二氧化碳和环氧化物的开环共聚是制备脂肪族聚碳酸酯和增加CO 2价值的有用手段。最近,第一个异双核 Zn( II )/Mg( II ) 催化剂表现出比任一同双核类似物更高的活性 ( J. Am. Chem. Soc. 2015 , 137, 15078–15081)。基于这一初步发现,本文制备并表征了八种具有羧酸盐共配体的新型 Zn( II )/Mg( II ) 异双核催化剂。最好的催化剂在使用环己烯氧化物(TOF = 8880 h -1、20 bar CO 2、120 °C、0.01 mol% 催化剂负载量)或环戊烯氧化物时表现出非常高的共聚活性。所有催化剂在低压状态下特别是在1巴压力CO 2下均具有高活性。使用原位光谱和等分技术分析聚合动力学:速率定律总体上是二阶的,催化剂和环氧化物浓度都具有一阶依赖性,二氧化碳压力为零阶。比较催化剂系列的伪一级速率系数值,差异主要归因于对引发速率的影响
The present invention provides novel catalysts of formula (I), where M
1
and M
2
are different and are independently selected from Mg, Zn, Fe, Co, Al and Cr, and catalyst systems comprising these catalysts. The invention also relates to the use of the inventive catalysts and catalyst systems to catalyse the reaction between i) carbon dioxide and an epoxide, ii) an epoxide and an anhydride, or iii) a lactide and/or a lactone. The invention also relates to a method for producing a catalyst of formula (I).
Heterodinuclear Mg(II)M(II) (M=Cr, Mn, Fe, Co, Ni, Cu and Zn) Complexes for the Ring Opening Copolymerization of Carbon Dioxide/Epoxide and Anhydride/Epoxide
作者:Natalia V. Reis、Arron C. Deacy、Gloria Rosetto、Christopher B. Durr、Charlotte K. Williams
DOI:10.1002/chem.202104198
日期:2022.3.7
A series of new heterodinuclear complexes comprising Mg(II)M(II) are reported as highly efficient catalysts for both the ROCOP of CO2/cyclohexene oxide and norbornene anhydride/cyclohexene oxide. Mg(II)Co(II) and Mg(II)Fe(II) were the most effective combinations in the catalysis.
Dinuclear metal catalysts: improved performance of heterodinuclear mixed catalysts for CO<sub>2</sub>–epoxide copolymerization
作者:P. K. Saini、C. Romain、C. K. Williams
DOI:10.1039/c3cc49158g
日期:——
A catalyst system comprising homo- and heteronuclear Zn–Mg complexes shows excellent polymerization control and exhibits higher activity than the homodinuclear catalysts for CO2–epoxide copolymerization.