Wu Xiaojian, Ji Sunjun, Li Yi, Li Baozong, Zhu Xiulin, Hanabusa Kenji, Yang Yonggang
College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, PR China.
J Am Chem Soc. 2009 Apr 29;131(16):5986-93. doi: 10.1021/ja9001376.
A pair of chiral bola-type enantiomers, ll-12PyBr and dd-12PyBr, was synthesized. They can cause physical gels in pure water. Sol-gel transcriptions were carried out to control mesoporous 1,4-phenylene-silica nanostructures and helicity using the organic self-assemblies of these amphiphiles as templates. Under acidic conditions, left-handed helical 1,4-phenylene-silica bundles were prepared using the self-assemblies of ll-12PyBr as templates. Additionally, right-handed helical silica and 1,4-phenylene-silica bundles were prepared using the self-assemblies of dd-12PyBr as templates. Under basic conditions, 1,4-phenylene-silica bundles were also obtained. However, it is hard to determine the handedness. For all of the 1,4-phenylene-silica bundles, it is interesting to find that the aromatic rings are packing in helix within the wall of the pore channels. Powder X-ray diffraction patterns indicated that the aromatic rings of 1,4-phenylene-silica bundles prepared under basic conditions showed a greater degree of order than those of 1,4-phenylene-silica bundles prepared under acidic conditions. Moreover, helical silica, 1,3-phenylene-silica, ethene-silica, and ethane-silica bundles were also prepared using the self-assemblies ll-12PyBr and dd-12PyBr as templates.
合成了一对手性bola型对映体ll-12PyBr和dd-12PyBr。它们能在纯水中形成物理凝胶。以这些两亲分子的有机自组装体为模板,进行溶胶-凝胶转录以控制介孔1,4-亚苯基-二氧化硅纳米结构和螺旋性。在酸性条件下,以ll-12PyBr的自组装体为模板制备了左旋螺旋状的1,4-亚苯基-二氧化硅束。此外,以dd-12PyBr的自组装体为模板制备了右旋螺旋状二氧化硅和1,4-亚苯基-二氧化硅束。在碱性条件下也获得了1,4-亚苯基-二氧化硅束。然而,很难确定其旋向性。对于所有的1,4-亚苯基-二氧化硅束,有趣的是发现芳香环在孔道壁内呈螺旋状堆积。粉末X射线衍射图谱表明,碱性条件下制备的1,4-亚苯基-二氧化硅束的芳香环比酸性条件下制备的1,4-亚苯基-二氧化硅束具有更高的有序度。此外,还以ll-12PyBr和dd-12PyBr的自组装体为模板制备了螺旋状二氧化硅、1,3-亚苯基-二氧化硅、乙烯-二氧化硅和乙烷-二氧化硅束。