Mono- and poly-nuclear complexes of copper(II) with linear and branched bis-β-diketonato ligands

The coordination of copper(II) with tetradentate bis-β-diketonato ligand (L2) has been systematically investigated. Two series of dinegative ligands were considered: one with terminally linked connecting chains, CH3COCHCOCH2(CH2)nCH2COCHCOCH3, (linear ligands; n = 4, 6, 8) and the other with centrally linked chains, (CH3CO)2C(CH2)innC(COCH3)2 (branched ligands; n = 6, 8, 10, 12). All complexes contained square planar, magnetically dilute [CuO4] coordination entities, similar to those formed by mono-β-diketonates. In the solid complexes of the linear and short-chain (n = 6, 8) branched ligands, the [CuO4] entities were linked to form polymeric species, whereas monomeric species (for n = 12) or a monomer-polymer mixture (for n = 10) was obtained.