Synthesis and properties of some β-diketimines derived from acetylacetone, and their metal complexes

The synthesis of a number of diketimine ligands of structure 1 is reported. These give bis-bidentate chelates of type 2 with Cu(II), Ni(II), and Co(II). Optical spectra, magnetic moments and, in a number of instances, solution molecular weights are recorded for these complexes. On the basis of these, it is concluded that the complexes unsubstituted on nitrogen, adopt a square planar stereochemistry in contrast to the others which are all pseudotetrahedral.