Synthesis and X-ray Crystallographic and Spectroscopic Study of Dichlorobis{spiro[cyclopentane-1′,-3-(1-(4′,4′-dimethyl- 2′,6′-cyclohexanedion-1′-ylidene)-1,2,3,4- tetrahydroisoquinoline-O)]}cobalt(II)

The new complex [CoL1 2Cl2] (I), where L1 is spiro[cyclopentane-1′,3-(1-(4′,4′-dimethyl-2′,6′- cyclohexanedion-1′-ylidene)-1,2,3,4-tetrahydroisoquinoline)], was synthesized. The X-ray crystal structure of I was determined (3062 independent reflections, R = 0.0406, a = 26.690(5) Å, b = 12.959(3) Å, c = 23.339(5) Å, β= 90.65(3)°, space group C2/c, Z- 8). Interatomic distances, bonds angles, and conformations of the molecule of ligand L1 in complex I are as a whole close to those of 3,3-dimethyl- (L2) and spiro{cyclohexane-1',3- (L3) 1-(4′,4′-dimethyl-2′,6′cyclohexanedion-1′-ylidene) -1,2,3,4-tetrahydroisoquinolines in the previously studied complexes [CuL2Cl2]n (II) and [CuL3Cl2]n · nH2O (III). The occurrence of the Co(II) atom instead of the Cu(II) atom in I leads to changes in the ligand coordination mode: L1 is monodentately coordinated to the Co(II) atom via one of the oxygen atoms of the cyclohexanedione fragment. The M : L molar ratio in I differs from that in II and III (1 : 2 in I and 1 : 1 in II and III), although the conditions of the synthesis are the same (metal : ligand ratio, acetone, 20°C). This complex is characterized by IR and electronic absorption spectroscopy data.