Helicity Induction of Polyisocyanate with a Crown Cavity on the Main Chain Synthesized by Cyclopolymerization of α,ω-Diisocyanate
作者:Ryosuke Sakai、Toshifumi Satoh、Ryohei Kakuchi、Harumi Kaga、Toyoji Kakuchi
DOI:10.1021/ma0496448
日期:2004.6.1
Polymerization of a novel α,ω-diisocyanate monomer, 1,14-bis(4-isocyanatophenoxy)-3,6,9,12-tetraoxatetradecane (1), was carried out in DMF using MeLi to afford a gel-free linear polymer according to a cyclopolymerization mechanism. The resulting polymer was assignable to poly(phenyl isocyanate) with a C2 symmetrical crown cavity on the main chain (2). The circular dichroism (CD) spectrum of 2 in the
在DMF中使用MeLi进行新型α,ω-二异氰酸酯单体1,14-双(4-异氰酸根合苯氧基)-3,6,9,12-四氧杂环丁烷(1)的聚合反应,得到无凝胶的线性聚合物根据环聚合机理。所得聚合物可归属于在主链(2)上具有C 2对称冠腔的聚(异氰酸苯酯)。在1-苯基甘氨酸(1- Pgly·HClO 4)的高氯酸盐存在下,圆二色性(CD)谱图2表现出负的棉花效应,强度为-3.2×10 4 deg cm 2 dmol -1在从245至330nm的范围内,对应于聚合物主链的吸收,同时,观察到阳性Cotton效应为d -Pgly·高氯酸4,并且CD光谱模式是的那个的镜像2与升-Pgly ·HClO 4。因此,这表明在主链(2)上具有冠状腔的新型聚(异氰酸苯酯)形成了一种单螺旋结构,该结构由主客体与手性客体分子驱动而形成。尽管溶剂显着影响2的CD强度,但CD强度在任何温度下都几乎不变。