Studies on oxovanadium(IV) and dioxouranium(VI) complexes of Schiff bases derived from pyrazine-2-carboxylic acid hydrazine and pyrazine-2,3-dicarboxylic acid dihydrazide with salicylaldehyde

Department of Chemistry, University of Kalyani, Kalyani-741 235, India E-mail : rakesh_ganguly@yahoo.com Fax : 91-33-5828282 Manuscript received 6 September 2000, revised 16 March 2001, accepted 12 May 2001 Oxovanadium(IV) and dioxouranium(VI) complexes of Schiff bases (L and L') derived respectively from pyrazine-2-carboxylic acid hydrazide and pyrazine-2,3-dicarboxylic acid dihydrazide with salicylaldehyde have been prepared. The Schiff bases behave as ter-dentate O (enolic) N (azomethine) O (phenolic) donors in their fully deprotonated complexes; bidentate O (keto) N (azomethine) donors in the hydroxo complexes and bidentate O (enolic) N (azomethine) donor in the partially deprotonated complex, (UO2)2(acac)2(L'-2H)