Heterobimetallic aluminium and zinc complex with N-arylanilido-imine ligand: Synthesis, structure and catalytic property for ring-opening polymerization of ε-caprolactone

Abstract

Treatment of a N-arylanilido-imine ligand [ ortho-C 6H 4(NHAr)CH N] 2CH 2CH 2 (Ar = 2,6-Me 2C 6H 3) ( LH 2) with one equiv. of AlMe 3 affords a monometallic complex [C 6H 4(NHAr)–CH N)]CH 2CH 2(C 6H 4(NAr)CH NAlMe 2) ( 1). The monometallic complex 1 reacts with one equiv. of ZnEt 2 to give a heterobimetallic complex [C 6H 4(NAr)–CH NZnEt]CH 2CH 2[C 6H 4(NAr)–CH NAlMe 2] ( 2). Both complexes were characterized by 1H and 13C NMR spectroscopy and elemental analyses, and the molecular structures of 1 and 2 were determined by X-ray diffraction analysis. The complexes 1 and 2 both are efficient catalysts for ring-opening polymerization of ε-caprolactone in the presence of benzyl alcohol yielding polymers with narrow polydispersity values and complex 2 initiates the polymerization in a controllable manner.