Activation of ligand reactivity: Thiolate C-S and dithiophosphate ester C-O heterolyses within a dimolybdenum(V) system

Ligand reactivity was demonstrated for sulfide alkylation, thiolate dealkyl ation, and dithiophosphate de-esterification within molybdenum(V) dimers. T he cationic complex [Mo-2(NC6H4Me)(2)(S2P(OEt)(2))(2)(mu-O2CMe)(mu-SR)(2)]( +) was inductively activated toward thiolate C-S and dithiophosphate C-O he terolyses. The dealkylations were studied using anionic nucleophiles, and v arious reactivity patterns were characterized. The de-esterification of the diethyl dithiophosphate ligands produced complexes containing the rare mon oester EtO(O)PS22- ligand. This ligand's phosphoryl group was poorly nucleo philic but weakly basic. Crystallographic comparisons between the activated cation and the neutral complex [Mo-2(NC6H4Me)(2)(S2P(OEt)(2))(2)(mu-O2CMe) (mu-S)(mu-SMe)] were conducted to delineate structural differences related to the activation. A crystallographic study was also done of the complex [M o-2(NC6H4CH3)(2)(S2P(OEt)(2))(S2P(O)OEt)(mu-O2CMe)(mu-SEt)(2)], which provi ded internal comparison of monoester EtO(O)PS22- and diester (EtO)(2)PS2- l igand types.