کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1403538 | 1501798 | 2012 | 9 صفحه PDF | دانلود رایگان |
![عکس صفحه اول مقاله: Structural characterization of a new dioxamic acid derivative by experimental (FT-IR, NMR, and X-ray) analyses and theoretical (HF and DFT) investigations Structural characterization of a new dioxamic acid derivative by experimental (FT-IR, NMR, and X-ray) analyses and theoretical (HF and DFT) investigations](/preview/png/1403538.png)
Very few investigations concerning the crystal structure and chemical properties of dioxamic acids have been related in the literature. This work describes the chemical properties of ortho-phenylenebis(oxamic acid) (2) and its new derivative, hydrogeno ortho-phenylenebis(oxamato) benzimidazolium (3) using experimental (FT-IR, NMR, and X-ray single crystal diffraction) and theoretical (HF/3-21G* and B3LYP/6-31G* calculations) methodologies. Compound 2 displays intramolecular hydrogen bonding between the hydrogen of an amide group and the oxygen atom of another amide group present in the structure. Compound 3 was prepared by a newly developed synthetic route involving decomposition of the dioxamic acid in solution without the presence of metallic ions. Thermodynamic calculations indicate a process via two successive hydrolyzes of the amide groups of 2, followed by condensation with formic acid and finally dehydration. The structure of 3 was solved by X-ray single-crystal diffraction and it consists of meso-helical chains stabilized by intra and intermolecular hydrogen bonds and π–π stacking interactions.
► Synthesis of ortho-phenylene(oxamic) acid.
► A new synthetic route involving decomposition of the dioxamic acid.
► Structural characterization of the hydrogeno ortho-phenylenebis(oxamato) benzimidazolium.
► Helical structure stabilized by intra and intermolecular hydrogen bonds and π–π stacking interactions.
Journal: Journal of Molecular Structure - Volume 1016, 30 May 2012, Pages 13–21