Two dinuclear aluminum complexes bearing dinaphthalene bridging Schiff bases have been synthesized and investigated as catalysts in ring-opening polymerization (ROP) of cyclic esters such as rac-lactide (rac-LA) and ε-caprolactone (ε-CL) and in the copolymerization (ROCOP) of phthalic anhydride (PA) with cyclohexene oxide (CHO) and limonene oxide (LO). The polymerizations of cyclic esters were living, producing polymers with narrow molar mass distributions. Kinetic studies showed that the polymerizations were first order with respect to the monomers. Cooperative effects between two metal centers, located in proximal positions, are invoked to rationalize the high activities toward both monomers, although the rigid backbone of the complexes enhances the reactivity of less encumbered caprolactone in comparison to lactide. Good activities were achieved also in the copolymerization of phthalic anhydride with cyclohexene epoxide and with the bioderived limonene oxide.

中文翻译：

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带有二萘酚基氨基酚盐配体的双金属铝配合物作为聚酯合成的催化剂

两种双核铝络合物轴承二萘桥接席夫碱已被合成和研究作为在环酯的开环聚合（ROP）催化剂，如外消旋-丙交酯（外消旋-LA）和ε-己内酯（ε-CL），以及邻苯二甲酸酐（PA）与环己烯氧化物（CHO）和柠檬烯氧化物（LO）的共聚（ROCOP）。环状酯的聚合反应活跃，产生具有窄摩尔质量分布的聚合物。动力学研究表明，聚合反应相对于单体而言是一阶的。尽管配合物的刚性骨架增强了与丙交酯相比较少阻碍的己内酯的反应性，但调用了位于近端位置的两个金属中心之间的协同作用以合理化对两种单体的高活性。在邻苯二甲酸酐与环己烯环氧化物和与生物衍生的柠檬烯的共聚中也获得了良好的活性。