Complexes with NSO and N2S2 Donor Ligands. Cobalt (II), Cobalt(III) and Nickel(II) Complexes Of 2,4-bis (2′-Mercapto-Phenylimino)Pentane, 2-(2-Mercaptophenyl)imino-4-pentanone and 2-(2-Mercaptophenyl)-salicylaldimine and Their Reactions

Reactions of acetylacetone and salicylaldehyde with 2-aminobenzenethiol yielded the benzothiazolines Hopatz and Hopbtz, respectively, rather than the corresponding Schiff bases. The reactions of benzothiazolines with Co(OAc)2.4H2O,Co(NO3)2.6H2O, Co(acac)2.2H2O and Ni(acac)2.H2O afforded the corresponding metal Schiff base chelates. Under suitable metal template reaction conditions two moles of 2-aminobenzenethiol have been found to condense with one mole of acetylacetone (in the diketo form) leading to the synthesis of Co(II) and Co(III) complexes of a quadridentate N2S2 donor ligand. The reaction of [CoII (pdmpi)]H2O {H2pdmpi = 2,4-bis (2′-tnercaptophenylimino) pentane} synthesized in this study, with Cd(NO3)2.4H2O and Mn(CO)5Br afforded [{coII(pdmpi)}2 Cd](NO3)2and [CoII (pdmpi) Mn(CO) 3Br] where CoII (pdmpi) functions as a bldentate S,S-donor metallo-ligand. The cobalt(II) complex CoII (pdmpi)H2O smoothly reacts with bifunctional alkylating agents like 1,2-dibromoethane to form the inacrocyclic complex {S,S ′ -ethylene-2,4-bis (2 ′-mercaptopbenylimiao)-pentane} cobalt (II) dibromide, [Co(epdmpi)] Br2, as a result of the alkylation of the two coordinated mercaptide groups of the complex. The complexes were characterised by elemental analyses, magnetic susceptibility and molar conductance values, molecular weights (Rast's method and osmometry) and spectroscopic (UV-visible, IR) data.