Kinetic constants k2 have been obtained for the reaction of sulfur with 25 PIII compounds in toluene or hexane. In the series PhnMe3-nP (n= 1− 3) or PhnBu3-nP (n= 0− 3), log k2 decreases linearly with∑ χi (χi= Tolman's electronic parameter of each ligand on P), taken as a gauge for the donor strength of P. Dramatic deviations from additivity are observed for the series PhnP (OEt) 3-n, PhnP (OPh) 3-n and BunP (OEt) 3-n (n= 0–3); the deviation is ...
