Small Activation Enthalpy Research Articles

The solvolysis of 2-pyridyltrimethyl-silane, -germane, and -stannane by alcohols and by water

2-Pyridyltrimethyl-stannane and -germane, like the silane, react with water or methanol to give pyridine and trimethyltin(germanium) hydroxide or trimethyltin(germanium) methoxide. The relative rates of hydrolysis of 2-Me3MC5H4N (M = Si 1, Ge ∼ 10–4, Sn 22) are consistent with a reaction mechanism involving rate-determining nucleophilic substitution by the oxygen of the solvent on the metal through a 5-centred cyclic activated complex. Small activation enthalpies, high negative activation entropies, and the absence of a solvent isotope effect support this mechanism.