Synthesis, Magnetic and Spectral Studies of some Novel Mixed-ligand Chelates of Cobalt(II) involving β-Diketone or β-Diketoesters along with 5,7- Diiodo-8-hydroxyquinolinesulphonamides or 2,3_Dimethyl-1-( 4-methylphenyl)-3- pyrazoline-5-one

Coordination Chemistry Laboratory, Department of P.G. Studies and Research in Chemistry, R.D. University, Jabalpur-482 001

Manuscript received 6 March 1990, revised 5 October 1990, accepted 24 April 1991

β-Diketone and β-diketoesters exhibit keto-enol tauto­merism. They react with metal cations to form chelates¹, which behave as Lewis acids and form adducts with Lewis bases². As the chelates of β-diketoesters resemble to those of β-diketone, a study of the reaction of diaquabis(acetylacetonato)-,diaquabis (methylacetoacetato)- and diaquabis (ethyl­acetoacetato)cobalt(II) with 5,7-diiodo-8-hydro­xyquinoline - 4 - ( m - methoxybenzene) sulphonamide (DIHQMBS), 5, 7 - diiodo 8-hydroxyquinoline-4-(m­ethoxybenzen)sulphonamide (DIHQEBS) and 2,3- dimethyl -1-(4-methylphenyl )- 3-pyrazolin-5-one(DMMPHP) was undertaken on account of biological importance⁸ of these organic compounds.