Mild depolymerization of silicone grease using aluminum(III)chloride:: high-yield synthesis and crystal structure of [{ClSiMe2OAlCl2}2], and its controlled hydrolysis on aluminum surfaces

Reaction of AlCl3 with {Me2SiO}(n) (Dow-Corning high-vacuum grease) at an Al: Si ratio of 1:1 in hexane at room temperature yielded a large crop of colorless crystals of [{ClSiMe2OAlCl2}(2)], which were characterized by single-crystal X-ray diffraction and NMR. These crystals hydrolyzed on an aluminum surface to give a coating of silicone oil interspersed with particles of [Al(OH2)(6)]Cl-3, as determined by powder X-ray diffraction and X-ray photoelectron spectrometry. Copyright (C) 2003 John Wiley Sons, Ltd.