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含guanidine-phenolate配体的Ti和Zr复合物:协调化学和聚合研究

Víctor Flores-Romero¹, Jesse LeBlanc¹, Zichuan Chen¹

¹York University 4700 Keele Street Toronto Ontario M3J 1P3 Canada glavoie@yorku.ca.

|August 19, 2024

概括

新的4组金属复合物催化了raceme乳酸的聚合,产生具有异质性偏差的多乳酸. 催化剂在这种聚合过程中显示出比催化剂更高的活性.

科学领域:

有机金属化学有机金属化学
聚合催化法聚合催化法
材料科学材料科学材料科学

背景情况:

第4组金属复合物被广泛研究为聚合反应的催化剂.
瓜尼丁-酸连接物为金属中心提供独特的协调环境.
聚乳酸 (PLA) 生产对于可持续的聚合物开发至关重要.

研究的目的:

为了合成和表征4组bis (((异氧化物) 复合物与瓜尼丁-酸联体.
评估这些复合物的催化活性,在racemic乳化物的聚合.
用相关的二化复合物研究乙烯的聚合.

主要方法:

合成M[N^O]2(OiPr) 2复合物 (M=第4组金属) 的合成,其中包括瓜尼丁-酸联体.
在130°C的温度下无溶剂聚合未经净化的racemic乳化物.
使用Ti[N^O]2Cl2复合物的乙烯聚合.

主要成果:

合成的复合物有效催化了乳酸聚合的raceme,产生异质性多乳酸 (PLA) P_r = 0.56-0.62.
与Ti类似物相比,Zr复合物具有较高的催化活性 (1.17-3.21 × 10^-4 s^-1).
二化复合物在乙烯聚合过程中表现出较低的活性,这归因于联体电子和固体效应.

结论:

第4组瓜尼丁-酸盐复合物是生产异质性PLA的可行催化剂.
催化剂活性取决于金属中心,Zr的性能优于Ti.
连接物特性显著影响乳和乙烯聚合过程中的催化剂性能.

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