Li Hui, Ollivier Jérôme, Guillaume Sophie M, Carpentier Jean-François
Univ Rennes, CNRS, ISCR-UMR 6226, 35000, Rennes, France.
Angew Chem Int Ed Engl. 2022 May 16;61(21):e202202386. doi: 10.1002/anie.202202386. Epub 2022 Mar 23.
We report here on the ring-opening polymerization (ROP) of racemic β-thiobutyrolactone (rac-TBL), as the first chemical synthesis of poly(3-thiobutyrolactone) (P3TB), the thioester analogue of the ubiquitous poly(3-hydroxybutyrate) (P3HB). The ROP reactions proceed very fast (TOF >12 000 h at r.t.) in the presence of various metal-based catalysts. Remarkably, catalyst systems based on non-chiral yttrium complexes stabilized by tetradentate amino alkoxy- or diamino-bis(phenolate) ligands {ONXO } (X=O, N) provide access to cyclic P3TB with either high isoselectivity (P up to 0.90) or high syndiotactic bias (P up to 0.70). The stereoselectivity can be controlled by manipulation of the substituents on the ligand platform and adequate choice of the reaction solvent and temperature as well. The cyclic polymer topology is evidenced by MALDI-ToF MS, NMR and TGA. Highly isotactic cyclic P3TB is a semi-crystalline material as revealed by DSC.
我们在此报告外消旋β-硫代丁内酯（rac-TBL）的开环聚合（ROP），这是首次化学合成聚（3-硫代丁内酯）（P3TB），它是普遍存在的聚（3-羟基丁酸酯）（P3HB）的硫酯类似物。在各种金属基催化剂存在下，ROP反应进行得非常快（室温下TOF>12000 h）。值得注意的是，基于由四齿氨基烷氧基或二氨基双（酚盐）配体{ONXO }（X = O，N）稳定的非手性钇配合物的催化剂体系能够制备出具有高异规选择性（P高达0.90）或高间同立构偏向性（P高达0.70）的环状P3TB。立体选择性可以通过操纵配体平台上的取代基以及适当选择反应溶剂和温度来控制。通过基质辅助激光解吸电离飞行时间质谱（MALDI-ToF MS）、核磁共振（NMR）和热重分析（TGA）证实了环状聚合物拓扑结构。差示扫描量热法（DSC）表明，高度全同立构的环状P3TB是一种半结晶材料。
