = Me vs. R = Pri under competitive photosolvolysis conditions, whereas irradiation in e.g. tetrahydrofuran and CH2Cl2 gives free-radical products, suggesting that the photoreactions proceed by way of an ‘intimate radical-ion pair.’