4-(Dimethyl­amino)pyridinium tri­bromido­{3-[bromo/hydro­(0.9/0.1)]-4-(dimethyl­amino)pyridine-κN1}cobaltate(II)

Lo, K.M.; Ng, S.W.

doi:10.1107/S1600536809027913

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Pages m958-m959

doi:10.1107/S1600536809027913

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4-(Dimethylamino)pyridinium tribromido{3-[bromo/hydro(0.9/0.1)]-4-(dimethylamino)pyridine-κN¹}cobaltate(II)

Kong Mun Lo ^a and Seik Weng Ng ^a ^*

^aDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
^*Correspondence e-mail: seikweng@um.edu.my

(Received 4 July 2009; accepted 15 July 2009; online 22 July 2009)

The reaction of a cobalt(II) salt with 4-(dimethylamino)pyridinium hydrobromide perbromide yielded the title compound, (C₇H₁₁N₂)[CoBr₃(C₇H_9.1Br_0.9N₂)]. In the anion, the Co^II atom is coordinated in a distorted tetrahedral geometry by three Br atoms and the pyridine N atom of a bromine-substituted 4-(dimethylamino)pyridine molecule, whose formation probably results from an incomplete substitution (90%) catalysed by the Co^II ion. One of the three bromine atoms bonded to the metal is disordered over two sites in a 0.9:0.1 ratio. An N—H⋯Br hydrogen bond connects the cation and anion.

Related literature

For bis(4-(dimethylamino)pyridinium) tetrabromidocobaltate, see: Lo & Ng (2009 ). For other trihalocobaltate(II) anions having a pyridine-type donor ligand, see: Bogdanović et al. (2001 ); Crane et al. (2004 ); Divjaković et al. (1982 ); Hahn et al. (1997 ); Mueller-Westerhoff et al. (1996 ); Sumner & Steinmetz (1985 ).

Experimental

Crystal data

(C₇H₁₁N₂)[CoBr₃(C₇H_9.1Br_0.9N₂)]
M_r = 615.02
Triclinic, $[P \overline 1]$
a = 8.3768 (2) Å
b = 10.2622 (2) Å
c = 12.4691 (3) Å
α = 99.028 (2)°
β = 98.927 (1)°
γ = 106.933 (2)°
V = 989.57 (4) Å³
Z = 2
Mo Kα radiation
μ = 8.74 mm⁻¹
T = 150 K
0.40 × 0.20 × 0.10 mm

Data collection

Bruker APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ) T_min = 0.128, T_max = 0.475 (expected range = 0.112–0.417)
7974 measured reflections
4451 independent reflections
3019 reflections with I > 2σ(I)
R_int = 0.053

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.130
S = 0.97
4451 reflections
221 parameters
7 restraints
H-atom parameters constrained
Δρ_max = 1.29 e Å⁻³
Δρ_min = −1.04 e Å⁻³

Table 1
Selected bond lengths (Å)

Co1—Br1	2.4086 (11)
Co1—Br2	2.3958 (10)
Co1—Br3	2.3814 (13)
Co1—Br3′	2.376 (9)
Co1—N1	2.032 (5)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3⋯Br1	0.88	2.74	3.434 (6)	137

Data collection: APEX2 (Bruker, 2007 ); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001 ); software used to prepare material for publication: publCIF (Westrip, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809027913/hy2210sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809027913/hy2210Isup2.hkl

checkCIF report

Comment top

The reaction of cobalt(II) nitrate and 4-(dimethylamino)pyridinium hydrobromide perbromide yields bis(4-(dimethylamino)pyridinium) tetrabromidocobaltate (Lo & Ng, 2009). A similar reaction with cobalt acetate in place of cobalt nitrate yields a new 4-(dimethylamino)pyridinium salt, [C₇H₁₁N₂][CoBr₃(C₇H_9.1Br_0.9N₂)] (Scheme 1, Fig. 1). The Co^II atom is coordinated by a bromine-substituted 4-(dimethylamino)pyridine molecule, whose formation probably results from an incomplete (90%) electrophilic substitution of 4-(dimethylamino)pyridine that is probabably catalyzed by the cobaltous ion.

Related literature top

For bis(4-(dimethylamino)pyridinium) tetrabromidocobaltate, see: Lo & Ng (2009). For other trihalocobaltate(II) anions having a pyridine-type donor ligand, see: Bogdanović et al. (2001); Crane et al. (2004); Divjaković et al. (1982); Hahn et al. (1997); Mueller-Westerhoff et al. (1996); Sumner & Steinmetz (1985).

Experimental top

Green cobalt acetate (0.70 g, 2.8 mmol) dissolved in water (2 ml) and 4-(dimethylamino)pyridinium hydrobromide perbromide (1.00 g, 2.8 mmol) dissolved in ethanol (50 ml) were mixed and the mixture was heated for one hour. The red solution was filtered; well-formed deep-blue crystals were isolated from the solution after several days.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2009).

Figures top

Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 70% probability level. Minor disordered sites are omitted for clarity.

4-(Dimethylamino)pyridinium tribromido{3-[bromo/hydro(0.9/0.1)]-4- (dimethylamino)pyridine-κN¹}cobaltate(II) top

Crystal data top

(C₇H₁₁N₂)[CoBr₃(C₇H_9.1Br_0.9N₂)]	Z = 2
M_r = 615.02	F(000) = 591.2
Triclinic, P1	D_x = 2.064 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.3768 (2) Å	Cell parameters from 6987 reflections
b = 10.2622 (2) Å	θ = 2.4–28.3°
c = 12.4691 (3) Å	µ = 8.74 mm⁻¹
α = 99.028 (2)°	T = 150 K
β = 98.927 (1)°	Block, brown
γ = 106.933 (2)°	0.40 × 0.20 × 0.10 mm
V = 989.57 (4) Å³

Data collection top

Bruker APEXII CCD diffractometer	4451 independent reflections
Radiation source: fine-focus sealed tube	3019 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.053
ϕ and ω scans	θ_max = 27.5°, θ_min = 1.7°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −10→10
T_min = 0.128, T_max = 0.475	k = −12→13
7974 measured reflections	l = −16→16

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.130	H-atom parameters constrained
S = 0.97	w = 1/[σ²(F_o²) + (0.0634P)²] where P = (F_o² + 2F_c²)/3
4451 reflections	(Δ/σ)_max = 0.001
221 parameters	Δρ_max = 1.29 e Å⁻³
7 restraints	Δρ_min = −1.04 e Å⁻³

Crystal data top

(C₇H₁₁N₂)[CoBr₃(C₇H_9.1Br_0.9N₂)]	γ = 106.933 (2)°
M_r = 615.02	V = 989.57 (4) Å³
Triclinic, P1	Z = 2
a = 8.3768 (2) Å	Mo Kα radiation
b = 10.2622 (2) Å	µ = 8.74 mm⁻¹
c = 12.4691 (3) Å	T = 150 K
α = 99.028 (2)°	0.40 × 0.20 × 0.10 mm
β = 98.927 (1)°

Data collection top

Bruker APEXII CCD diffractometer	4451 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	3019 reflections with I > 2σ(I)
T_min = 0.128, T_max = 0.475	R_int = 0.053
7974 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	7 restraints
wR(F²) = 0.130	H-atom parameters constrained
S = 0.97	Δρ_max = 1.29 e Å⁻³
4451 reflections	Δρ_min = −1.04 e Å⁻³
221 parameters

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

	x	y	z	U_iso*/U_eq	Occ. (<1)
Br1	0.26488 (9)	0.68358 (8)	0.54136 (5)	0.0375 (2)
Br2	0.64945 (8)	0.59464 (7)	0.69989 (5)	0.03080 (18)
Br3	0.49021 (18)	0.89737 (12)	0.84679 (11)	0.0315 (3)	0.90
Br3'	0.531 (2)	0.8775 (13)	0.8695 (11)	0.068 (5)	0.10
Br4	0.30233 (9)	0.25573 (8)	0.96716 (6)	0.0350 (2)	0.90
Co1	0.41492 (10)	0.67837 (9)	0.72097 (7)	0.0271 (2)
N1	0.2478 (6)	0.5344 (5)	0.7796 (4)	0.0280 (12)
N2	−0.0965 (6)	0.2792 (5)	0.9321 (4)	0.0276 (12)
N3	0.6361 (7)	0.7246 (6)	0.4462 (5)	0.0414 (15)
H3	0.5580	0.6723	0.4751	0.050*
N4	1.0006 (7)	0.9742 (6)	0.3157 (4)	0.0318 (12)
C1	0.2977 (8)	0.4510 (6)	0.8403 (5)	0.0267 (13)
H1	0.4135	0.4540	0.8492	0.032*
C2	0.1936 (7)	0.3618 (6)	0.8904 (5)	0.0226 (12)
H2'	0.2368	0.3026	0.9293	0.027*	0.10
C3	0.0191 (7)	0.3572 (6)	0.8846 (5)	0.0248 (13)
C4	−0.0282 (8)	0.4425 (7)	0.8152 (5)	0.0320 (15)
H4	−0.1438	0.4404	0.8015	0.038*
C5	0.0825 (8)	0.5267 (7)	0.7677 (6)	0.0338 (15)
H5	0.0420	0.5830	0.7239	0.041*
C6	−0.0620 (10)	0.1971 (10)	1.0125 (8)	0.063 (3)
H6A	0.0449	0.2503	1.0660	0.094*
H6B	−0.0516	0.1101	0.9737	0.094*
H6C	−0.1559	0.1756	1.0518	0.094*
C7	−0.2699 (8)	0.2868 (7)	0.9146 (6)	0.0377 (16)
H7A	−0.3213	0.2596	0.8349	0.057*
H7B	−0.2661	0.3824	0.9433	0.057*
H7C	−0.3385	0.2234	0.9537	0.057*
C8	0.7904 (10)	0.7112 (7)	0.4577 (5)	0.0362 (16)
H8	0.8148	0.6441	0.4962	0.043*
C9	0.9138 (9)	0.7919 (7)	0.4155 (5)	0.0320 (15)
H9	1.0236	0.7811	0.4254	0.038*
C10	0.8813 (7)	0.8921 (6)	0.3568 (4)	0.0240 (13)
C11	0.7136 (9)	0.9012 (7)	0.3454 (5)	0.0360 (16)
H11	0.6826	0.9655	0.3062	0.043*
C12	0.5987 (9)	0.8172 (8)	0.3908 (6)	0.0405 (17)
H12	0.4871	0.8243	0.3831	0.049*
C13	0.9613 (11)	1.0765 (8)	0.2567 (6)	0.051 (2)
H13A	0.9162	1.1366	0.3038	0.076*
H13B	0.8758	1.0282	0.1881	0.076*
H13C	1.0654	1.1334	0.2384	0.076*
C14	1.1733 (9)	0.9648 (8)	0.3293 (6)	0.048 (2)
H14A	1.2214	0.9768	0.4084	0.073*
H14B	1.2452	1.0380	0.2994	0.073*
H14C	1.1689	0.8733	0.2893	0.073*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0327 (4)	0.0541 (5)	0.0345 (4)	0.0205 (3)	0.0109 (3)	0.0188 (3)
Br2	0.0220 (3)	0.0369 (4)	0.0365 (4)	0.0102 (3)	0.0092 (3)	0.0119 (3)
Br3	0.0321 (5)	0.0292 (5)	0.0328 (5)	0.0089 (4)	0.0070 (3)	0.0071 (4)
Br3'	0.076 (9)	0.060 (7)	0.057 (7)	0.001 (5)	0.034 (6)	0.001 (5)
Br4	0.0253 (4)	0.0469 (5)	0.0403 (4)	0.0144 (3)	0.0087 (3)	0.0237 (4)
Co1	0.0236 (5)	0.0288 (5)	0.0310 (5)	0.0068 (4)	0.0110 (3)	0.0108 (4)
N1	0.025 (3)	0.030 (3)	0.031 (3)	0.008 (2)	0.009 (2)	0.011 (2)
N2	0.022 (3)	0.031 (3)	0.029 (3)	0.003 (2)	0.010 (2)	0.013 (2)
N3	0.033 (3)	0.047 (4)	0.034 (3)	−0.005 (3)	0.011 (3)	0.007 (3)
N4	0.026 (3)	0.038 (3)	0.026 (3)	0.002 (2)	0.003 (2)	0.010 (2)
C1	0.017 (3)	0.033 (4)	0.028 (3)	0.007 (3)	0.007 (2)	0.002 (3)
C2	0.023 (3)	0.023 (3)	0.025 (3)	0.009 (2)	0.008 (2)	0.010 (2)
C3	0.020 (3)	0.025 (3)	0.024 (3)	0.000 (2)	0.006 (2)	0.000 (2)
C4	0.023 (3)	0.035 (4)	0.039 (4)	0.007 (3)	0.004 (3)	0.015 (3)
C5	0.024 (3)	0.039 (4)	0.046 (4)	0.014 (3)	0.011 (3)	0.020 (3)
C6	0.036 (5)	0.085 (7)	0.083 (6)	0.017 (5)	0.021 (4)	0.058 (5)
C7	0.024 (4)	0.042 (4)	0.049 (4)	0.008 (3)	0.017 (3)	0.010 (3)
C8	0.055 (5)	0.029 (4)	0.023 (3)	0.011 (3)	0.007 (3)	0.007 (3)
C9	0.036 (4)	0.031 (4)	0.027 (3)	0.012 (3)	0.001 (3)	0.002 (3)
C10	0.027 (3)	0.025 (3)	0.015 (3)	0.003 (3)	0.002 (2)	0.003 (2)
C11	0.033 (4)	0.045 (4)	0.030 (4)	0.014 (3)	0.002 (3)	0.013 (3)
C12	0.023 (4)	0.059 (5)	0.033 (4)	0.007 (3)	0.002 (3)	0.008 (3)
C13	0.060 (5)	0.035 (4)	0.050 (5)	−0.001 (4)	0.008 (4)	0.022 (4)
C14	0.031 (4)	0.056 (5)	0.045 (5)	−0.003 (4)	0.013 (3)	−0.002 (4)

Geometric parameters (Å, º) top

Co1—Br1	2.4086 (11)	C4—H4	0.9500
Co1—Br2	2.3958 (10)	C5—H5	0.9500
Co1—Br3	2.3814 (13)	C6—H6A	0.9800
Co1—Br3'	2.376 (9)	C6—H6B	0.9800
Br4—C2	1.888 (6)	C6—H6C	0.9800
Co1—N1	2.032 (5)	C7—H7A	0.9800
N1—C1	1.340 (8)	C7—H7B	0.9800
N1—C5	1.347 (8)	C7—H7C	0.9800
N2—C3	1.343 (7)	C8—C9	1.356 (9)
N2—C6	1.454 (9)	C8—H8	0.9500
N2—C7	1.461 (8)	C9—C10	1.416 (8)
N3—C8	1.328 (9)	C9—H9	0.9500
N3—C12	1.338 (9)	C10—C11	1.421 (9)
N3—H3	0.8800	C11—C12	1.353 (9)
N4—C10	1.333 (7)	C11—H11	0.9500
N4—C13	1.456 (9)	C12—H12	0.9500
N4—C14	1.463 (9)	C13—H13A	0.9800
C1—C2	1.368 (8)	C13—H13B	0.9800
C1—H1	0.9500	C13—H13C	0.9800
C2—C3	1.439 (8)	C14—H14A	0.9800
C2—H2'	0.9500	C14—H14B	0.9800
C3—C4	1.415 (9)	C14—H14C	0.9800
C4—C5	1.350 (9)

N1—Co1—Br3'	105.5 (5)	N2—C6—H6A	109.5
N1—Co1—Br3	107.98 (15)	N2—C6—H6B	109.5
Br3'—Co1—Br3	12.5 (4)	H6A—C6—H6B	109.5
N1—Co1—Br2	106.97 (14)	N2—C6—H6C	109.5
Br3'—Co1—Br2	104.7 (4)	H6A—C6—H6C	109.5
Br3—Co1—Br2	114.67 (5)	H6B—C6—H6C	109.5
N1—Co1—Br1	105.94 (15)	N2—C7—H7A	109.5
Br3'—Co1—Br1	123.1 (4)	N2—C7—H7B	109.5
Br3—Co1—Br1	111.17 (5)	H7A—C7—H7B	109.5
Br2—Co1—Br1	109.64 (4)	N2—C7—H7C	109.5
C1—N1—C5	116.2 (5)	H7A—C7—H7C	109.5
C1—N1—Co1	122.3 (4)	H7B—C7—H7C	109.5
C5—N1—Co1	121.2 (4)	N3—C8—C9	121.1 (6)
C3—N2—C6	125.9 (5)	N3—C8—H8	119.5
C3—N2—C7	119.4 (5)	C9—C8—H8	119.5
C6—N2—C7	114.3 (5)	C8—C9—C10	120.9 (6)
C8—N3—C12	120.3 (6)	C8—C9—H9	119.5
C8—N3—H3	119.9	C10—C9—H9	119.5
C12—N3—H3	119.9	N4—C10—C9	122.3 (6)
C10—N4—C13	120.2 (6)	N4—C10—C11	121.8 (6)
C10—N4—C14	121.2 (6)	C9—C10—C11	115.9 (6)
C13—N4—C14	118.6 (6)	C12—C11—C10	119.2 (6)
N1—C1—C2	124.6 (5)	C12—C11—H11	120.4
N1—C1—H1	117.7	C10—C11—H11	120.4
C2—C1—H1	117.7	N3—C12—C11	122.6 (6)
C1—C2—C3	120.5 (5)	N3—C12—H12	118.7
C1—C2—Br4	114.0 (4)	C11—C12—H12	118.7
C3—C2—Br4	125.5 (4)	N4—C13—H13A	109.5
C1—C2—H2'	119.8	N4—C13—H13B	109.5
C3—C2—H2'	119.8	H13A—C13—H13B	109.5
N2—C3—C4	120.3 (5)	N4—C13—H13C	109.5
N2—C3—C2	127.4 (6)	H13A—C13—H13C	109.5
C4—C3—C2	112.2 (5)	H13B—C13—H13C	109.5
C5—C4—C3	123.4 (6)	N4—C14—H14A	109.5
C5—C4—H4	118.3	N4—C14—H14B	109.5
C3—C4—H4	118.3	H14A—C14—H14B	109.5
N1—C5—C4	122.9 (6)	N4—C14—H14C	109.5
N1—C5—H5	118.6	H14A—C14—H14C	109.5
C4—C5—H5	118.6	H14B—C14—H14C	109.5

Br3'—Co1—N1—C1	−83.8 (6)	Br4—C2—C3—C4	−176.4 (5)
Br3—Co1—N1—C1	−96.6 (5)	N2—C3—C4—C5	177.9 (6)
Br2—Co1—N1—C1	27.3 (5)	C2—C3—C4—C5	−5.0 (9)
Br1—Co1—N1—C1	144.2 (4)	C1—N1—C5—C4	1.3 (9)
Br3'—Co1—N1—C5	90.1 (7)	Co1—N1—C5—C4	−173.0 (5)
Br3—Co1—N1—C5	77.3 (5)	C3—C4—C5—N1	1.8 (11)
Br2—Co1—N1—C5	−158.8 (5)	C12—N3—C8—C9	1.0 (10)
Br1—Co1—N1—C5	−41.9 (5)	N3—C8—C9—C10	−0.6 (10)
C5—N1—C1—C2	−0.6 (9)	C13—N4—C10—C9	−179.5 (6)
Co1—N1—C1—C2	173.6 (5)	C14—N4—C10—C9	0.0 (9)
N1—C1—C2—C3	−3.0 (9)	C13—N4—C10—C11	−0.2 (9)
N1—C1—C2—Br4	178.6 (5)	C14—N4—C10—C11	179.3 (6)
C6—N2—C3—C4	−174.2 (7)	C8—C9—C10—N4	179.1 (6)
C7—N2—C3—C4	−2.0 (9)	C8—C9—C10—C11	−0.3 (9)
C6—N2—C3—C2	9.1 (10)	N4—C10—C11—C12	−178.6 (6)
C7—N2—C3—C2	−178.7 (6)	C9—C10—C11—C12	0.7 (9)
C1—C2—C3—N2	−177.7 (6)	C8—N3—C12—C11	−0.5 (10)
Br4—C2—C3—N2	0.5 (9)	C10—C11—C12—N3	−0.3 (11)
C1—C2—C3—C4	5.4 (8)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···Br1	0.88	2.74	3.434 (6)	137

Experimental details

Crystal data
Chemical formula	(C₇H₁₁N₂)[CoBr₃(C₇H_9.1Br_0.9N₂)]
M_r	615.02
Crystal system, space group	Triclinic, P1
Temperature (K)	150
a, b, c (Å)	8.3768 (2), 10.2622 (2), 12.4691 (3)
α, β, γ (°)	99.028 (2), 98.927 (1), 106.933 (2)
V (Å³)	989.57 (4)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	8.74
Crystal size (mm)	0.40 × 0.20 × 0.10

Data collection
Diffractometer	Bruker APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996)
T_min, T_max	0.128, 0.475
No. of measured, independent and observed [I > 2σ(I)] reflections	7974, 4451, 3019
R_int	0.053
(sin θ/λ)_max (Å⁻¹)	0.650

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.130, 0.97
No. of reflections	4451
No. of parameters	221
No. of restraints	7
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.29, −1.04

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), X-SEED (Barbour, 2001), publCIF (Westrip, 2009).

Selected bond lengths (Å) top

Co1—Br1	2.4086 (11)	Co1—Br3'	2.376 (9)
Co1—Br2	2.3958 (10)	Co1—N1	2.032 (5)
Co1—Br3	2.3814 (13)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N3—H3···Br1	0.88	2.74	3.434 (6)	137

Acknowledgements

We thank the University of Malaya (RG020/09AFR) for supporting this study.

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