Two rare copper complexes, a tri-alkene adduct [Cu(ttt-cdt)(FSbF5)] and a non-classical carbon monoxide complex [Cu(ttt-cdt)(CO)][SbF6] with a high CO stretching frequency (CO = 2160 cm−1), have been isolated using trans,trans,trans-1,5,9-cyclododecatriene (ttt-cdt) ligand.