Department of Applied Chemistry, Osaka University, 2-1 Yamada-oka, Suita 565-0871, Japan.
Chemistry. 2010 Jul 12;16(26):7859-64. doi: 10.1002/chem.200903545.
An enantiomeric binaphthyl unit was tethered to adjacent thiophenes with oxyethylene linkers to give a chiral polythiophene with binaphthocrown ether cavities. Upon inclusion of a chiral cationic guest in the cavity of the chiral crown ether-polythiophene conjugate, the bithiophene unit was twisted to shorten the effective conjugation length of polythiophene backbone, enabling us to sense the guest binding by reading out the amplified optical signal gains arising from the backbone structure change. This strategy allowed us to discriminate the guest chirality without using chiroptical signals or a circular dichroism spectrometer to achieve the highest enantioselectivity of 7.3 for valine methyl ester with a 40-fold enhanced sensitivity compared with the corresponding monomeric sensor.
将手性联萘单元通过氧亚乙基链接连接到相邻的噻吩上，得到具有联萘冠醚空腔的手性聚噻吩。在手性冠醚-聚噻吩共轭物的空腔中包含手性阳离子客体时，双噻吩单元发生扭曲，从而缩短聚噻吩主链的有效共轭长度，使我们能够通过读取由主链结构变化引起的放大光学信号增益来检测客体结合。该策略允许我们在不使用圆二色性信号或圆二色分光光度计的情况下区分客体手性，从而实现了缬氨酸甲酯的最高对映选择性 7.3，与相应的单体传感器相比，灵敏度提高了 40 倍。
