Abstract The characterization and improved syntheses of complexes of the type [Co(Mentrien)Cl2]Cl are reported. The ligands are 5R- and 5S-Metrien, 2S,9S-Me2trien, 2S,5R,9S- and 2S,5S,9S-Me3-trien, which can be represented by the general formula H2N-CHR-CH2-NH-CH2-CHR′-NH-CH2-CHR-NH2 (R and R′ = H or CH3). Proton nmr, ir and uv-visible spectra, and ORD and CD spectra were obtained for the dichloro complexes. Assignments of absolute configuration were made on the basis of the ORD and CD curves and assignments in the literature.