Solvent-free synthesis of pseudopolyrotaxane and polyrotaxane: Efficient threading complexation of a cyclodextrin wheel and a linear polymer axle to yield pseudopolyrotaxane and its fixation to polyrotaxane by the direct grinding of a solid mixture
Solvent-free synthesis of pseudopolyrotaxane and polyrotaxane: Efficient threading complexation of a cyclodextrin wheel and a linear polymer axle to yield pseudopolyrotaxane and its fixation to polyrotaxane by the direct grinding of a solid mixture
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DOI：
10.1002/pola.21913
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发表时间：
2007-04-15
影响因子：
--
通讯作者：
Takata, Toshikazu
中科院分区：
文献类型：
--
作者：
Liu, Runtao;Maeda, Takeshi;Takata, Toshikazu
不能通过溶液中以外的反应获得的化合物的无溶剂合成和固态合成具有重要意义或非常理想，这不仅是因为简单、经济和实用的制造，而且还因为环境相容性。1各种有机化合物，包括聚合物，实际上是在没有任何溶剂或固态的条件下合成的。然而，直到Takata等人，4 Tonelli等人，5和Harada等人6在2005年报告说。尽管Takata等人证明了假聚轮烷到聚轮烷的固态封端不能通过溶液中的反应获得，但Harada等人发现，只有当环糊精和线性聚合物的混合物在没有任何溶剂的情况下静置时才能形成假聚轮烷。虽然Harada et al.的方法是一种简单而有趣的无溶剂的线型聚合物的环糊精的线程，有一些问题需要解决，如非常长的反应时间和复杂的表征，除了没有达到衍生化的聚轮烷作为稳定的形式。当这些缺点可以被克服时，从迄今为止报道的合成困难和有限的互锁化合物的合成方法的一般方面来看，由轮和轴的混合物制备假聚轮烷并在无溶剂条件下将其固定到聚轮烷上可以为聚轮烷合成提供新颖且有效的方案。2，3在该通信中，我们公开了假聚轮烷和聚轮烷的非常有效的无溶剂合成，即，通过线性聚合物与环糊精的连接以及通过简单直接研磨材料混合物而不使用任何溶剂将它们固定到聚轮烷上来合成假聚轮烷。由于线性聚合物中羟基的通常酰化，甲基化环糊精被用作轮。
The solvent-free synthesis and solid-state synthesis of compounds that cannot be obtained by reactions other than those in solution are of great significance or really ideal not only because of simple, economical, and practical manufacturing but also because of environmental compatibility. 1 A variety of organic compounds, including polymers, are actually synthesized under conditions without any solvent or in the solid state. However, it had never been reported that interlocked compounds2, 3 could be obtained by solvent-free synthesis until Takata et al., 4 Tonelli et al., 5 and Harada et al. 6 reported that in 2005. Although Takata et al. demonstrated the solid-state end capping of pseudopolyrotaxane to polyrotaxane could not be obtained by a reaction in solution, Harada et al. found that pseudopolyrotaxane can be formed only if a mixture of cyclodextrins and linear polymers is allowed to stand without any solvent. Although Harada et al.’s method for the solvent-free threading of linear polymers to cyclodextrins is simple and quite interesting, there are a few problems to be solved, such as very long reaction times and difficult characterization of the complex, in addition to unattained derivation to polyrotaxane as the stable form. When such drawbacks can be overcome, the preparation of pseudopolyrotaxane from a mixture of a wheel and axle and its fixation to polyrotaxane under solvent-free conditions can provide a novel and effective protocol for polyrotaxane synthesis, judging from so far reported general aspects of the synthetic difficulty and the limited synthetic methods of interlocked compounds. 2, 3 In this communication, we disclose the very efficient solvent-free syntheses of pseudopolyrotaxane and polyrotaxane, that is, the syntheses of pseudopolyrotaxanes via the threading of linear polymers to cyclodextrins and their fixation to polyrotaxanes by a simple direct grinding of a mixture of materials without any solvent. Because of the usual acylation of the hydroxyl in the linear polymer, the methylated cyclodextrins were used as the wheels.