Transition Metal Complexes of Derivatized Chiral Dihydro-1,2,4-triazin-6-ones. Template Synthesis of Nickel(II) Tetraaza-(4N-M) Complexes Incorporating the Triazinone Moiety

Template reactions of (L)-3-acetyl-5-methyl-1-phenyl-4,5-dihydro-1,2,4-triazine-6- one (8a) or (L)-3-acetyl-5-benzyl-1-phenyl-4,5-dihydro-1,2,4-triazine-6-one (8b) with nickel(II) acetate in the presence of a suitable diamine such as: 1,3-diaminopropane, o-phenylenediamine, or ethylenediamine afforded square planar tetraaza nickel(II) complexes of the type 4N-M (Scheme 4). Single crystal X-ray structural analysis of one of the complexes (9b) revealed square planar geometry around the nickel ion and symmetrical coordination of the triazinone moieties. The complexes were characterized by elemental analyses, magnetic measurements, and electrical conductivities.