cis-Bromidobis(ethyl­ene-1,2-di­amine)(methyl­amine)­cobalt(III) dibromide

Manimaran, S.; Govindan, E.; Manjunathan, M.; Sambathkumar, K.; Anbalagan, K.

doi:10.1107/S2414314618008192

metal-organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 3| Part 6| June 2018| x180819

https://doi.org/10.1107/S2414314618008192

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cis-Bromidobis(ethylene-1,2-diamine)(methylamine)cobalt(III) dibromide

S. Manimaran,^a,^b ^* E. Govindan,^c M. Manjunathan,^b K. Sambathkumar ^d and K. Anbalagan ^e

^aDepartment of Physics, Thanthai Hans Rover College, Perambalur 621 220, India, ^bDepartment of Chemistry, BWDA Arts and Science College, Tindivanam 604 304, India, ^cDepartment of Physics, Thiruvalluvar University College of Arts and Science, Thiruvennainallur 607 203, India, ^dP. G. & Research Department of Physics, A. A. Govt. Arts College, Villupuram, India, and ^eDepartment of Chemistry, Pondicherry University, Pondicherry 605 014, India
^*Correspondence e-mail: drmanirec@gmail.com

Edited by H. Stoeckli-Evans, University of Neuchâtel, Switzerland (Received 18 May 2018; accepted 4 June 2018; online 8 June 2018)

In the title compound, [CoBr(CH₅N)(C₂H₈N₂)₂]Br₂, the cobalt(III) ion has a distorted octahedral coordination environment and is ligated by four N atoms in the equatorial plane, with an additional N atom and a Br⁻ ion occupying the axial positions. In the crystal, the complex cation and the two counter-anions are linked via N—H⋯Br and C—H⋯Br hydrogen bonds, forming a supramolecular framework.

Keywords: crystal structure; cobalt(III) dibromide; methylamine; ethylene-1,2-diamine; hydrogen bonding.

CCDC reference: 894718

Structure description

Mixed-ligand cobalt(III) complexes exhibit 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 B12 and is therefore found physiologically in most tissues. Cobalt(III) complexes are known for their involvement in electron-transfer and ligand-substitution reactions, which find applications in chemical and biological systems. Our present research concerns the design and synthesis of cobalt(III) complexes with the objective of understanding of their structure–reactivity correlations. Substituting an amino ligand for the MeNH₂ moiety can yield complexes of similar structure, but with differing electron-transfer rates (Anbalagan, 2011 ; Anbalagan et al., 2011 ).

The molecular structure of the title compound is illustrated in Fig. 1. The cobalt(III) ion has a distorted octahedral coordination environment and is ligated by four N atoms (N1, N2, N3 and N5) in the equatorial plane, with N atom (N4) and the Br⁻ ion (Br1) occupying the axial positions. The Co1—N(ethylene-1,2-diamine) bond lengths vary from 1.958 (7) to 1.966 (7) Å, comparable with the values reported [1.962 (7) to 1.957 (8) Å] in the literature (Lee et al., 2007 ; Ramesh et al., 2008 ; Anbalagan et al., 2009 ; Ravichandran et al., 2009 ). The Co1—N5 (methylamine) bond length is 1.983 (7) Å, which is also similar to the values of 1.9722 (2) to 1.988 (2) Å reported previously (Manimaran et al., 2018 ). Both five-membered chelate rings adopts twisted conformations (on the C1—C2 and C3—C4 bonds), and their mean planes are inclined to each other by 80.2 (5)°.

Figure 1
Molecular structure of the title compound, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.

In the crystal, molecules are linked by a series of N—H⋯Br hydrogen bonds and a C—H⋯Br hydrogen bond, leading to the formation of a supramolecular framework (Fig. 2 and Table 1)

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—HB⋯Br3ⁱ	0.90	2.67	3.484 (7)	151
N1—HA⋯Br3	0.90	2.52	3.389 (8)	163
N4—H0AB⋯Br2	0.90	2.73	3.485 (7)	142
N4—H0AA⋯Br3	0.90	2.52	3.374 (7)	158
N2—H3AA⋯Br2	0.90	2.66	3.498 (10)	156
N5—H2AB⋯Br2ⁱⁱ	0.90	2.56	3.452 (7)	171
N5—H2AA⋯Br2ⁱⁱⁱ	0.90	2.58	3.447 (7)	161
N3—H1AC⋯Br3	0.90	2.55	3.387 (8)	154
N3—H1AD⋯Br2ⁱⁱ	0.90	2.61	3.511 (7)	174
C5—H11A⋯Br2	0.96	2.85	3.813 (13)	176
Symmetry codes: (i) $[-x, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ ; (ii) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (iii) $[-x+1, y-{\script{1\over 2}}, -z+{\script{3\over 2}}]$ .

Figure 2
A view along the b axis of the crystal packing of the title compound. The N—H⋯Br hydrogen bonds are shown as dashed lines (Table 1

). For clarity, C-bound H atoms have been omitted unless involved in hydrogen bonding.

Synthesis and crystallization

To a suspension of 2 g of trans-[Co(en)₂Br₂]Br, made into a paste using 3–4 drops of water, ca 2 ml of methylamine was added dropwise over 20 min with mixing. The mixture was ground until the colour changed from dull green to red. The reaction mixture was set aside until no further change was observed and then left to stand overnight. Finally, the solid was washed with ethanol, then dissolved in 5–10 ml of water pre-heated to 343 K and allowed to crystallize using hot acidified water (yield 0.75 g). The crystals were filtered off, washed with ethanol and dried under vacuum. Pink block-like crystals were obtained by repeated recrystallization from hot acidified distilled water.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	[CoBr(CH₅N)(C₂H₈N₂)₂]Br₂
M_r	449.90
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	13.2883 (8), 7.5686 (5), 14.3602 (9)
β (°)	103.261 (6)
V (Å³)	1405.75 (15)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	9.73
Crystal size (mm)	0.23 × 0.17 × 0.11

Data collection
Diffractometer	Bruker SMART APEXII area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2008 )
T_min, T_max	0.165, 0.361
No. of measured, independent and observed [I > 2σ(I)] reflections	5583, 2458, 1398
R_int	0.076
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.057, 0.143, 0.89
No. of reflections	2458
No. of parameters	128
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	1.31, −1.14
Computer programs: APEX2 and SAINT (Bruker, 2008), SHELXS97 (Sheldrick 2008 ), SHELXL97 (Sheldrick 2008), PLATON (Spek, 2009 ), SHELXTL (Sheldrick, 2008) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 894718

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2414314618008192/su5443sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314618008192/su5443Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: 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: SHELXTL (Sheldrick, 2008) and publCIF (Westrip, 2010).

cis-Bromidobis(ethylene-1,2-diamine)(methylamine)cobalt(III) dibromide top

Crystal data top

[CoBr(CH₅N)(C₂H₈N₂)₂]Br₂	F(000) = 872
M_r = 449.90	D_x = 2.126 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2458 reflections
a = 13.2883 (8) Å	θ = 2.9–25.0°
b = 7.5686 (5) Å	µ = 9.73 mm⁻¹
c = 14.3602 (9) Å	T = 293 K
β = 103.261 (6)°	Block, pink
V = 1405.75 (15) Å³	0.23 × 0.17 × 0.11 mm
Z = 4

Data collection top

Bruker SMART APEXII area-detector diffractometer	2458 independent reflections
Radiation source: fine-focus sealed tube	1398 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.076
ω and φ scans	θ_max = 25.0°, θ_min = 2.9°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −15→15
T_min = 0.165, T_max = 0.361	k = −9→8
5583 measured reflections	l = −9→17

Refinement top

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)] = 0.057	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.143	H atoms treated by a mixture of independent and constrained refinement
S = 0.89	w = 1/[σ²(F_o²) + (0.0788P)²] where P = (F_o² + 2F_c²)/3
2458 reflections	(Δ/σ)_max = 0.001
128 parameters	Δρ_max = 1.31 e Å⁻³
0 restraints	Δρ_min = −1.14 e Å⁻³

Special details top

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.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > 2sigma(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Br3	−0.00338 (8)	0.22334 (16)	0.61657 (8)	0.0449 (4)
Br2	0.37617 (8)	0.41487 (18)	0.63897 (7)	0.0469 (4)
Br1	0.32768 (9)	−0.27534 (18)	0.87914 (9)	0.0592 (4)
Co1	0.27166 (8)	0.01016 (18)	0.82199 (8)	0.0246 (3)
N1	0.1517 (5)	−0.0985 (11)	0.7355 (5)	0.032 (2)
HB	0.1244	−0.1818	0.7670	0.038*
HA	0.1030	−0.0159	0.7145	0.038*
N4	0.2206 (5)	0.2493 (10)	0.7838 (5)	0.0280 (19)
H0AB	0.2733	0.3175	0.7753	0.034*
H0AA	0.1731	0.2444	0.7280	0.034*
N2	0.3397 (6)	−0.0143 (13)	0.7154 (5)	0.043 (2)
H3AA	0.3696	0.0888	0.7059	0.051*
H3AB	0.3894	−0.0972	0.7295	0.051*
C3	0.1739 (8)	0.3276 (15)	0.8585 (8)	0.047 (3)
HC	0.1244	0.4184	0.8312	0.057*
HD	0.2269	0.3804	0.9086	0.057*
C2	0.2630 (8)	−0.0653 (17)	0.6268 (6)	0.048 (3)
H0AC	0.2306	0.0396	0.5944	0.058*
H0AD	0.2974	−0.1275	0.5838	0.058*
C5	0.4424 (9)	0.2794 (17)	0.9017 (9)	0.060 (4)
H11A	0.4280	0.3193	0.8365	0.090*
H11B	0.5157	0.2798	0.9275	0.090*
H11C	0.4096	0.3569	0.9387	0.090*
C1	0.1843 (8)	−0.1797 (16)	0.6525 (7)	0.043 (3)
H1AB	0.2126	−0.2965	0.6694	0.051*
H1AA	0.1253	−0.1908	0.5987	0.051*
N5	0.4021 (5)	0.0986 (11)	0.9053 (5)	0.028 (2)
H2AB	0.3964	0.0815	0.9659	0.033*
H2AA	0.4524	0.0254	0.8962	0.033*
N3	0.1931 (6)	0.0318 (11)	0.9218 (5)	0.033 (2)
H1AC	0.1588	−0.0694	0.9258	0.039*
H1AD	0.2368	0.0513	0.9787	0.039*
C4	0.1200 (7)	0.1775 (16)	0.8991 (8)	0.043 (3)
H2AD	0.0993	0.2165	0.9563	0.052*
H2AC	0.0588	0.1402	0.8524	0.052*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br3	0.0442 (6)	0.0487 (8)	0.0409 (6)	0.0165 (5)	0.0082 (5)	0.0065 (6)
Br2	0.0452 (7)	0.0633 (10)	0.0341 (6)	−0.0063 (6)	0.0131 (5)	0.0105 (6)
Br1	0.0710 (8)	0.0415 (9)	0.0602 (8)	0.0087 (6)	0.0049 (6)	0.0089 (7)
Co1	0.0289 (7)	0.0234 (8)	0.0218 (6)	0.0044 (6)	0.0064 (5)	0.0027 (6)
N1	0.046 (5)	0.028 (6)	0.024 (4)	0.006 (4)	0.012 (4)	0.000 (4)
N4	0.031 (4)	0.019 (5)	0.037 (5)	0.004 (3)	0.013 (4)	0.004 (4)
N2	0.048 (5)	0.046 (7)	0.039 (5)	0.006 (5)	0.021 (4)	0.002 (5)
C3	0.061 (7)	0.025 (7)	0.060 (8)	0.003 (6)	0.023 (6)	−0.007 (6)
C2	0.064 (7)	0.062 (9)	0.017 (5)	0.008 (6)	0.007 (5)	−0.003 (6)
C5	0.055 (7)	0.052 (10)	0.060 (8)	−0.007 (6)	−0.013 (6)	0.007 (7)
C1	0.056 (7)	0.037 (8)	0.035 (6)	0.004 (6)	0.010 (5)	−0.002 (6)
N5	0.021 (4)	0.035 (6)	0.025 (4)	0.006 (3)	0.001 (3)	0.006 (4)
N3	0.036 (5)	0.035 (6)	0.028 (4)	−0.012 (4)	0.011 (4)	−0.004 (4)
C4	0.034 (6)	0.051 (9)	0.052 (7)	0.003 (5)	0.023 (5)	−0.018 (6)

Geometric parameters (Å, º) top

Br1—Co1	2.3699 (18)	C3—HD	0.9700
Co1—N2	1.958 (7)	C2—C1	1.468 (14)
Co1—N1	1.962 (7)	C2—H0AC	0.9700
Co1—N3	1.963 (7)	C2—H0AD	0.9700
Co1—N4	1.966 (7)	C5—N5	1.475 (14)
Co1—N5	1.983 (7)	C5—H11A	0.9600
N1—C1	1.490 (11)	C5—H11B	0.9600
N1—HB	0.9000	C5—H11C	0.9600
N1—HA	0.9000	C1—H1AB	0.9700
N4—C3	1.482 (12)	C1—H1AA	0.9700
N4—H0AB	0.9000	N5—H2AB	0.9000
N4—H0AA	0.9000	N5—H2AA	0.9000
N2—C2	1.487 (12)	N3—C4	1.456 (13)
N2—H3AA	0.9000	N3—H1AC	0.9000
N2—H3AB	0.9000	N3—H1AD	0.9000
C3—C4	1.528 (15)	C4—H2AD	0.9700
C3—HC	0.9700	C4—H2AC	0.9700

N2—Co1—N1	85.3 (3)	HC—C3—HD	108.6
N2—Co1—N3	175.5 (3)	C1—C2—N2	109.1 (8)
N1—Co1—N3	90.4 (3)	C1—C2—H0AC	109.9
N2—Co1—N4	93.4 (3)	N2—C2—H0AC	109.9
N1—Co1—N4	91.8 (3)	C1—C2—H0AD	109.9
N3—Co1—N4	85.4 (3)	N2—C2—H0AD	109.9
N2—Co1—N5	90.4 (3)	H0AC—C2—H0AD	108.3
N1—Co1—N5	173.7 (3)	N5—C5—H11A	109.5
N3—Co1—N5	93.9 (3)	N5—C5—H11B	109.5
N4—Co1—N5	93.2 (3)	H11A—C5—H11B	109.5
N2—Co1—Br1	91.2 (3)	N5—C5—H11C	109.5
N1—Co1—Br1	89.0 (2)	H11A—C5—H11C	109.5
N3—Co1—Br1	90.0 (3)	H11B—C5—H11C	109.5
N4—Co1—Br1	175.4 (2)	C2—C1—N1	108.2 (9)
N5—Co1—Br1	86.4 (2)	C2—C1—H1AB	110.1
C1—N1—Co1	109.6 (5)	N1—C1—H1AB	110.1
C1—N1—HB	109.7	C2—C1—H1AA	110.1
Co1—N1—HB	109.7	N1—C1—H1AA	110.1
C1—N1—HA	109.7	H1AB—C1—H1AA	108.4
Co1—N1—HA	109.7	C5—N5—Co1	124.5 (6)
HB—N1—HA	108.2	C5—N5—H2AB	106.2
C3—N4—Co1	109.9 (6)	Co1—N5—H2AB	106.2
C3—N4—H0AB	109.7	C5—N5—H2AA	106.2
Co1—N4—H0AB	109.7	Co1—N5—H2AA	106.2
C3—N4—H0AA	109.7	H2AB—N5—H2AA	106.4
Co1—N4—H0AA	109.7	C4—N3—Co1	109.8 (6)
H0AB—N4—H0AA	108.2	C4—N3—H1AC	109.7
C2—N2—Co1	110.1 (6)	Co1—N3—H1AC	109.7
C2—N2—H3AA	109.6	C4—N3—H1AD	109.7
Co1—N2—H3AA	109.6	Co1—N3—H1AD	109.7
C2—N2—H3AB	109.6	H1AC—N3—H1AD	108.2
Co1—N2—H3AB	109.6	N3—C4—C3	107.5 (7)
H3AA—N2—H3AB	108.1	N3—C4—H2AD	110.2
N4—C3—C4	106.8 (9)	C3—C4—H2AD	110.2
N4—C3—HC	110.4	N3—C4—H2AC	110.2
C4—C3—HC	110.4	C3—C4—H2AC	110.2
N4—C3—HD	110.4	H2AD—C4—H2AC	108.5
C4—C3—HD	110.4

N2—Co1—N1—C1	14.7 (7)	Co1—N2—C2—C1	−33.9 (11)
N3—Co1—N1—C1	−166.6 (7)	N2—C2—C1—N1	45.9 (11)
N4—Co1—N1—C1	108.0 (7)	Co1—N1—C1—C2	−37.0 (10)
N5—Co1—N1—C1	−33 (3)	N2—Co1—N5—C5	77.4 (9)
Br1—Co1—N1—C1	−76.6 (6)	N1—Co1—N5—C5	125 (3)
N2—Co1—N4—C3	−172.2 (6)	N3—Co1—N5—C5	−101.7 (9)
N1—Co1—N4—C3	102.4 (6)	N4—Co1—N5—C5	−16.1 (9)
N3—Co1—N4—C3	12.1 (6)	Br1—Co1—N5—C5	168.5 (8)
N5—Co1—N4—C3	−81.6 (6)	N2—Co1—N3—C4	−59 (5)
Br1—Co1—N4—C3	3 (3)	N1—Co1—N3—C4	−75.9 (7)
N1—Co1—N2—C2	10.4 (7)	N4—Co1—N3—C4	15.9 (7)
N3—Co1—N2—C2	−6 (5)	N5—Co1—N3—C4	108.8 (7)
N4—Co1—N2—C2	−81.1 (8)	Br1—Co1—N3—C4	−164.8 (6)
N5—Co1—N2—C2	−174.3 (8)	Co1—N3—C4—C3	−39.5 (9)
Br1—Co1—N2—C2	99.3 (7)	N4—C3—C4—N3	49.1 (10)
Co1—N4—C3—C4	−36.0 (9)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—HB···Br3ⁱ	0.90	2.67	3.484 (7)	151
N1—HA···Br3	0.90	2.52	3.389 (8)	163
N4—H0AB···Br2	0.90	2.73	3.485 (7)	142
N4—H0AA···Br3	0.90	2.52	3.374 (7)	158
N2—H3AA···Br2	0.90	2.66	3.498 (10)	156
N5—H2AB···Br2ⁱⁱ	0.90	2.56	3.452 (7)	171
N5—H2AA···Br2ⁱⁱⁱ	0.90	2.58	3.447 (7)	161
N3—H1AC···Br3	0.90	2.55	3.387 (8)	154
N3—H1AD···Br2ⁱⁱ	0.90	2.61	3.511 (7)	174
C5—H11A···Br2	0.96	2.85	3.813 (13)	176

Symmetry codes: (i) −x, y−1/2, −z+3/2; (ii) x, −y+1/2, z+1/2; (iii) −x+1, y−1/2, −z+3/2.

Acknowledgements

The authors thank the Department of Chemistry, Pondicherry University, for the data collection.

Funding information

SM gratefully acknowledges the DST–SERB for a young scientist start-up research grant (YSS/2014/000561) and the DST–FIST for providing NMR facilities to the department.

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