Ring opening polymerization of lactides and lactones by multimetallic alkyl zinc complexes derived from the acids Ph 2 C(X)CO 2 H (X = OH, NH 2 )
Ring opening polymerization of lactides and lactones by multimetallic alkyl zinc complexes derived from the acids Ph 2 C(X)CO 2 H (X = OH, NH 2 )
复制标题
通过酸 Ph 2 C(X)CO 2 H (X = OH, NH 2 ) 衍生的多金属烷基锌配合物进行丙交酯和内酯的开环聚合
DOI：
10.1039/c6ra26746g
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发表时间：
2017
期刊：
影响因子：
3.9
通讯作者：
Al-Khafaji Y
中科院分区：
文献类型：
--
作者：
Al-Khafaji Y
二烷基锌试剂R2Zn与酸2，2-Ph2C(X)(CO2H)在甲苯中回流反应得到四核环配合物[RZN(DPG)]4，其中R=Me(1)，Et(2)，2-CF3C6H4(3)和2，4，6-F3C6H2(4)；报道了1·(2MeCN)，3和4·(4(C7H8)·1.59(H2O))的晶体结构，以及中间体(2-CF3C6H4)3B·MeCN和已知化合物[ZnCl2(NCMe)2]的晶体结构。本文报道了化合物1-4和已知的配合物[(Znet)_3(Znl)_3(Benz)_3](5；L=MeCN)在无苯甲醇的条件下催化ε-己内酯(ε-CL)、δ-戊内酯(δ-VL)和RAC-丙交酯(RAC-LA)的开环聚合反应，并研究了ε-CL与RAC-LA的共聚反应。含氟芳基的配合物3和4在锌原子上的活性最高。
The reaction of the dialkylzinc reagents R2Zn with the acids 2,2-Ph2C(X)(CO2H), where X = NH2, OH, i.e. 2,2′-diphenylglycine (dpgH) or benzilic acid (benzH2), in toluene at reflux temperature afforded the tetra-nuclear ring complexes [RZn(dpg)]4, where R = Me (1), Et (2), 2-CF3C6H4 (3), and 2,4,6-F3C6H2 (4); complex 2 has been previously reported. The crystal structures of 1·(2MeCN), 3 and 4·(4(C7H8)·1.59(H2O)) are reported, along with that of the intermediate compound (2-CF3C6H4)3B·MeCN and the known compound [ZnCl2(NCMe)2]. Complexes 1–4, together with the known complex [(ZnEt)3(ZnL)3(benz)3] (5; L = MeCN), have been screened, in the absence of benzyl alcohol, for their potential to act as catalysts for the ring opening polymerization (ROP) of ε-caprolactone (ε-CL), δ-valerolactone (δ-VL) and rac-lactide (rac-LA); the co-polymerization of ε-CL with rac-LA was also studied. Complexes 3 and 4 bearing fluorinated aryls at zinc were found to afford the highest activities.