AbstractA method of preparation of a lattice‐disordered (or amorphous) zinc dimethoxide was explored, involving the reaction of diethylzinc with methanol under reflux in methanol solution. The amorphous zinc dimethoxide thus obtained, showed extremely high activity for propylene oxide polymerization. This polymerization is of living type and follows a first order rate law for the disappearance of monomer. The activity of the amorphous zinc dialkoxide decreases in the presence of ethylzinc alkoxide or alcohol. On change of solvent, the polymerization rate is found to depend on coordination strength of solvent, rather than on its dielectric constant. Polymerization of propylene oxide catalyzed by the diethylzinc/alcohol system is discussed in terms of a coordinate anionic mechanism.