College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China.
Langmuir. 2010 Jun 1;26(11):9040-4. doi: 10.1021/la904888d.
Two novel low-molecular-weight organogelators (LMOGs) 1 and 2 composed of an anthraquinone unit, a hydrazide group, and long alkyl chains were synthesized. They could form stable gels in wide tested solvents. Chloroalkanes and aromatic solvents tend to result in transparent gels, while alcohol and other solvents yield opaque gels. The FT-IR, PXRD, and (1)H NMR spectral studies revealed that hydrogen bonding and pi-pi interactions were the main driving forces for formation of the gels. Although the hydrazide unit and the anthraquinone group were connected by the sigma-bond, the chloroform gel of 1 could be changed into a red solution upon the addition of anion (F(-), AcO(-), and H(2)PO(4)(-)) due to the disruption of the intermolecular hydrogen-bondings. Moreover, the red color clearly faded at once and the solution regelated upon the addition of methanol. The results indicated that 1 and 2 as smart anion-responsive gel might provide the basis for the development of nonfluid systems for sensing anion with the naked eye.
两种新型的低分子量有机凝胶剂（LMOGs）1 和 2 由蒽醌单元、酰肼基团和长烷基链组成。它们可以在广泛测试的溶剂中形成稳定的凝胶。氯代烷烃和芳香族溶剂往往会导致透明凝胶，而醇和其他溶剂则会产生不透明的凝胶。FT-IR、PXRD 和 1H NMR 光谱研究表明，氢键和 pi-pi 相互作用是形成凝胶的主要驱动力。尽管酰肼单元和蒽醌基团通过 sigma 键连接，但由于分子间氢键的破坏，1 的氯仿凝胶在加入阴离子（F(-)、AcO(-)和 H2PO4(-)）后可以变成红色溶液。此外，加入甲醇后，红色明显褪色，溶液重新结晶。结果表明，1 和 2 作为智能阴离子响应凝胶，可能为开发用于肉眼检测阴离子的非流动体系提供基础。
