The complex of cobalt(II) chloride with bi-1, 1'-(3, 3-dimethyl-3, 4-dihydroisoquinoline) (L), [CoLCl2] ( I ), is synthesized and studied by X-ray diffraction, electronic spectroscopy, and IR spectroscopy. In the structure of complex I , ligand L performs a bidentate-chelating function, adding to the cobalt atom through the nitrogen atoms. The coordination polyhedron of the cobalt atom is a tetrahedron (2N, 2Cl) with ordinary Co-N (2.00(1)-2.07(1) Å) and Co-Cl (2.216(6)-2.226(6) Å) bond lengths. The noncentrosymmetric orthorhombic unit cell of crystal I contains two independent molecules of the complex (1 and 1') joined by C-H=Cl hydrogen bonds into a pseudocentrosymmetric dimer. Ligands Lc and L'c exist in the same cisoid isomeric form (torsion angle N(1)-C(1)-C(12)-N(2) is 19.2° in Lc and 26.6° in L'c). © Pleiades Publishing, Inc., 2009.