Dinuclear oxidovanadium(V) complexes incorporating N, N, O, O coordinating ligands: Synthesis, structure, spectral, DFT and TDDFT study

详细信息    查看全文

• 作者：Pallab Mondal ; Amar Hens ; Kajal Krishna Rajak ; ^{kkrajak@chemistry.jdvu.ac.in} ; ^{kajalrajak@rediffmail.com}
• 关键词：Oxidovanadium(V) complexes ; X-ray structure ; Spectral study ; DFT studies
• 刊名：Polyhedron
• 出版年：2013
• 出版时间：30 April, 2013
• 年：2013
• 卷：54
• 期：Complete
• 页码：228-236
• 全文大小：875 K

文摘

Dinuclear (V^VV^V) oxidovanadates of general formula [V₂O₃(L)₂] have been synthesized in excellent yields by reacting bis(acetylacetonato)oxidovanadium(IV) with H₂L in a 1:1 ratio in acetonitrile in air. Here L^2? is the deprotonated form of 2-[((2-hydroxypropan-2-yl)(pyridin-2-ylmethyl)amino)methyl]phenol (H₂L¹), 2-[((1-hydroxy-2-methylpropyl)(pyridin-2-ylmethyl)amino)methyl]phenol (H₂L²) and 2-[((1-hydroxy-3-methylbutyl)(pyridin-2-ylmethyl)amino)methyl]phenol (H₂L³). X-ray crystallographic study for the complex 1 reveals that the relative disposition of the two VO groups in [V₂O₃(L¹)₂] is almost cis, the O6V1¡ªV2O7 torsion angle being 42.9(2)¡ã. Low V^V/V^IV reduction potentials (?0.50 V versus SCE) are indicative of the considerable VO³⁺ stabilization due to alkoxide coordination. The gas-phase geometry optimization and the electronic structures of [V₂O₃(L¹)₂], 1; [V₂O₃(L²)₂], 2 and [V₂O₃(L³)₂], 3 have been investigated with the framework of density functional theory. The absorption spectra of the complexes and the CD spectra for 2 and 3 are calculated by time dependent density functional theory (TDDFT) using conductor like polarizable continuum model (CPCM). DFT calculation shows a good agreement to the experimental ground state IR and NMR value.