Laboratoire Catalyse et Organométalliques, CNRS, Université de Rennes 1, Sciences Chimiques de Rennes (UMR 6226), Campus de Beaulieu, 35042 Rennes Cedex, France.
Chemistry. 2010 Dec 10;16(46):13805-13. doi: 10.1002/chem.201001111.
Six-membered cyclic carbonates, namely trimethylene carbonate (TMC), 3,3-dimethoxytrimethylene carbonate (DMTMC) and 3-benzyloxytrimethylene carbonate (BTMC), undergo controlled "immortal" ring-opening polymerization (iROP) under mild conditions (bulk, 60-150 °C), by using organocatalysts, including an amine [4-N,N-dimethylaminopyridine (DMAP)], a guanidine [1,5,7-triazabicyclo-[4.4.0]dec-5-ene (TBD)], or a phosphazene [2-tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3,2-diazaphosphorine (BEMP)], in the presence of an alcohol [benzyl alcohol (BnOH), 1,3-propanediol (PPD), glycerol (GLY)] that acts as both a co-initiator and a chain-transfer agent. Remarkably, such organocatalysts remain highly active in the iROP of technical-grade, unpurified TMC. Under optimized conditions, as much as 100,000 equivalents of TMC were fully converted by as little as 10 ppm of BEMP with the simultaneous growth of as many as 200 polymer chains, allowing the preparation of high molar mass poly(trimethylene carbonate)s (up to 45,800 g mol(-1)). These catalyst systems enable among the highest activities (TOF=55,800 h(-1)) and productivities (TON=95,000) ever reported for the ROP of TMC.
六元环碳酸酯，如三亚甲基碳酸酯（TMC）、3,3-二甲氧基三亚甲基碳酸酯（DMTMC）和 3-苯氧基亚甲基碳酸酯（BTMC），在温和条件下（本体，60-150°C），使用有机催化剂，包括胺[4-N,N-二甲基氨基吡啶（DMAP）]、胍[1,5,7-三氮杂二环[4.4.0]癸-5-烯（TBD）]或磷杂环戊二烯[2-叔丁基亚氨基-2-二乙基氨基-1,3-二甲基全氢-1,3,2-二氮杂磷环戊烯（BEMP）]，在醇[苄醇（BnOH）、1,3-丙二醇（PPD）、甘油（GLY）]的存在下，作为共引发剂和链转移剂，可以控制“不朽”开环聚合（iROP）。值得注意的是，这种有机催化剂在技术级未纯化 TMC 的 iROP 中仍然保持高度活性。在优化条件下，只需 10ppm 的 BEMP 就可以完全转化多达 100,000 当量的 TMC，同时生长多达 200 个聚合物链，从而可以制备高摩尔质量的聚（三亚甲基碳酸酯）（高达 45,800gmol(-1)）。这些催化剂体系使 TMC 的 ROP 活性（TOF=55,800h(-1)）和产率（TON=95,000）达到了有史以来的最高水平。
