Mixed ligand complexes of β-diketones of the form [Cu(tfa)(bzac)], [Cu(tfa)(acac)] and their 2,2′-bipyridine (bipy) and 1,10-phenanthroline (phen) adducts have been synthesized and characterized by metal analysis, electronic, infrared spectra and magnetic susceptibility measurements. Infrared spectra showed the shifting of bands at 1698 and 1588 cm-1 to lower frequency in the adducts. The d-d spectral band positions suggest square planar and octahedral geometries for the copper(II) complexes and their various adducts respectively. The magnetic moments of the copper(II) complexes and their various adducts suggest that they are magnetically dilute compounds. The copper(II) complexes exhibited broad spectrum of antimicrobial activity against the Gram-negative, Gram-positive and fungi tested generally at 100-25 mg/mL concentrations in-vitro. [Cu(tfa)(bzac)] was most outstanding in this regard.