Synthesis and structural studies on di-oxovanadium(V) complexes of N(4)-substituted pyrazole based thiosemicarbazones
作者:Arijit Hazra、Anil Kumar Barik、Sachindranath Pal、Samik Gupta、Somnath Roy、Ray J. Butcher、Shie-Ming Peng、G.H. Lee、Susanta Kumar Kar
DOI:10.1016/j.poly.2006.09.005
日期:2007.3
Three mononuclear cis-dioxovanadium(V) complexes of tridentate thiosemicarbazones derived from 5-methyl-3-formylpyrazole (MPA) and N(4) -methyl/ethyl/dimethyl thiosemicarbazide have been synthesized and characterized. Single crystal X-ray analyses were performed with [VO2L1] (1), [VO2L2] (2) and [VO2L3] (3), where L-1, L-2 and L-3 denote the [1 + 1] thiosemicarbazone mono-anions derived from MPA and N(4)-substituted methyl/ethyl/dimethyl thiosemicarbazide respectively. In all the complexes the vanadium atom is in a distorted square pyramidal geometry with a N2SO2 chromophore. The interesting finding in the work is that in complexes 1 and 2, the thioimine nitrogen unusually participates in coordination whereas in 3 it is the azomethine nitrogen (quite usual) which is involved in the coordination process. (c) 2006 Elsevier Ltd. All rights reserved.