Solvent dependent mechanistic pathways for η-O2CCH3 substitution from the [Mo3(μ3-O)2(μ-O2CCH3)6(η-O2CCH3)3]− anion

We examine terminal acetate substitution at the [Mo3(μ3-O)2(μ-O2CCH3)6(η-O2CCH3)3]− anion. When the solvent is D2O or methanol-d4, we find that substitution follows the predicted D or ID pathway yet in the presence of acetic acid-d4, observed activation parameters point towards a more complex mechanism involving hydrolysis of the acetate ligand.