Related Experiment Videos
Cis,cis,cis-1,2,4,5-cyclohexanetetracarboxylic acid and its dianhydride
Akira Uchida1, Masatoshi Hasegawa, Hiroshi Manami
1Department of Biomolecular Science, Faculty of Science, Toho University, Miyama 2-2-1, Funabashi, Chiba 274-8510, Japan. auchida@biomol.sci.toho-u.ac.jp
Summary
This study details the crystal structure of cis,cis,cis-1,2,4,5-cyclohexanetetracarboxylic acid and its dianhydride derivative. It reveals specific conformations and hydrogen bonding patterns, offering insights into molecular packing and reactivity.
Area of Science:
- Crystallography
- Organic Chemistry
- Supramolecular Chemistry
Background:
- The study investigates the solid-state structures of cis,cis,cis-1,2,4,5-cyclohexanetetracarboxylic acid (I) and its dianhydride derivative (II).
- Understanding molecular conformation and intermolecular interactions is crucial for predicting material properties and reactivity.
Purpose of the Study:
- To elucidate the crystal structure and hydrogen bonding network of cis,cis,cis-1,2,4,5-cyclohexanetetracarboxylic acid (I).
- To characterize the structure of the derived cis,cis,cis-1,2:4,5-cyclohexanetetracarboxylic dianhydride (II), including its conformation and the relationship between anhydro rings.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the molecular and crystal structures of both compounds.
- Analysis of hydrogen bond motifs and their propagation within the crystal lattice.
Main Results:
- Compound (I) exhibits a chair conformation with a mirror plane, featuring two independent hydrogen bonds forming various ring motifs (R(2)(2)(14), R(2)(2)(16), R(4)(4)(16)).
- Hydrogen bond propagation along crystallographic axes generates specific chain structures (C(2)(2)(16), C(2)(2)(7)).
- Compound (II) was synthesized from (I) and displays a boat conformation with a dihedral angle of 117.5(1)° between its two anhydro rings.
Conclusions:
- The study provides detailed structural information on cyclohexanetetracarboxylic acid and its dianhydride, highlighting conformational flexibility and the role of hydrogen bonding in crystal engineering.
- The observed conformations and hydrogen bonding patterns offer fundamental insights into the solid-state behavior of these polycarboxylic acids and their derivatives.