含N，O-和N，S-席夫碱的铝配合物在ε-己内酯和l-丙交酯开环聚合中的比较研究,Inorganic Chemistry

当前位置： X-MOL 学术 › Inorg. Chem. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

含N，O-和N，S-席夫碱的铝配合物在ε-己内酯和l-丙交酯开环聚合中的比较研究
Inorganic Chemistry ( IF 4.3 ) Pub Date : 2015-11-17 00:00:00 , DOI: 10.1021/acs.inorgchem.5b01858
Meng-Chih Chang,Wei-Yi Lu,Heng-Yi Chang,Yi-Chun Lai,Michael Y. Chiang,Hsing-Yin Chen,Hsuan-Ying Chen

甲系的Al配合物轴承Schiff碱和硫-席夫碱配体的合成，以及它们用于ε己内酯的开环聚合（CL）和应用升研究了丙交酯（LA）。发现配位体的空间效应导致更高的聚合速率，最重要的是，与N，S-席夫碱的Al配合物比与N，O-席夫碱的Al配合物具有更高的聚合速率（CL聚合的5-12倍）和LA聚合的2-7倍）。利用密度泛函理论（DFT）研究了CL聚合反应的机理。该计算预测，与带有N，S-席夫碱配体的Al配合物（17.6 kcal / mol）相比，与具有N，S-席夫碱配体的Al配合物（19.0 kcal / mol）相比，活化能更低。（mol），并且活化能降低的幅度与实验中观察到的速率增强的幅度相当。活化能的降低归因于催化剂-底物的去稳定作用。在开环聚合过程中使用含硫配体降低活化能可能是设计具有高催化活性的新型铝配合物的新策略。

"点击查看英文标题和摘要"

Comparative Study of Aluminum Complexes Bearing N,O- and N,S-Schiff Base in Ring-Opening Polymerization of ε-Caprolactone and l-Lactide

A series of Al complexes bearing Schiff base and thio-Schiff base ligands were synthesized, and their application for the ring-opening polymerization of ε-caprolactone (CL) and l-lactide (LA) was studied. It was found that steric effects of the ligands caused higher polymerization rate and most importantly the Al complexes with N,S-Schiff base showed significantly higher polymerization rate than Al complexes with N,O-Schiff base (5–12-fold for CL polymerization and 2–7-fold for LA polymerization). The reaction mechanism of CL polymerization was investigated by density functional theory (DFT). The calculations predicted a lower activation energy for a process involved with an Al complex bearing an N,S-Schiff base ligand (17.6 kcal/mol) than for that of an Al complex bearing an N,O-Schiff base ligand (19.0 kcal/mol), and this magnitude of activation energy reduction is comparable to the magnitude of rate enhancement observed in the experiment. The reduction of activation energy was attributed to the catalyst–substrate destabilization effect. Using a sulfur-containing ligand to decrease the activation energy in the ring-opening polymerization process may be a new strategy to design a new Al complex with high catalytic activity.

更新日期：2015-11-17

点击分享查看原文

点击收藏

阅读更多本刊新发论文本刊介绍/投稿指南