手性席夫碱钴配合物在环氧丙烷与二氧化碳交替共聚中配体交换作用的研究

The Role of Ligand Exchange in Salen Cobalt Complexes in the Alternating Copolymerization of Propylene Oxide and Carbon Dioxide.

机构信息

Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, Leninskiy Av., 29, 119991 Moscow, Russia.

Faculty of Chemistry, Lomonosov Moscow State University, Lenin Hills, 1, Bld. 3, 119991 Moscow, Russia.

出版信息

Int J Mol Sci. 2024 Oct 11;25(20):10946. doi: 10.3390/ijms252010946.

DOI:10.3390/ijms252010946

PMID:39456728

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC11508113/

Abstract

A comparative study of the copolymerization of racemic propylene oxide (PO) with CO catalyzed by racemic (salcy)CoX (salcy = ,'-bis(3,5-di--butylsalicylidene)-1,2-diaminocyclohexane; X = perfluorobenzoate (OBzF) or 2,4-dinitrophenoxy (DNP)) in the presence of a [PPN]Cl ([PPN] = bis(triphenylphosphine)iminium) cocatalyst is performed in bulk at 21 °C and a 2.5 MPa pressure of CO. The increase in the nucleophilicity of an attacking anion results in the increase in the copolymerization rate. Racemic (salcy)CoX provides a high selectivity of the copolymerization, which can be higher than 99%, and the living polymerization mechanism. Poly(propylene carbonate) (PPC) with bimodal molecular weight distribution (MWD) is formed throughout copolymerization. Both modes are living and are characterized by low dispersity, while their contribution to MWD depends on the nature of the attacking anion. The racemic (salcy)CoDNP/[PPN]DNP system is found to be preferable for the production of PPC with a high yield and selectivity.

摘要

手性（salcy）CoX（salcy = ,'-双（3,5-二-叔丁基水杨醛）-1,2-二氨基环己烷；X = 全氟苯甲酸盐（OBzF）或 2,4-二硝基苯氧基（DNP））在[PPN]Cl（[PPN] = 双（三苯基膦）亚胺）助催化剂存在下，在 21°C 和 2.5 MPa 压力的 CO 下进行本体共聚。亲核性增加会导致共聚速率增加。手性（salcy）CoX 提供了高的共聚选择性，可以高于 99%，以及活性聚合机理。在共聚过程中形成了具有双峰分子量分布（MWD）的聚（碳酸丙烯酯）（PPC）。两种模式都是活性的，具有低分散性，而它们对 MWD 的贡献取决于进攻阴离子的性质。发现手性（salcy）CoDNP/[PPN]DNP 体系有利于高产率和高选择性地生产 PPC。