WACKER-Lehrstuhl für Makromolekulare Chemie, Zentralinstitut für Katalyseforschung (CRC), Technische Universität München , Lichtenbergstraße 4, 85747 Garching, Germany.
J Am Chem Soc. 2017 May 24;139(20):6787-6790. doi: 10.1021/jacs.7b01295. Epub 2017 May 15.
Terpolymerizations of (rac)-β-butyrolactone (BBL), cyclohexene oxide (CHO), and carbon dioxide were realized in one-pot reactions utilizing a Lewis acid BDI-Zn-N(SiMe) (1) catalyst. The type of polymerization can be regulated and switched between ring-opening polymerization (ROP) of BBL and CHO/CO copolymerization by the presence of CO in the reaction mixture. Applying 3 bar CO to the three-component system leads to similar reaction rates for copolymerization and ROP and therefore to a terpolymer with a statistical composition, whereas 40 bar CO affords exclusive copolymerization of CHO/CO. Two-dimensional NMR spectroscopy and polarimetry provided a deeper understanding of the underlying mechanism. Furthermore, copolymerization of cyclopentene oxide (CPO) and CO was performed, resulting in the highest reported TOF of 3200 h together with 99% polycarbonate selectivity. Terpolymerizations of CPO/CO and BBL were successfully conducted using the established reaction pathways.
（rac）-β-丁内酯（BBL）、环氧环己烷（CHO）和二氧化碳的三元共聚反应可在一锅反应中实现，利用路易斯酸 BDI-Zn-N（SiMe）（1）催化剂。通过在反应混合物中存在 CO，可以调节和切换聚合类型，在 BBL 的开环聚合（ROP）和 CHO/CO 共聚之间进行转换。在三元体系中施加 3 bar CO 会导致共聚和 ROP 的反应速率相似，从而得到具有统计组成的三元共聚物，而 40 bar CO 则会导致 CHO/CO 的选择性共聚。二维 NMR 光谱和旋光法提供了对基础机制的更深入理解。此外，还进行了环戊烯氧化物（CPO）和 CO 的共聚反应，获得了迄今为止最高的 3200 h-1 的 TOF 和 99%的聚碳酸酯选择性。使用已建立的反应途径成功地进行了 CPO/CO 和 BBL 的三元共聚反应。
