Chloridobis(ethane-1,2-diamine)(4-methylaniline)cobalt(III) dichloride monohydrate

In the title compound, [CoCl(C2H8N2)2(C7H9N)]Cl2·H2O, the CoIII ion has a distorted octahedral coordination environment and is surrounded by four N atoms in an equatorial plane, with the other N and Cl atoms occupying the axial positions. The crystal packing is stabilized by N—H⋯O, N—H⋯Cl and O—H⋯Cl interactions.

In the title compound, [CoCl(C 2 H 8 N 2 ) 2 (C 7 H 9 N)]Cl 2 ÁH 2 O, the Co III ion has a distorted octahedral coordination environment and is surrounded by four N atoms in an equatorial plane, with the other N and Cl atoms occupying the axial positions. The crystal packing is stabilized by N-HÁ Á ÁO, N-HÁ Á ÁCl and O-HÁ Á ÁCl interactions.

S1. Comment
Mixed ligand cobalt(III) complexes find potential applications in the fields of antitumor, antibacterial, antimicrobial, radiosenzitation and cytotoxicity activities (Sayed et al., 1992;Teicher et al., 1990;Arslan et al., 2009;Delehanty et al., 2008). Cobalt is an essential and integral component of vitamin B 12 , therefore it is physiologically found in most tissues.
Complexes of cobalt are useful for nutritional supplementation to provide cobalt in a form which effectively increases the bioavailability, for instance, vitamin B 12 by microorganisms present in the gut. In addition, cobalt(III) complexes are known for electron transfer and ligand substitution reactions, which find applications in chemical and biological systems.
Against this background and to ascertain the molecular conformation, the structure determination of the title compound has been carried out.
The crystal packing is controlled by N-H···O, N-H···Cl and O-H···Cl interactions.

S2. Experimental
The complex was synthesized using dichlorobis(1,2-diamino ethane) cobalt(III) chloride by the reported method (Bailer & Clapp, 1945). A paste was prepared in a mortar with 2 g of trans-[Co III (en) 2 Cl 2 ]Cl crystals in 3-4 drops of deionized water. To the solid mass, about 2.5 g of 4-methyl aniline dissolved in ethanol was added in drops for 20 min. The grinding was continued for half an hour and the color was found to change from dull green to red. The reaction mixture was set aside until no further change was observed and the product was allowed to stand overnight. Finally, the solid was washed with 3-4 times using pure ethanol. The final complex was dissolved in 5-10 ml of deionized water pre-heated to 70°C. The cobalt(III) complex was recrystallized out on addition of few drops of hot conc. HCl and 2 ml of water and cooled. The crystals were filtered, washed with ethanol and dried over vacuum.

S3. Refinement
Nitrogen and Oxygen H atoms were freely refined. Other H atoms were positioned geometrically (C-H = 0.93-0.97 Å) and allowed to ride on their parent atoms, with 1.5U eq (C) for methyl H and 1.2 U eq (C) for other H atoms.   The crystal packing of the molecules viewed down the a-axis. H atoms not involved in hydrogen bonding have been omitted for clarity. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.