Ring-opening Copolymerization Using a Chromium(III) catalyst with a Readily Available Aminotriphenolate Ligand
발표자
()
초록
내용
An alternating ring-opening copolymerization of cyclic anhydrides with a series of epoxides using a new chromium(III) complex (2) with a readily available aminotriphenolate ligand (LtBu,tBu) was studied. The single crystal structure of 2 has octahedral geometry in contrast to the general trigonal bipyramidal geometry of transition metal aminophenolate complexes. The complex 2 and a cocatalyst (bis(triphenylphosphine)iminium chloride or 4-dimethylaminopyridine) as a binary catalytic system produced perfectly alternating polyesters with high molecular weights and low dispersity at high selectivity. Also, differently substituted monomers could be applied and the thermal properties (Tg up to 180 ℃) of the resulting polyesters tuned by the monomer selection.