catena-Poly[[diaqua­dibromidoman­ganese(III)]-μ-pyridine-2-carboxyl­ato]

Kim, N.-H.; Ha, K.

doi:10.1107/S160053680902844X

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Pages m983-m984

doi:10.1107/S160053680902844X

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catena-Poly[[diaquadibromidomanganese(III)]-μ-pyridine-2-carboxylato]

Nam-Ho Kim ^a and Kwang Ha ^a ^*

^aSchool of Applied Chemical Engineering, the Research Institute of Catalysis, Chonnam National University, Gwangju 500-757, Republic of Korea
^*Correspondence e-mail: hakwang@chonnam.ac.kr

(Received 8 July 2009; accepted 18 July 2009; online 25 July 2009)

The asymmetric unit of the title compound, [MnBr₂(C₆H₄NO₂)(H₂O)₂]_n, contains one monomeric unit of the neutral linear coordination polymer. The Mn³⁺ ions are bridged by anionic pyridine-2-carboxylate (pic) ligands, thereby forming a chain-like structure along the c axis, and are six-coordinated in a distorted octahedral environment by two O atoms of the two different carboxylate groups, two O atoms of two water molecules and two Br atoms. The complex displays intermolecular O—H⋯Br, O—H⋯N, O—H⋯O, C—H⋯O and C—H⋯Br hydrogen bonding. There may also be intermolecular π–π interactions between adjacent pyridine rings, with a centroid–centroid distance of 3.993 (8) Å.

Related literature

For the synthesis and structure of [Mn(pic)₃], see: Figgis et al. (1978 ); Yamaguchi & Sawyer (1985 ); Li et al. (2000 ). For the synthesis and structure of [Mn(pic)₂(H₂O)₂], see: Okabe & Koizumi (1998 ); Barandika et al. (1999 ). For details of mono-, di- and polynuclear Mn(II, III, IV)–pic complexes, see: Huang et al. (2004 ). For the synthesis and structure of the anionic Mn(II)–pic polymer, {[MnBr₂(pic)(H₂O)]⁻}_n, see: Kim et al. (2009 ).

Experimental

Crystal data

[MnBr₂(C₆H₄NO₂)(H₂O)₂]
M_r = 372.89
Monoclinic, P 2₁ /c
a = 10.290 (3) Å
b = 13.814 (4) Å
c = 7.978 (3) Å
β = 109.810 (6)°
V = 1066.9 (6) Å³
Z = 4
Mo Kα radiation
μ = 8.71 mm⁻¹
T = 223 K
0.25 × 0.23 × 0.10 mm

Data collection

Bruker SMART 1000 CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.133, T_max = 0.418
6572 measured reflections
2168 independent reflections
1510 reflections with I > 2σ(I)
R_int = 0.060

Refinement

R[F² > 2σ(F²)] = 0.070
wR(F²) = 0.248
S = 1.14
2168 reflections
127 parameters
H-atom parameters constrained
Δρ_max = 2.85 e Å⁻³
Δρ_min = −1.46 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O3—H3A⋯Br1ⁱ	0.83	2.58	3.340 (9)	154
O3—H3B⋯N1ⁱⁱ	1.10	2.41	3.466 (14)	162
O4—H4A⋯Br2ⁱⁱⁱ	0.83	2.70	3.333 (9)	135
O4—H4A⋯O1ⁱⁱⁱ	0.83	2.33	2.908 (14)	127
O4—H4B⋯Br1^iv	1.02	2.31	3.210 (9)	147
C2—H2⋯O4^v	0.94	2.59	3.319 (18)	134
C4—H4⋯Br2^vi	0.94	2.80	3.534 (12)	135
Symmetry codes: (i) -x+2, -y, -z+1; (ii) $[-x+2, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (iii) $[x, -y+{\script{1\over 2}}, z+{\script{1\over 2}}]$ ; (iv) $[x, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (v) $[x-1, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (vi) -x+2, -y, -z.

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ) and PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S160053680902844X/im2127sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S160053680902844X/im2127Isup2.hkl

checkCIF report

Comment top

Coordination polymers are attracting great attention because of their potential applications such as in catalysis, magnetism, molecular recognition and other fields (Huang et al., 2004).

The asymmetric unit of the title compound, [MnBr₂(C₆H₄NO₂)(H₂O)₂]_n, contains one monomeric unit of the neutral linear coordination polymer (Fig. 1). Mn³⁺ ions are bridged by anionic pyridinecarboxylate (pic) ligands, thereby forming a one-dimensional zigzag chain-like structure along the c axis (Fig. 2). Mn³⁺ ions are six-coordinated in a distorted octahedral environment by two O atoms of the two different carboxylate groups, two O atoms of two water molecules and two Br atoms. Water molecules are trans with respect to each other, whereas Br atoms and O atoms of the carboxylate groups are cis with respect to each other, respectively. The complex displays intermolecular O—H···Br, O—H···N, O—H···O, C—H···O and C—H···Br hydrogen bonding (Table 1 and Fig. 2). There may also be intermolecular π-π interactions between adjacent pyridine rings, with a centroid-centroid distance of 3.993 (8) Å. The structure of the complex polymer is comparable with the structure of the anionic complex polymer, {[MnBr₂(pic)(H₂O)]^-}_n, in which the Mn²⁺ ions are linked to each other by pyridinecarboxylate bridges in a syn-anti mode (Kim et al., 2009).

Related literature top

For the synthesis and structure of [Mn(pic)₃], see: Figgis et al. (1978); Yamaguchi & Sawyer (1985); Li et al. (2000). For the synthesis and structure of [Mn(pic)₂(H₂O)₂], see: Okabe & Koizumi (1998); Barandika et al. (1999). For details of mono-, di- and polynuclear Mn(II, III, IV)–pic complexes, see: Huang et al. (2004). For the synthesis and structure of the anionic Mn(II)–pic polymer, {[MnBr₂(pic)(H₂O)]^-}_n, see: Kim et al. (2009).

Experimental top

A solution of MnBr₂ × 4 H₂O (0.920 g, 3.208 mmol) and pyridine-2-carboxylic acid (0.200 g, 1.625 mmol) in H₂O (10 ml) was refluxed for 3 h. The solvent was removed in vacuum, the residue was dissolved in MeOH/H₂O (5 ml/5 ml) and filtered. After evaporation of the solvent, the residue was dried at 333 K, to give a pale pink powder (0.918 g). Crystals suitable for X-ray analysis were obtained by slow evaporation from a CH₃CN solution.

Computing details top

Data collection: SMART (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top

	Fig. 1. The repeat unit of the title compound, with displacement ellipsoids drawn at the 50% probability level for non-H atoms.
	Fig. 2. View of the unit-cell contents and chain-like structure of the title compound. Hydrogen-bond interactions are drawn with dashed lines.

catena-Poly[[diaquadibromidomanganese(III)]-µ-pyridine-2-carboxylato] top

Crystal data top

[MnBr₂(C₆H₄NO₂)(H₂O)₂]	F(000) = 712
M_r = 372.89	D_x = 2.321 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 2889 reflections
a = 10.290 (3) Å	θ = 2.6–28.2°
b = 13.814 (4) Å	µ = 8.71 mm⁻¹
c = 7.978 (3) Å	T = 223 K
β = 109.810 (6)°	Plate, colorless
V = 1066.9 (6) Å³	0.25 × 0.23 × 0.10 mm
Z = 4

Data collection top

Bruker SMART 1000 CCD diffractometer	2168 independent reflections
Radiation source: fine-focus sealed tube	1510 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.060
ϕ and ω scans	θ_max = 26.4°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −12→11
T_min = 0.133, T_max = 0.418	k = −17→17
6572 measured reflections	l = −5→9

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)] = 0.070	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.248	H-atom parameters constrained
S = 1.14	w = 1/[σ²(F_o²) + (0.135P)² + 7.437P] where P = (F_o² + 2F_c²)/3
2168 reflections	(Δ/σ)_max < 0.001
127 parameters	Δρ_max = 2.85 e Å⁻³
0 restraints	Δρ_min = −1.46 e Å⁻³

Crystal data top

[MnBr₂(C₆H₄NO₂)(H₂O)₂]	V = 1066.9 (6) Å³
M_r = 372.89	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 10.290 (3) Å	µ = 8.71 mm⁻¹
b = 13.814 (4) Å	T = 223 K
c = 7.978 (3) Å	0.25 × 0.23 × 0.10 mm
β = 109.810 (6)°

Data collection top

Bruker SMART 1000 CCD diffractometer	2168 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	1510 reflections with I > 2σ(I)
T_min = 0.133, T_max = 0.418	R_int = 0.060
6572 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.070	0 restraints
wR(F²) = 0.248	H-atom parameters constrained
S = 1.14	Δρ_max = 2.85 e Å⁻³
2168 reflections	Δρ_min = −1.46 e Å⁻³
127 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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
Mn1	1.11555 (19)	0.12215 (13)	0.3085 (2)	0.0262 (5)
Br1	1.27174 (14)	0.06169 (8)	0.63672 (16)	0.0287 (4)
Br2	1.29649 (14)	0.06032 (9)	0.17035 (17)	0.0322 (4)
O1	0.9974 (9)	0.1781 (7)	0.0294 (12)	0.037 (2)
O2	0.9538 (9)	0.1716 (6)	0.4164 (12)	0.033 (2)
O3	1.0017 (9)	−0.0140 (6)	0.2414 (12)	0.039 (2)
H3A	0.9255	−0.0079	0.2534	0.059*
H3B	1.0868	−0.0659	0.2907	0.059*
O4	1.1968 (11)	0.2673 (6)	0.3608 (12)	0.039 (2)
H4A	1.1943	0.2857	0.4586	0.058*
H4B	1.1898	0.3074	0.2510	0.058*
N1	0.7263 (11)	0.3399 (7)	0.0142 (14)	0.031 (2)
C1	0.6010 (14)	0.3448 (9)	0.0408 (19)	0.035 (3)
H1	0.5611	0.4054	0.0464	0.042*
C2	0.5345 (14)	0.2620 (11)	0.059 (2)	0.041 (4)
H2	0.4469	0.2652	0.0714	0.049*
C3	0.5976 (14)	0.1726 (12)	0.0593 (18)	0.042 (4)
H3	0.5538	0.1153	0.0750	0.050*
C4	0.7258 (12)	0.1683 (9)	0.0361 (16)	0.027 (3)
H4	0.7690	0.1083	0.0367	0.032*
C5	0.7886 (12)	0.2528 (8)	0.0123 (14)	0.025 (3)
C6	0.9277 (13)	0.2547 (9)	−0.0176 (15)	0.027 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Mn1	0.0264 (10)	0.0225 (9)	0.0289 (10)	−0.0013 (7)	0.0085 (8)	0.0024 (7)
Br1	0.0340 (8)	0.0267 (7)	0.0244 (7)	0.0015 (5)	0.0085 (5)	0.0002 (4)
Br2	0.0366 (8)	0.0356 (8)	0.0276 (7)	0.0081 (5)	0.0149 (6)	0.0039 (5)
O1	0.027 (5)	0.048 (5)	0.036 (5)	0.013 (4)	0.012 (4)	0.016 (4)
O2	0.029 (5)	0.039 (5)	0.038 (5)	0.003 (4)	0.024 (4)	−0.005 (4)
O3	0.042 (6)	0.026 (5)	0.049 (6)	−0.015 (4)	0.015 (5)	0.003 (4)
O4	0.058 (7)	0.033 (5)	0.030 (5)	−0.007 (4)	0.020 (5)	0.000 (4)
N1	0.032 (6)	0.031 (6)	0.028 (6)	0.006 (5)	0.007 (5)	0.003 (4)
C1	0.028 (7)	0.035 (7)	0.053 (8)	0.010 (5)	0.030 (6)	−0.007 (6)
C2	0.015 (6)	0.061 (10)	0.049 (9)	0.005 (6)	0.014 (6)	0.002 (7)
C3	0.024 (7)	0.063 (9)	0.037 (8)	−0.020 (7)	0.008 (6)	−0.002 (7)
C4	0.025 (6)	0.022 (6)	0.033 (7)	−0.004 (5)	0.009 (5)	0.001 (5)
C5	0.020 (6)	0.044 (7)	0.004 (5)	−0.003 (5)	−0.003 (4)	0.001 (4)
C6	0.025 (6)	0.040 (7)	0.008 (5)	−0.003 (5)	−0.005 (4)	0.007 (5)

Geometric parameters (Å, º) top

Mn1—O4	2.158 (9)	N1—C5	1.365 (15)
Mn1—O3	2.184 (8)	N1—C1	1.378 (16)
Mn1—O2	2.224 (8)	C1—C2	1.366 (19)
Mn1—O1	2.281 (9)	C1—H1	0.94
Mn1—Br2	2.608 (2)	C2—C3	1.40 (2)
Mn1—Br1	2.699 (2)	C2—H2	0.94
O1—C6	1.261 (14)	C3—C4	1.394 (18)
O2—C6ⁱ	1.217 (14)	C3—H3	0.94
O3—H3A	0.83	C4—C5	1.378 (16)
O3—H3B	1.10	C4—H4	0.94
O4—H4A	0.83	C5—C6	1.529 (18)
O4—H4B	1.02	C6—O2ⁱⁱ	1.217 (14)

O4—Mn1—O3	171.1 (4)	Mn1—O4—H4B	115
O4—Mn1—O2	86.1 (4)	H4A—O4—H4B	129
O3—Mn1—O2	87.1 (3)	C5—N1—C1	120.9 (11)
O4—Mn1—O1	85.2 (4)	C2—C1—N1	120.3 (12)
O3—Mn1—O1	89.3 (3)	C2—C1—H1	119.9
O2—Mn1—O1	93.0 (3)	N1—C1—H1	119.9
O4—Mn1—Br2	95.8 (3)	C1—C2—C3	119.5 (12)
O3—Mn1—Br2	90.8 (3)	C1—C2—H2	120.3
O2—Mn1—Br2	177.4 (3)	C3—C2—H2	120.3
O1—Mn1—Br2	85.3 (2)	C4—C3—C2	119.9 (13)
O4—Mn1—Br1	92.1 (3)	C4—C3—H3	120.1
O3—Mn1—Br1	93.7 (2)	C2—C3—H3	120.1
O2—Mn1—Br1	89.9 (2)	C5—C4—C3	119.5 (12)
O1—Mn1—Br1	175.9 (2)	C5—C4—H4	120.3
Br2—Mn1—Br1	91.89 (7)	C3—C4—H4	120.3
C6—O1—Mn1	129.5 (8)	N1—C5—C4	120.0 (12)
C6ⁱ—O2—Mn1	136.7 (9)	N1—C5—C6	117.1 (10)
Mn1—O3—H3A	110	C4—C5—C6	122.9 (11)
Mn1—O3—H3B	100	O2ⁱⁱ—C6—O1	130.0 (13)
H3A—O3—H3B	134	O2ⁱⁱ—C6—C5	115.9 (11)
Mn1—O4—H4A	109	O1—C6—C5	114.1 (10)

O4—Mn1—O1—C6	−47.0 (11)	C2—C3—C4—C5	−0.3 (19)
O3—Mn1—O1—C6	125.9 (11)	C1—N1—C5—C4	0.4 (17)
O2—Mn1—O1—C6	38.8 (11)	C1—N1—C5—C6	−179.8 (10)
Br2—Mn1—O1—C6	−143.2 (11)	C3—C4—C5—N1	1.0 (18)
O4—Mn1—O2—C6ⁱ	−3.1 (12)	C3—C4—C5—C6	−178.8 (10)
O3—Mn1—O2—C6ⁱ	−177.3 (12)	Mn1—O1—C6—O2ⁱⁱ	107.2 (14)
O1—Mn1—O2—C6ⁱ	−88.1 (12)	Mn1—O1—C6—C5	−73.5 (12)
Br1—Mn1—O2—C6ⁱ	89.0 (12)	N1—C5—C6—O2ⁱⁱ	−19.0 (15)
C5—N1—C1—C2	−2 (2)	C4—C5—C6—O2ⁱⁱ	160.8 (12)
N1—C1—C2—C3	3 (2)	N1—C5—C6—O1	161.6 (10)
C1—C2—C3—C4	−2 (2)	C4—C5—C6—O1	−18.6 (15)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···Br1ⁱⁱⁱ	0.83	2.58	3.340 (9)	154
O3—H3B···N1^iv	1.10	2.41	3.466 (14)	162
O4—H4A···Br2ⁱ	0.83	2.70	3.333 (9)	135
O4—H4A···O1ⁱ	0.83	2.33	2.908 (14)	127
O4—H4B···Br1ⁱⁱ	1.02	2.31	3.210 (9)	147
C2—H2···O4^v	0.94	2.59	3.319 (18)	134
C4—H4···Br2^vi	0.94	2.80	3.534 (12)	135

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

Experimental details

Crystal data
Chemical formula	[MnBr₂(C₆H₄NO₂)(H₂O)₂]
M_r	372.89
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	223
a, b, c (Å)	10.290 (3), 13.814 (4), 7.978 (3)
β (°)	109.810 (6)
V (Å³)	1066.9 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	8.71
Crystal size (mm)	0.25 × 0.23 × 0.10

Data collection
Diffractometer	Bruker SMART 1000 CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.133, 0.418
No. of measured, independent and observed [I > 2σ(I)] reflections	6572, 2168, 1510
R_int	0.060
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.070, 0.248, 1.14
No. of reflections	2168
No. of parameters	127
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	2.85, −1.46

Computer programs: SMART (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3A···Br1ⁱ	0.83	2.58	3.340 (9)	154
O3—H3B···N1ⁱⁱ	1.10	2.41	3.466 (14)	162
O4—H4A···Br2ⁱⁱⁱ	0.83	2.70	3.333 (9)	135
O4—H4A···O1ⁱⁱⁱ	0.83	2.33	2.908 (14)	127
O4—H4B···Br1^iv	1.02	2.31	3.210 (9)	147
C2—H2···O4^v	0.94	2.59	3.319 (18)	134
C4—H4···Br2^vi	0.94	2.80	3.534 (12)	135

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

Acknowledgements

This work was supported by a Korea Research Foundation grant funded by the Korean Government (MOEHRD) (KRF-2007–412-J02001).

References

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