A series of titanium (Ti) compounds bearing 2,6-bis(o-hydroxyalkyl)pyridine ligands were synthesized and investigated as catalysts for the ring-opening polymerization of ε-caprolactone (CL) and L-lactide (LA). The Ti complexes with electron-withdrawing groups in pyridine rings or steric bulky groups in hydroxymethyl groups reduced the catalytic activity in CL and LA polymerizations, and ^MeL^Ph-TiOPr₂ exhibited the highest catalytic activity ([CL] = 0.5 M, [CL]:[Cat] = 100:8, 60 °C, 7.5 h, conversion = 93%; [LA] = 0.5 M, [LA]:[Cat] = 100:8, 60 °C, 3.5 h, conversion = 98%). The density functional theory calculation results revealed that CL interacted with the ligand through weak hydrogen bonds, and then approached the Ti center. After being attacked by isopropyl oxide, the carbonyl group of CL bonded to the Ti center. After the rearrangement and ring opening of CL ring, CL was converted to poly-ε-caprolactone.

合成了一系列带有2,6-双（邻羟基烷基）吡啶配体的钛（Ti）化合物，并研究了它们作为ε-己内酯（CL）和L-丙交酯（LA）开环聚合的催化剂。在吡啶环中具有吸电子基团或在羟甲基中具有空间大体积基团的Ti络合物降低了CL和LA聚合反应的催化活性，^Me L ^Ph -TiOPr ₂表现出最高的催化活性（[CL] = 0.5 M，[CL ]：[Cat] = 100：8，60°C，7.5 h，转化率= 93％; [LA] = 0.5 M，[LA]：[Cat] = 100：8，60°C，3.5 h，转化率= 98％）。的密度泛函理论计算结果表明CL通过弱氢键与配体相互作用，然后到达Ti中心。在被异丙氧化物侵蚀后，CL的羰基键合到Ti中心。在CL环的重排和开环后，CL被转化为聚-ε-己内酯。