New Transacylation Catalysts: Silanes and Siloxanes Functionalized with 4-(Dialkylamino)pyridine Moieties

摘要

New silane monomers, which contain the 4-(dialkylamino)pyridine (DAAO) function,have been synthesized by hydrosilylation. The products were characterized by elemental analysis, infrared and 1H and 13C NMR spectroscopy, and gas chromatography-mass spectrometry. Hydrolysis-polycondensation of the respective difunctional monomers with a basic catalyst gave a mixture of linear homopolymer and cyclic oligomers from the monomer with a pendant DAAP residue and only the linear homopolymer from the monomer with the in-chain DAAP residue. The two linear homopolymers have different and unusual solubility properties in immiscible H2O/CH2Cl2 medium. The effect of pH on solubility and partition behavior of both polymers is discussed. These polymers are highly effective catalysts for acetylation of 1-methylcyclohexanol with acetic anhydride.