1,4,8,11-Tetraazoniacyclotetradecane tetrachloridocobaltate(II) dichloride

The asymmetric unit of the title compound, (C10H28N4)[CoCl4]Cl2, contains two half-molecules of the macrocycle, which are both completed by crystallographic inversion symmetry. In the dianion, the Co2+ cation is tetrahedrally coordinated by four Cl atoms; the Co—Cl bond lengths correlate with the number of hydrogen bonds that the chloride ions accept. The crystal cohesion is supported by electrostatic interactions which, together with numerous N—H⋯Cl, N—H⋯(Cl,Cl) and C—H⋯Cl hydrogen bonds, lead to a three-dimensional network.

The asymmetric unit of the title compound, (C 10 H 28 N 4 )- [CoCl 4 ]Cl 2 , contains two half-molecules of the macrocycle, which are both completed by crystallographic inversion symmetry. In the dianion, the Co 2+ cation is tetrahedrally coordinated by four Cl atoms; the Co-Cl bond lengths correlate with the number of hydrogen bonds that the chloride ions accept. The crystal cohesion is supported by electrostatic interactions which, together with numerous N-HÁ Á ÁCl, N-HÁ Á Á(Cl,Cl) and C-HÁ Á ÁCl hydrogen bonds, lead to a threedimensional network.
Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB5513).

Comment
The rational design and synthesis of organic-inorganic hybrid materials have attracted an increasing interest in recent years not only from a structural point of view, but also due to their potential applications in different areas such as catalysis, medicine, electrical conductivity, magnetism and photochemistry (e.g. Bu et al., 2001).
A large number of transition metal when associated to organic molecule which presents potential sites of the hydrogen bonding interactions, exhibit interesting one-(1-D), two-(2-D), and three-dimensional (3-D) structures. These organic molecules may be present different and interesting properties which can profoundly influence the structures of inorganic component in the resultant hybrid material. Such organic-inorganic hybrid materials can combine appropriate characteristics of each component to produce novel structural types, as well as new properties arising from the interplay of the two components (Mitzi et al., 1999).
The asymmetric unit of the [CoCl 4 ](C 10 H 28 N 4 ),2Cl, (I). contains one tetrachlorocobalt anion, one organic cation and two chloride anion as shown in Fig. 1. The cohesion and the stability between these different components are assured by the network hydrogen bonding of type (N-H···Cl). However, the energetic of N-H···Cl-M (M = metal) hydrogen bonds and their possible roles in supramolecular chemistry have only been recently described in details (Brammer et al., 2002).
The Co 2+ entity is tetrahedrally coordinated to four chloride atoms as shown in Figure 2. The distortion from the ideal geometry is small. This situation is also observed in others compounds which contain CoCl 4 2entity as an anion (Adamski et al., 2009). Examination of the CoCl 4 2geometry shows two types of Co-Cl distances. The largest ones 2.3170 (8) Å, 2.2963 (7) Å and 2.2950 (9) Å, while the smallest one is 2.2609 (8) Å. The average values of the Co-Cl distances and Cl-Co-Cl angles are 2.2923 Å and 109.52°, respectively. These geometrical features have also been noticed in others crystal structure (Boyd et al., 2007); (Hashizume et al., 1999).
The differences in the Co-Cl bond lengths correlate with the number of hydrogen bonds accepted by the Cl atom: Co-Cl4 bond is the longest (2.3170 (8)  which was completely dissolved by adding an aqueous solution of HCl until it disappeared. The obtained solution was slowly evaporated at room temperature for several days until the formation of blue prisms of (I). The synthesis is reproducible and crystals obtained in this way are stable for a long time under normal conditions of temperature and humidity.