A new supramolecular compound of chrome(III): Synthesis, spectroscopic characterization, X-ray crystal structure, DFT, and solution studies

作者：Eshtiagh-Hosseini, Hossein^*; Yousefi, Zakieh; Mirzaei, Masoud; Chen, Ya-Guang; Beyramabadi, S. Ali; Shokrollahi, Ardeshir; Aghaei, Roghayyeh

来源：Journal of Molecular Structure, 2010, 973(1-3): 1-8.

DOI：10.1016/j.molstruc.2010.02.054

• Chrome
• Pyridine-2,6-dicarboxylic acid
• 2-Aminopyrimidine
• Crystal structure
• Solution studies
• DFT

A new supramolecular compound of Cr(III) atom was synthesized and characterized by using elemental analysis, FTIR spectroscopy, UV-vis, and single crystal X-ray diffraction method. The chemical formula and space group of the resulting compound is (2-apymH)[Cr(pydc)(2)]center dot 2H(2)O (1) (pydc = 2,6-pyridinedicarboxylate, 2-apym = 2-aminopyrimidine) and P2(1)/c where the final R value is 0.0157 for 3896 reflections collected. The [Cr(pydc)(2)](-) anions and the (2-apymH)(+) moiety form a three-dimensional solid state structure by a variety of noncovalent interactions such as ion pairing and hydrogen bonds interactions. On the basis of crystallographic data, it can be seen that Cr(III) atom is six-coordinated by two (pydc)(2-) groups. With respect to bond lengths and angles, it is observed that coordination sphere around Cr(III) atom is a distorted octahedral. Furthermore, DFT calculation and solution study have been completely performed on 1 where corresponding data showed that obtained results from DFT and solution studies have good agreement with X-ray crystallography results. The optimized geometry confirms that the C-O-(bonded) bond length of (pydc)(2-) ligand in its complex form has been increased compared with the free ligand. The evidence shows that C-O-(bonded) is weakened upon formation of complex, while C=O-(free) converted to double bond. Anionic complex possesses 90 occupied molecular orbitals and 3 half-occupied ones (91- 93). A comparison between the stoichiometry of the crystalline complex in pydcH(2)-2-apym-Cr system and the results obtained from solution studies clearly revealed that the CrL(2)QH is the most abundant species existing in aqueous solution possesses a stoichiometry similar to that of the complex which was obtained in the solid state.

• 出版日期2010-6-2
• 单位东北师范大学