Kong Wei-Li, Wang Zhong-Xia
CAS Key Laboratory of Soft Matter Chemistry and Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
Dalton Trans. 2014 Jun 28;43(24):9126-35. doi: 10.1039/c4dt00431k.
Synthesis and characterization of novel dinuclear magnesium, zinc and aluminum complexes supported by bis(iminopyrrolide) ligands and their catalysis toward the ring-opening polymerization (ROP) of ε-caprolactone (ε-CL) and rac-lactide (rac-LA) were carried out. The ligand precursors [(5-Bu(t)-2-C4H2NH)CH=N(CH2)2]2NH (H2L(Bu), 1) and [(2-C4H3NH)CH=N(CH2)2]2NH (H2L(H), 2) were prepared by condensation of diethylene triamine with 5-tert-butyl-1H-pyrrole-2-carbaldehyde and 1H-pyrrole-2-carbaldehyde, respectively. Treatment of 1 with 2 equiv. of Bu(n)MgOBn in toluene at 70 °C produced dinuclear magnesium complex [(μ-OBn)2Mg2L(Bu)] (3). Similar treatment of 1 with EtZnOBn generated [(μ-OBn)2Zn2L(Bu)] (4). Reaction of 2 with 2 equiv. of Me2AlOBn in toluene at 70 °C afforded aluminum complex [Me2Al(μ-OBn)2AlL(H)] (5). Complexes 3-5 were characterized by (1)H and (13)C NMR spectroscopy, elemental analyses, and single crystal X-ray diffraction techniques. Each of complexes 3-5 is active for the ROP of ε-CL and rac-LA. Kinetic studies of the polymerization reactions were performed.
开展了由双（亚氨基吡咯啉）配体支撑的新型双核镁、锌和铝配合物的合成与表征，以及它们对ε-己内酯（ε-CL）和外消旋丙交酯（rac-LA）的开环聚合（ROP）的催化作用。配体前体[(5-Bu(t)-2-C4H2NH)CH=N(CH2)2]2NH（H2L(Bu)，1）和[(2-C4H3NH)CH=N(CH2)2]2NH（H2L(H)，2）分别通过二亚乙基三胺与5-叔丁基-1H-吡咯-2-甲醛和1H-吡咯-2-甲醛缩合制备。在70℃下，将1与2当量的正丁基镁苄醇盐在甲苯中处理，得到双核镁配合物[(μ-OBn)2Mg2L(Bu)]（3）。用乙基锌苄醇盐对1进行类似处理，生成[(μ-OBn)2Zn2L(Bu)]（
