Alkali Metallosilicates: Synthesis, Structure and Evaluation in the ROP of ϵ‐Caprolactone
作者:Jovana Pérez‐Pérez、Uvaldo Hernández‐Balderas、Diego Martínez‐Otero、Mónica Moya‐Cabrera、Vojtech Jancik
DOI:10.1002/ejic.202100427
日期:2021.8.26
association of the alkali derivatives, and the size of the alkali metal influences the shape of the MxOx core. These compounds were studied as initiators in the ROP of ϵ-caprolactone, varying temperature, reaction-time, monomer/initiator ratio, metal center variation and association degree. The best results were achieved with [(tBuO)3SiO}4Li4] (1) producing an almost quantitive yield of polycaprolactone
一系列金属硅酸盐配合物 ( t BuO) 2 (RO)SiOM (R= t Bu, i Pr, Et, Me; M=Li, Na, K) 由定制的硅烷醇制备。复合物显示出不同程度的缔合,并在固态下具有异立方、双异立方或六棱柱骨架,而 ESI-MS 显示低聚物的碎裂。硅原子周围的空间位阻对碱衍生物的缔合有直接影响,碱金属的大小影响 M x O x的形状核。这些化合物在 ε-己内酯的 ROP 中作为引发剂进行了研究,不同的温度、反应时间、单体/引发剂比、金属中心变化和缔合度。[( t BuO) 3 SiO} 4 Li 4 ] ( 1 ) 获得了最好的结果,产生了几乎定量的聚己内酯(97 %,M n =35 kg mol -1,M w / M n =1.72) .