Ring-Opening Polymerization of a Benzylated 1,6-Anhydro-β-D-talopyranose and Synthesis of a New Polysaccharide, (1-6)-α-D-Talopyranan
Ring-Opening Polymerization of a Benzylated 1,6-Anhydro-β-D-talopyranose and Synthesis of a New Polysaccharide, (1-6)-α-D-Talopyranan
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苄基化 1,6-脱水-β-D-吡喃糖的开环聚合及新多糖 (1-6)-α-D-吡喃喃的合成
DOI：
10.1021/ma9009577
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发表时间：
2009
期刊：
影响因子：
--
通讯作者：
Takashi Yoshida
中科院分区：
文献类型：
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作者：
K. Hattori;Takashi Yoshida
合成了1，6-脱水-2，3，4-三-O-苄基-β-d-塔罗吡喃糖（1），并对其聚合性能进行了比较。在二氯甲烷中，在−60 °C下，五氟化磷作为引发剂，得到数均分子量（Mn）为9500− 19600的有规立构聚合物（2）。根据聚合过程中羟基的构型和吡喃糖环的构象变化分析了聚合性。还比较了与1，6-脱水-2，3，4-三-O-苄基-β-d-吡喃葡萄糖（4）共聚所得的单体竞聚率。本发明的单体1需要大量的用于聚合的引发剂。聚合反应的~（31）P NMR结果表明，大量的引发剂不仅与单体的1，6-脱水环上的氧配位，而且与聚合物的氧配位。这种引发剂与聚合物氧的额外配位预期将降低聚合物的分子量。
1,6-Anhydro-2,3,4-tri-O-benzyl-β-d-talopyranose (1) was synthesized and polymerized to compare its polymerizability with that of other benzylated 1,6-anhydrohexopyranoses reported previously. In methylene chloride at −60 °C, phosphorus pentafluoride as the initiator gave stereoregular polymers (2) with number-average molecular weights (Mn) of 9500−19 600. The polymerizability was analyzed based on the configuration of the hydroxyl groups and conformational change of the pyranose ring during polymerization. The monomer reactivity ratios resulting from copolymerization with 1,6-anhydro-2,3,4-tri-O-benzyl-β-d-glucopyranose (4) were also compared. The present monomer 1 required a large amount of the initiator for polymerization. 31P NMR results of polymerization suggested that considerable amounts of the initiator coordinated with not only the oxygen of the 1,6-anhydro ring of the monomer but also those of the polymer. This additional coordination of the initiator with the polymer oxygens is expected to decre...