(Carbonato-κ2 O,O′)bis­(di-2-pyridyl­amine-κ2 N,N′)cobalt(III) bromide

Agnieszka Czapik; Christos Papadopoulos; Maria Lalia-Kantouri; Maria Gdaniec

doi:10.1107/S1600536811008051

. 2011 Mar 9;67(Pt 4):m414–m415. doi: 10.1107/S1600536811008051

(Carbonato-κ² O,O′)bis(di-2-pyridylamine-κ² N,N′)cobalt(III) bromide

Agnieszka Czapik ^a, Christos Papadopoulos ^b, Maria Lalia-Kantouri ^b, Maria Gdaniec ^a,^*

PMCID: PMC3100002 PMID: 21753946

Abstract

In the title compound, [Co(CO₃)(C₁₀H₉N₃)₂]Br, a distorted octahedral coordination of the Co^III atom is completed by four N atoms of the two chelating di-2-pyridylamine ligands and two O atoms of the chelating carbonate anion. The di-2-pyridylamine ligands are nonplanar and the dihedral angles between the 2-pyridyl groups are 29.11 (9) and 37.15 (12)°. The coordination cation, which has approximate C ₂ symmetry, is connected to the bromide ion via an N—H⋯Br⁻ hydrogen bond. The ionic pair thus formed is further assembled into a dimer via N—H⋯O interactions about an inversion centre. A set of weaker C—H⋯O and C—H⋯Br⁻ interactions connect the dimers into a three-dimensional network.

Related literature

For the crystal structure of the isostructural [bis(di-2-pyridylamine-κ² N,N′)](carbonato-κ² O,O′)cobalt(III) nitrate, see: Castillo et al. (2011 ▶). For the crystal structure of the perchlorate salt, see: Williams et al. (1987 ▶).

Experimental

Crystal data

[Co(CO₃)(C₁₀H₉N₃)₂]Br
M _r = 541.25
Monoclinic,
a = 16.9605 (3) Å
b = 7.4322 (1) Å
c = 17.2590 (4) Å
β = 105.839 (2)°
V = 2092.96 (7) Å³
Z = 4
Mo Kα radiation
μ = 2.77 mm⁻¹
T = 130 K
0.30 × 0.15 × 0.05 mm

Data collection

Oxford Diffraction Xcalibur E diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent Technologies, 2010 ▶) T _min = 0.710, T _max = 0.874
29846 measured reflections
4277 independent reflections
3386 reflections with I > 2σ(I)
R _int = 0.064

Refinement

R[F ² > 2σ(F ²)] = 0.037
wR(F ²) = 0.080
S = 1.01
4277 reflections
289 parameters
H-atom parameters constrained
Δρ_max = 0.79 e Å⁻³
Δρ_min = −0.50 e Å⁻³

Data collection: CrysAlis PRO (Agilent Technologies, 2010 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶) and Mercury (Macrae et al., 2006 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811008051/su2260sup1.cif

e-67-0m414-sup1.cif^{(21.2KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811008051/su2260Isup2.hkl

e-67-0m414-Isup2.hkl^{(205.4KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Selected bond lengths (Å).

Co1—O2	1.901 (2)
Co1—O1	1.904 (2)
Co1—N9B	1.919 (2)
Co1—N1A	1.923 (2)
Co1—N1B	1.925 (2)
Co1—N9A	1.933 (2)

Open in a new tab

Table 2. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N7A—H7A⋯O2ⁱ	0.86	2.08	2.876 (3)	154
N7B—H7B⋯Br1	0.86	2.49	3.327 (2)	164
C10B—H10B⋯O3ⁱⁱ	0.95	2.34	3.225 (4)	155
C5A—H5A⋯O1ⁱⁱⁱ	0.95	2.44	3.265 (4)	146
C13A—H13A⋯O3ⁱ	0.95	2.43	3.316 (4)	156
C13B—H13B⋯Br1	0.95	2.83	3.623 (3)	142
C5B—H5B⋯Br1^iv	0.95	2.86	3.741 (3)	155
C4B—H4B⋯Br1^v	0.95	2.89	3.657 (3)	139

Open in a new tab

Symmetry codes: (i) Inline graphic ; (ii) ; (iii) ; (iv) ; (v) .

supplementary crystallographic information

Comment

The title compound (Fig. 1) was obtained as a byproduct in the preparation of [Co(Hdpa)₂(apo)]Br from CoBr₂, where apo is 2-acetylphenolate ion and Hdpa is di-2-pyridylamine. The chelating carbonate ligand in the coordination cation was identified from its geometrical parameters, namely the two bonds of 1.325 (4) and 1.341 (4) Å indicated single C—O bonds and the bond length of 1.183 (4) Å pointed to a C=O bond. The presence of the carbonate anion in the studied compound concurred with the +3 oxidation state of the cobalt atom. The Co^III atom shows a distorted octahedral coordination that is completed by four N atoms of the two chelating di-2-pyridylamine ligands and two O atoms of the chelating carbonate anion (Table 1). The bidentate Hdpa ligands chelate the Co^III atom to form two six-membered rings with the N1—Co1—N9 bite angles of 90.42 (10) and 88.48 (10)°, in ligand A and B respectively. The diimine ligands are non-planar with the N(py)—C—N(H)—C torsion angles of 28.1 (4) and -27.6 (4)° in the A ligand and 28.0 (4) and -33.5 (4)° in the B Hdpa ligand.

The coordination cation has approximate C₂ symmetry with a pseudo-twofold axis passing through atoms O3, C1 and Co1. It binds one Br^- anion via a N—H···Br^- hydrogen bond and the ionic pair thus formed assembles into a dimer, via N—H···O hydrogen bonds (Fig. 2, Table 2), centered about an inversion center. These dimers are further connected via a C10B—H10B···O3(x, y - 1, z) interaction into chains extended along [010] and the chains are joined via a set of C—H···O and C—H···Br^- interactions into a three-dimensional network (Table 2).

Interesingly, similar interactions between the coordination cation and the anion, and the formation of dimers of the ionic pairs, was also observed in the nitrate and perchlorate salts of the same cation (Castillo et al., 2011; Williams et al., 1987). Moreover, the crystals of the nitrate salt and the title bromide salt are to a large extent isostructural.

Experimental

2 mmol (0.342 g) of di-2-pyridylamine (Hdpam), dissolved in a small amount of EtOH, was added to a solution of 1 mmol (0.238 g) of CoBr₂.H₂O in 5 ml of EtOH and the mixture was stirred for 30 min. Then, to this mixture was added dropwise an ethanolic solution containing 1 mmol (0.136 g) of 2-hydroxyacetophenone (Hapo) and 1 mmol of CH₃ONa. The solution was stirred at room temperature under an argon atmosphere for 2 h or refluxed with continuous stirring. Two types of crystals precipitated from the solution. The main product, in the form of small crystals of light orange color, was identified as the mixed-ligand Co^II complex [Co(dpamH)₂(apo)]Br (mean yield 62%). The side-product, in the form of large dark-red crystals, was identified as the Co^IIIcomplex, [Co(dpamH)₂(CO₃)]Br. When the reaction between CoBr₂ and Hdpam was repeated in air the title compound, [Co(dpamH)₂(CO₃)]Br, was obtained as the main product.