The crystal structure of the rigid bidentate nitrogen ligand bis[N-(2,6-diisopropylphenyl)imino]acenaphtene (abbr. o,o′-iPr2C6H3-BIAN) and three mixed- ligand coppercomplexes, namely [CuII(AcOH)(o,o′-iPr2C6H3-BIAN)Cl2] (1), [CuII(acac)(AcOH)(o,o′-iPr2C6H3-BIAN)]·(ClO4) (2) (where AcOH=acetic acid and acac=acetylacetonate) and [CuIBr(o,o′-iPr2-p-BrC6H2-BIAN)]2 (3) are reported.