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

Treatment of a N-arylanilido-imine ligand [ortho-C6H4(NHAr)CHN]2CH2CH2 (Ar = 2,6-Me2C6H3) (LH2) with one equiv. of AlMe3 affords a monometallic complex [C6H4(NHAr)–CHN)]CH2CH2(C6H4(NAr)CHNAlMe2) (1). The monometallic complex 1 reacts with one equiv. of ZnEt2 to give a heterobimetallic complex [C6H4(NAr)–CHNZnEt]CH2CH2[C6H4(NAr)–CHNAlMe2] (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.

Graphical abstractA heterobimetallic Al/Zn complex and a monometallic Al complex were synthesized. Both complexes are efficient catalysts for the ring-opening polymerization of ε-caprolactone in the presence of benzyl alcohol.Figure optionsDownload full-size imageDownload as PowerPoint slide