Twin-Tapered Molecules Containing Bi-dihydrazine Units: Self-Assembly through Intermolecular Quadruple Hydrogen Bonding and Liquid Crystalline Behavior

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• 作者：Songnan Qu ; Fan Li ; Haitao Wang ; Binglian Bai ; Chunyan Xu ; Lianjiu Zhao ; Beihong Long ; Min Li
• 刊名：Chemistry of Materials
• 出版年：2007
• 出版时间：October 2, 2007
• 年：2007
• 卷：19
• 期：20
• 页码：4839 - 4846
• 全文大小：264K
• 年卷期：v.19,no.20(October 2, 2007)
• ISSN：1520-5002

文摘

We report on the synthesis and self-assembly of a new series of twin-tapered dihydrazide derivatives,oxalyl acid N',N'-di(3,4,5-trialkoxybenzoyl)-hydrazide (FH-Tn). Results from ¹H NMR diluting experimentsin chloroform and temperature-dependent ¹H NMR spectroscopy revealed that molecules exhibited aconformational change at concentrations lower than 255 M, e.g., from intramolecularly H-bonded six-membered rings to five-membered rings in the monomer state upon concentrating. Measurements of ¹HNMR diluting experiment, FTIR spectroscopy, and mass spectroscopy revealed that the FH-Tn self-assembled into supramolecular chains either in chloroform at concentrations greater than 255 M or inbulk through intermolecular quadruple H-bonding. On the basis of the results of DSC, polarized opticalmicroscopy, and wide-angle X-ray diffraction (WAXD), we assigned enantiotropic hexagonal and unknowncolumnar phases to FH-Tn (n = 6, 7, 8, 10).