metal-organic compounds
cis-Bromidobis(ethylene-1,2-diamine)(2-methylpropan-1-amine)cobalt(III) dibromide
aDepartment of Chemistry, BWDA Arts and Science College, Tindivanam 604 304, India, bDepartment of Chemistry, Pondicherry University, Pondicherry 605 014, India, cP. G. & Research Department of Physics, A. A. Govt. Arts College, Villupuram, India, and dDepartment of Physics, Thiruvalluvar University College of Arts and Science, Thiruvennainallur 607 203, India
*Correspondence e-mail: e.govindan84@gmail.com
In the title compound, [CoBr(C2H8N2)2(C4H11N)]Br2, the cobalt(III) ion has a distorted octahedral coordination environment and is ligated by three N atoms and a bromine ion in the equatorial plane, and by two N atoms occupying the axial positions. In the crystal, the complex cation and the two Br− counter-anions are linked by N—H⋯Br hydrogen bonds, forming a supramolecular framework.
Keywords: crystal structure; cobalt(III); dibromide; N—H⋯Br hydrogen bonding.
CCDC reference: 1867356
Structure description
In recent years, considerable effort has been dedicated to the design and synthesis of supramolecular architectures of coordination complexes (Lehn, 1995; Khlobystov et al., 2001). The primary reason for the interest in such complexes is their new and versatile topologies and potential applications in functional materials (Desiraju, 1995; Seo et al., 2000). The interaction of transition metal polyamine complexes of cobalt(III) with DNA has received considerable attention in recent years. Using mixed-ligand complexes, it is possible to systematically vary parameters of interest by changing the properties of the interacting units either by the use of suitable substituents or by simply changing the nature of the ancillary ligand. In addition, cobalt(III) complexes have sustained a high level of attention because of their relevance in various redox processes in biological systems and their antitumor, anthelmintic, antiparasitic, antibiotic and antimicrobial activities, as well as their multiple applications in the fields of medicine and drug delivery (Chang et al., 2010). Against this background and to ascertain the molecular structure and configuration of the title compound, the determination has been carried out.
The molecular structure of the title compound is shown in Fig. 1. It is composed of a cobalt(III) complex with the metal atom being coordinated by two ethylene-1,2-diamine (en) and one 2-methylpropan-1-amine ligands, and a Br− ion. The metal cation has a distorted hexagonal coordination sphere, being ligated to three N atoms, N2 and N3 of two en ligands and atom N5 of the 3-methylbutan-1-amine ligand, and a bromine atom (Br1) in the equatorial plane. The remaining en N atoms, N1 and N4, occupy the axial positions. This arrangement is very similar to that observed for cis-chlorido(ethylamine)bis(ethylene-1,2-diamine)cobalt(III) dichloride (Maheshwaran et al., 2013). In the title complex cation, the Co—Nen bond lengths vary from 1.950 (4) to 1.963 (4) Å, while the Co—N5 bond length involving the 2-methylpropan-1-amine ligand is 1.998 (4) Å and the Co1—Br1 bond length is 2.4019 (11) Å. These bond lengths are comparable to the values reported in the literature for similar compounds (Lee et al., 2007; Ramesh et al., 2008; Anbalagan et al., 2009; Ravichandran et al., 2009). Both five-membered chelate rings, which are cis to each other, have twisted conformations on the C—C (C1—C2 and C3—C4) bonds and their mean planes are inclined to each other by 79.4 (3)°.
In the crystal, the cations and anions are linked by a number of N—H⋯Br hydrogen bonds forming a supramolecular framework (Table 1, Fig. 2), with small cavities as shown in Fig. 3. No residual electron density was observed in these regions in the final difference-Fourier map.
Synthesis and crystallization
A suspension of 2 g of trans-[CoIII(ethylene-1,2-diamine)2Br2]Br was made into a paste using 3–4 drops of water. To this solid mass, ca 2 ml of 2-methylpropan-1-amine was added drop wise over 20 min and mixed well. Grinding was continued until the colour becomes 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 ethanol then dissolved in 5–10 ml of water and pre-heated to 343 K. It was allowed to crystallize using hot acidified water (yield 0.85 g). The crystals were filtered, washed with ethanol and dried under vacuum. X-ray quality crystals were obtained by repeated recrystallization from hot acidified distilled water giving finally pink plate-like crystals.
Refinement
Crystal data, data collection and structure .
details are summarized in Table 2
|
Structural data
CCDC reference: 1867356
https://doi.org/10.1107/S2414314618012907/su4167sup1.cif
contains datablocks I, Global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618012907/su4167Isup2.hkl
Data collection: APEX2 (Bruker, 2008); cell
SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009) and publCIF (Westrip, 2010).[CoBr(C2H8N2)2(C4H11N)]Br2 | Z = 2 |
Mr = 492.00 | F(000) = 484 |
Triclinic, P1 | Dx = 1.829 Mg m−3 |
a = 7.3567 (7) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 11.6172 (19) Å | Cell parameters from 4095 reflections |
c = 11.7805 (15) Å | θ = 2.9–29.3° |
α = 112.084 (13)° | µ = 7.66 mm−1 |
β = 99.118 (9)° | T = 293 K |
γ = 99.431 (10)° | Plate, pink |
V = 893.3 (2) Å3 | 0.23 × 0.17 × 0.11 mm |
Bruker SMART APEXII area-detector diffractometer | 1911 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.052 |
ω and φ scans | θmax = 25.5°, θmin = 2.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2008) | h = −7→8 |
Tmin = 0.165, Tmax = 0.361 | k = −14→11 |
6158 measured reflections | l = −14→13 |
3318 independent reflections |
Refinement on F2 | Primary atom site location: structure-invariant direct methods |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.043 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.079 | H-atom parameters constrained |
S = 0.83 | w = 1/[σ2(Fo2) + (0.0329P)2] where P = (Fo2 + 2Fc2)/3 |
3318 reflections | (Δ/σ)max < 0.001 |
156 parameters | Δρmax = 0.90 e Å−3 |
0 restraints | Δρmin = −0.63 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
Br1 | 0.23622 (8) | 0.50309 (7) | 0.39902 (6) | 0.0407 (2) | |
Co1 | 0.11284 (9) | 0.65284 (7) | 0.33292 (7) | 0.0240 (2) | |
N1 | −0.1140 (5) | 0.6266 (4) | 0.3951 (4) | 0.0275 (12) | |
H1NA | −0.092806 | 0.592787 | 0.450851 | 0.033* | |
H1NB | −0.140672 | 0.701605 | 0.433825 | 0.033* | |
N2 | −0.0369 (5) | 0.5104 (4) | 0.1749 (4) | 0.0267 (12) | |
H2NA | −0.076525 | 0.540610 | 0.118748 | 0.032* | |
H2NB | 0.035086 | 0.457655 | 0.143180 | 0.032* | |
N3 | 0.0362 (6) | 0.7809 (4) | 0.2775 (4) | 0.0318 (13) | |
H3NA | −0.068590 | 0.744083 | 0.215246 | 0.038* | |
H3NB | 0.010553 | 0.842021 | 0.341275 | 0.038* | |
N4 | 0.3228 (6) | 0.6700 (5) | 0.2517 (4) | 0.0288 (12) | |
H4NA | 0.429648 | 0.715828 | 0.310294 | 0.035* | |
H4NB | 0.339174 | 0.592955 | 0.207580 | 0.035* | |
N5 | 0.2648 (6) | 0.7926 (4) | 0.4973 (4) | 0.0310 (12) | |
H5NB | 0.379876 | 0.778385 | 0.510958 | 0.037* | |
H5NA | 0.279042 | 0.865595 | 0.487553 | 0.037* | |
C1 | −0.2779 (7) | 0.5397 (6) | 0.2890 (6) | 0.0389 (18) | |
H1A | −0.335725 | 0.587213 | 0.247390 | 0.047* | |
H1B | −0.372893 | 0.499418 | 0.319885 | 0.047* | |
C2 | −0.2015 (7) | 0.4402 (6) | 0.1987 (5) | 0.0331 (16) | |
H2A | −0.163159 | 0.383288 | 0.235438 | 0.040* | |
H2B | −0.297345 | 0.389624 | 0.120674 | 0.040* | |
C3 | 0.1892 (8) | 0.8384 (6) | 0.2331 (6) | 0.0356 (16) | |
H3A | 0.281827 | 0.907467 | 0.303933 | 0.043* | |
H3B | 0.137264 | 0.872586 | 0.175150 | 0.043* | |
C4 | 0.2801 (8) | 0.7335 (6) | 0.1679 (6) | 0.0325 (15) | |
H4A | 0.194594 | 0.672553 | 0.088508 | 0.039* | |
H4B | 0.395917 | 0.768860 | 0.150396 | 0.039* | |
C5 | 0.1973 (8) | 0.8142 (7) | 0.6138 (5) | 0.0442 (18) | |
H5A | 0.162352 | 0.733048 | 0.620283 | 0.053* | |
H5B | 0.084679 | 0.846984 | 0.608494 | 0.053* | |
C6 | 0.3486 (11) | 0.9092 (7) | 0.7335 (6) | 0.060 (2) | |
H6 | 0.396726 | 0.986063 | 0.720647 | 0.071* | |
C7 | 0.2505 (13) | 0.9469 (9) | 0.8421 (7) | 0.100 (3) | |
H7A | 0.218670 | 0.875620 | 0.863966 | 0.150* | |
H7B | 0.136796 | 0.970529 | 0.816889 | 0.150* | |
H7C | 0.334250 | 1.018126 | 0.913915 | 0.150* | |
C8 | 0.5128 (10) | 0.8535 (8) | 0.7599 (7) | 0.081 (3) | |
H8A | 0.601773 | 0.913826 | 0.836527 | 0.121* | |
H8B | 0.574238 | 0.835317 | 0.691255 | 0.121* | |
H8C | 0.467066 | 0.775759 | 0.768734 | 0.121* | |
Br2 | 0.26843 (8) | 0.36505 (7) | 0.01047 (6) | 0.0434 (2) | |
Br3 | 0.27866 (8) | 0.10929 (6) | 0.53790 (6) | 0.0379 (2) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Br1 | 0.0363 (4) | 0.0475 (5) | 0.0489 (5) | 0.0158 (3) | 0.0119 (3) | 0.0285 (4) |
Co1 | 0.0204 (4) | 0.0230 (5) | 0.0245 (5) | 0.0014 (4) | 0.0038 (3) | 0.0079 (4) |
N1 | 0.031 (3) | 0.030 (3) | 0.021 (3) | 0.007 (2) | 0.005 (2) | 0.011 (3) |
N2 | 0.024 (3) | 0.022 (3) | 0.033 (3) | 0.008 (2) | 0.007 (2) | 0.010 (2) |
N3 | 0.032 (3) | 0.030 (3) | 0.023 (3) | 0.002 (2) | 0.009 (2) | 0.002 (3) |
N4 | 0.021 (2) | 0.030 (3) | 0.029 (3) | 0.005 (2) | 0.003 (2) | 0.007 (3) |
N5 | 0.030 (3) | 0.030 (3) | 0.029 (3) | 0.002 (2) | 0.001 (2) | 0.011 (3) |
C1 | 0.019 (3) | 0.047 (5) | 0.040 (4) | 0.001 (3) | 0.002 (3) | 0.011 (4) |
C2 | 0.023 (3) | 0.025 (4) | 0.039 (4) | −0.005 (3) | 0.002 (3) | 0.007 (3) |
C3 | 0.040 (4) | 0.032 (4) | 0.033 (4) | 0.001 (3) | 0.006 (3) | 0.016 (3) |
C4 | 0.029 (3) | 0.032 (4) | 0.034 (4) | −0.007 (3) | 0.014 (3) | 0.015 (3) |
C5 | 0.051 (4) | 0.051 (5) | 0.022 (4) | 0.008 (4) | 0.006 (3) | 0.009 (4) |
C6 | 0.082 (6) | 0.045 (5) | 0.033 (4) | −0.003 (4) | −0.003 (4) | 0.011 (4) |
C7 | 0.156 (9) | 0.089 (8) | 0.032 (5) | 0.029 (7) | 0.017 (5) | 0.002 (5) |
C8 | 0.066 (5) | 0.095 (7) | 0.063 (6) | −0.030 (5) | −0.019 (4) | 0.046 (6) |
Br2 | 0.0378 (4) | 0.0469 (5) | 0.0378 (4) | 0.0144 (3) | 0.0014 (3) | 0.0107 (4) |
Br3 | 0.0280 (3) | 0.0276 (4) | 0.0471 (4) | 0.0035 (3) | 0.0077 (3) | 0.0055 (4) |
Br1—Co1 | 2.4019 (11) | C1—H1A | 0.9700 |
Co1—N1 | 1.950 (4) | C1—H1B | 0.9700 |
Co1—N3 | 1.962 (5) | C2—H2A | 0.9700 |
Co1—N4 | 1.962 (4) | C2—H2B | 0.9700 |
Co1—N2 | 1.963 (4) | C3—C4 | 1.500 (8) |
Co1—N5 | 1.998 (4) | C3—H3A | 0.9700 |
N1—C1 | 1.486 (6) | C3—H3B | 0.9700 |
N1—H1NA | 0.8900 | C4—H4A | 0.9700 |
N1—H1NB | 0.8900 | C4—H4B | 0.9700 |
N2—C2 | 1.472 (6) | C5—C6 | 1.541 (9) |
N2—H2NA | 0.8900 | C5—H5A | 0.9700 |
N2—H2NB | 0.8900 | C5—H5B | 0.9700 |
N3—C3 | 1.479 (7) | C6—C8 | 1.505 (9) |
N3—H3NA | 0.8900 | C6—C7 | 1.525 (10) |
N3—H3NB | 0.8900 | C6—H6 | 0.9800 |
N4—C4 | 1.464 (7) | C7—H7A | 0.9600 |
N4—H4NA | 0.8900 | C7—H7B | 0.9600 |
N4—H4NB | 0.8900 | C7—H7C | 0.9600 |
N5—C5 | 1.480 (7) | C8—H8A | 0.9600 |
N5—H5NB | 0.8900 | C8—H8B | 0.9600 |
N5—H5NA | 0.8900 | C8—H8C | 0.9600 |
C1—C2 | 1.503 (7) | ||
N1—Co1—N3 | 93.07 (18) | C2—C1—H1A | 110.4 |
N1—Co1—N4 | 173.73 (18) | N1—C1—H1B | 110.4 |
N3—Co1—N4 | 84.75 (19) | C2—C1—H1B | 110.4 |
N1—Co1—N2 | 84.76 (18) | H1A—C1—H1B | 108.6 |
N3—Co1—N2 | 92.30 (19) | N2—C2—C1 | 106.4 (5) |
N4—Co1—N2 | 89.44 (18) | N2—C2—H2A | 110.5 |
N1—Co1—N5 | 94.20 (18) | C1—C2—H2A | 110.5 |
N3—Co1—N5 | 89.98 (19) | N2—C2—H2B | 110.5 |
N4—Co1—N5 | 91.69 (18) | C1—C2—H2B | 110.5 |
N2—Co1—N5 | 177.5 (2) | H2A—C2—H2B | 108.6 |
N1—Co1—Br1 | 92.15 (14) | N3—C3—C4 | 106.7 (5) |
N3—Co1—Br1 | 174.59 (13) | N3—C3—H3A | 110.4 |
N4—Co1—Br1 | 90.21 (14) | C4—C3—H3A | 110.4 |
N2—Co1—Br1 | 89.62 (13) | N3—C3—H3B | 110.4 |
N5—Co1—Br1 | 88.19 (14) | C4—C3—H3B | 110.4 |
C1—N1—Co1 | 110.5 (3) | H3A—C3—H3B | 108.6 |
C1—N1—H1NA | 109.6 | N4—C4—C3 | 107.6 (5) |
Co1—N1—H1NA | 109.6 | N4—C4—H4A | 110.2 |
C1—N1—H1NB | 109.6 | C3—C4—H4A | 110.2 |
Co1—N1—H1NB | 109.6 | N4—C4—H4B | 110.2 |
H1NA—N1—H1NB | 108.1 | C3—C4—H4B | 110.2 |
C2—N2—Co1 | 109.8 (3) | H4A—C4—H4B | 108.5 |
C2—N2—H2NA | 109.7 | N5—C5—C6 | 112.4 (5) |
Co1—N2—H2NA | 109.7 | N5—C5—H5A | 109.1 |
C2—N2—H2NB | 109.7 | C6—C5—H5A | 109.1 |
Co1—N2—H2NB | 109.7 | N5—C5—H5B | 109.1 |
H2NA—N2—H2NB | 108.2 | C6—C5—H5B | 109.1 |
C3—N3—Co1 | 110.5 (3) | H5A—C5—H5B | 107.9 |
C3—N3—H3NA | 109.6 | C8—C6—C7 | 112.3 (7) |
Co1—N3—H3NA | 109.6 | C8—C6—C5 | 111.7 (6) |
C3—N3—H3NB | 109.6 | C7—C6—C5 | 107.5 (6) |
Co1—N3—H3NB | 109.6 | C8—C6—H6 | 108.4 |
H3NA—N3—H3NB | 108.1 | C7—C6—H6 | 108.4 |
C4—N4—Co1 | 109.6 (3) | C5—C6—H6 | 108.4 |
C4—N4—H4NA | 109.7 | C6—C7—H7A | 109.5 |
Co1—N4—H4NA | 109.7 | C6—C7—H7B | 109.5 |
C4—N4—H4NB | 109.7 | H7A—C7—H7B | 109.5 |
Co1—N4—H4NB | 109.7 | C6—C7—H7C | 109.5 |
H4NA—N4—H4NB | 108.2 | H7A—C7—H7C | 109.5 |
C5—N5—Co1 | 120.2 (4) | H7B—C7—H7C | 109.5 |
C5—N5—H5NB | 107.3 | C6—C8—H8A | 109.5 |
Co1—N5—H5NB | 107.3 | C6—C8—H8B | 109.5 |
C5—N5—H5NA | 107.3 | H8A—C8—H8B | 109.5 |
Co1—N5—H5NA | 107.3 | C6—C8—H8C | 109.5 |
H5NB—N5—H5NA | 106.9 | H8A—C8—H8C | 109.5 |
N1—C1—C2 | 106.7 (4) | H8B—C8—H8C | 109.5 |
N1—C1—H1A | 110.4 | ||
Co1—N1—C1—C2 | 37.1 (6) | N3—C3—C4—N4 | −49.4 (6) |
Co1—N2—C2—C1 | 41.1 (5) | Co1—N5—C5—C6 | 170.0 (5) |
N1—C1—C2—N2 | −50.2 (6) | N5—C5—C6—C8 | −69.0 (8) |
Co1—N3—C3—C4 | 36.3 (5) | N5—C5—C6—C7 | 167.4 (6) |
Co1—N4—C4—C3 | 40.1 (5) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1NA···Br1i | 0.89 | 2.68 | 3.458 (5) | 147 |
N1—H1NB···Br3i | 0.89 | 2.50 | 3.348 (5) | 159 |
N2—H2NA···Br2ii | 0.89 | 2.57 | 3.430 (5) | 164 |
N2—H2NB···Br2 | 0.89 | 2.60 | 3.436 (4) | 158 |
N3—H3NA···Br2ii | 0.89 | 2.54 | 3.380 (5) | 158 |
N3—H3NB···Br3i | 0.89 | 2.76 | 3.493 (4) | 141 |
N4—H4NA···Br3iii | 0.89 | 2.56 | 3.430 (4) | 166 |
N4—H4NB···Br2 | 0.89 | 2.69 | 3.521 (5) | 157 |
N5—H5NB···Br3iii | 0.89 | 2.88 | 3.506 (4) | 129 |
N5—H5NA···Br3iv | 0.89 | 2.67 | 3.509 (5) | 159 |
C3—H3A···Br3iv | 0.97 | 2.88 | 3.647 (6) | 137 |
C6—H6···Br3iv | 0.98 | 3.09 | 3.875 (8) | 138 |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x, −y+1, −z; (iii) −x+1, −y+1, −z+1; (iv) x, y+1, z. |
Acknowledgements
The authors thank the Department of Chemistry, Pondicherry University, for the data collection.
Funding information
EG and MM gratefully acknowledge the DST–SERB for a young scientist start-up research grant (YSS/2014/000561) and DST–FIST for providing NMR facilities to the department.
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