Bis[2,4-dibromo-6-(ethyliminomethyl)phenolato-κ2 N,O]cobalt(II)

In the title compound, [Co(C9H8Br2NO)2], the CoII atom, located on a twofold axis, is in a pseudo-tetrahedral environment, with two bidentate 2,4-dibromo-6-(ethyliminomethyl)phenolate Schiff base ligands acting as chelates through their phenolate O and azomethine N atoms. C—H⋯O hydrogen bonds link the complex molecules to form a chain parallel to the b axis.

In the title compound, [Co(C 9 H 8 Br 2 NO) 2 ], the Co II atom, located on a twofold axis, is in a pseudo-tetrahedral environment, with two bidentate 2,4-dibromo-6-(ethyliminomethyl)phenolate Schiff base ligands acting as chelates through their phenolate O and azomethine N atoms. C-HÁ Á ÁO hydrogen bonds link the complex molecules to form a chain parallel to the b axis.

Comment
The Lewis base adducts of the 3,5-dibromosalicylidene group that are derived from the condensation of 3,5-dibromosalicylaldehyde and various primary amine are very interesting in a large number of transition metal complexes (Qiu et al., 2007;Akitsu et al., 2005;Maneiro et al., 2001;Bermejo et al., 1996). Recently, some mononuclear cobalt(II) compounds of Schiff base ligands derived from the condensation of salicylaldehyde with ethyl-, propyl-and butylamine have been structurally characterized (Li et al., 2008;Elerman et al., 1996;Bahron et al., 1994;Groombridge et al., 1992). As an extension of this work, the crystal structure of the title compound, (I), is reported here.
In (I), the Co atoms, located on a two fold axis, have pseudo-tetrahedral coordination environments with two bidentate Schiff base ligands,derived from the condensation of 3,5-dibromosalicylaldehyde and ethylamine, acting as chelates through their phenolate O and azomethine N atoms (Fig. 1). The structure is closely related to the Bis{2-[(E)-benzyliminomethyl]-4,6-dibromophenolato-κ 2 N, O}cobalt(II) compound (Jiang et al., 2008). The C7═N1 bond length of 1.287 (7) Å is similar to that of 1.288 (7) Å observed in the previously reported compound of Schiff base ligand, which was derived from the condensation of salicylaldehyde and isopropylamine (Elerman et al., 1996). The angle between the two O1-Co1-N1 planes of the molecule is equal to 82.80°. All bond lengths are within normal ranges (Allen et al., 1987).
In the crystal structure, the molecules are linked via intermolecular C-H···O hydrogen bonds forming a chain parallel to the b axis (Table 1, Fig. 2).

Refinement
All the H atoms were placed in geometrically idealized positions and constrained to ride on their parent atoms, with C-H distances of 0.93-0.97 Å, and with U iso (H) = 1.2U eq (carrier) or 1.5U eq (methyl groups).