Conformational Studies on an Optically Active 1,4-Polyketone in Solution
Conformational Studies on an Optically Active 1,4-Polyketone in Solution
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溶液中光学活性 1,4-聚酮的构象研究
DOI：
10.1021/ma025979i
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发表时间：
2003
期刊：
影响因子：
5.5
通讯作者：
Takayoshi Matsumoto
中科院分区：
文献类型：
--
作者：
Naoyuki Kosaka;K. Nozaki;T. Hiyama;M. Fujiki;N. Tamai;Takayoshi Matsumoto
用CD和ORD光谱旋光法和静态光散射折射法研究了手性聚(S)-1-氧代-2-甲基三亚甲基(1)在溶液中的构象。1的变温CD和ORD光谱与1的模型化合物手性二酮(S)-3-甲基-2，5-己二酮(3)的变温CD和ORD光谱相比较，没有发现聚酮1形成稳定的螺旋构象的证据。静态光散射折射法测得1的相对分子质量为18 80 0，小于凝胶渗透色谱测得的相对分子质量2 7 6 0 0，表明存在延伸构象。静态光散射法测得其数均方根回转半径Rg，n为9.94 nm。
Conformation of a chiral γ-polyketone, poly((S)-1-oxo-2-methyltrimethylene) (1), in solution was investigated by CD and ORD spectropolarimetry and static light scattering refractometry. Variable-temperature CD and ORD spectra of 1 as compared with that of a chiral diketone (S)-3-methyl-2,5-hexanedione (3), a model compound of 1, afforded no evidence of polyketone 1 forming stable helical conformation. Static light scattering refractometry showed Mw value of 1 was 18 800, smaller than Mw 27 600 measured by GPC, indicating the existence of an extended conformation. The number-average root-mean-square radius of gyration Rg,n is evaluated to be 9.94 nm by static light scattering.