Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807026852/at2309sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807026852/at2309Isup2.hkl |
CCDC reference: 1148878
Crystals of the title compound were synthesized using hydrothermal method in a Teflon-lined Parr bomb (23 ml), which was then sealed. Manganese(II) chloride tetrahydrate (39.6 mg, 0.2 mmol), potassium thiocyanate (38.9 mg, 0.4 mmol), pyrazine (1.5 ml), and distilled water (2 g) were placed into the bomb and sealed. The bomb was heated under autogenous pressure for 6 d at 413 K and allowed to cool at room temperature for 24 h. Upon opening the bomb, a clear colourless solution was decanted from small yellow crystals. These crystals were washed with distilled water followed by ethanol, and allowed to air-dry at room temperature.
H atoms were positioned geometrically, with C—H = 0.93 Å for aromatic H and constrained to ride on their parent atoms, with Uiso(H) = 1.2Ueq(C).
There are three manganese enzymes containing a mononuclear manganese site, viz. superoxide dismutase, peroxidase and dioxygenase, which participate in redox changes in the respective areas of biology (Law et al., 1999). Carboxylatobridged complexes, such as pyridine, phenanthroline, quinoline and benzimidazole, are often employed to mimic the function and structure of these active sites, based on the knowledge that Mn centres in these enzymes are predominately coordinated by N,O donors from available amino acid side chains (Pecoraro & Butler, 1986; Wu et al., 2003; Pan & Xu, 2004; Liu et al., 2004; Li et al., 2005). We herein report the crystal structure of the title compound, (I).
In the molecule of (I), (Fig. 1) the ligand bond lengths and angles are within normal ranges (Allen et al., 1987). The two N atoms of two SCN- and four N atoms of four pyrazine ligands are coordinated to the Mn atom, in a distorted octahedral arrangement (Table 1). A crystallographic twofold rotation axis passes through the Mn atom, and the N and para-N atoms of two trans pyrazine rings. The planar pyrazine rings I (N3/N6/C4—C7), II (N2/N7/C2A/C3A/C2—C3) and III (N4/N5/C8A/C9A/C8—C9) are nearly perpendicular to each other, with dihedral angles of I/II = 87.7 (2), I/III = 109.2 (6) and II/III = 85.9 (7)°.
In the crystal structure, the non-classical hydrogen bonds and the weak π-π stacking interactions, involving the pyrazine rings of adjacent pyrazine ligands with centroid-centroid distance of 3.3205 (4) Å [symmetry code: 1 - x, 2 - y, 1 - z], cause to the formation of a supramolecular network structure (Fig. 2).
For related literature, see: Allen et al. (1987); Law et al. (1999); Li et al. (2005); Liu et al. (2004); Pan & Xu (2004); Pecoraro & Butler (1986); Wu et al. (2003).
Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Siemens, 1996); software used to prepare material for publication: SHELXTL.
[Mn(NCS)2(C4H4N2)4] | F(000) = 1004 |
Mr = 491.47 | Dx = 1.308 Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 2231 reflections |
a = 11.425 (5) Å | θ = 2.3–23.8° |
b = 14.543 (4) Å | µ = 0.72 mm−1 |
c = 15.022 (3) Å | T = 273 K |
β = 90.759 (5)° | Block, yellow |
V = 2495.7 (15) Å3 | 0.26 × 0.16 × 0.07 mm |
Z = 4 |
Bruker APEXII area-detector diffractometer | 2434 independent reflections |
Radiation source: fine-focus sealed tube | 1675 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.033 |
φ and ω scans | θmax = 26.0°, θmin = 2.3° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −14→13 |
Tmin = 0.836, Tmax = 0.952 | k = −17→17 |
7912 measured reflections | l = −18→18 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.050 | H-atom parameters constrained |
wR(F2) = 0.159 | w = 1/[σ2(Fo2) + (0.1074P)2 + 0.9725P] where P = (Fo2 + 2Fc2)/3 |
S = 1.09 | (Δ/σ)max < 0.001 |
2434 reflections | Δρmax = 0.52 e Å−3 |
144 parameters | Δρmin = −0.39 e Å−3 |
0 restraints | Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.0113 (16) |
[Mn(NCS)2(C4H4N2)4] | V = 2495.7 (15) Å3 |
Mr = 491.47 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 11.425 (5) Å | µ = 0.72 mm−1 |
b = 14.543 (4) Å | T = 273 K |
c = 15.022 (3) Å | 0.26 × 0.16 × 0.07 mm |
β = 90.759 (5)° |
Bruker APEXII area-detector diffractometer | 2434 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 1675 reflections with I > 2σ(I) |
Tmin = 0.836, Tmax = 0.952 | Rint = 0.033 |
7912 measured reflections |
R[F2 > 2σ(F2)] = 0.050 | 0 restraints |
wR(F2) = 0.159 | H-atom parameters constrained |
S = 1.09 | Δρmax = 0.52 e Å−3 |
2434 reflections | Δρmin = −0.39 e Å−3 |
144 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Mn1 | 0.0000 | 0.35963 (4) | 0.7500 | 0.0486 (3) | |
S1 | −0.36253 (15) | 0.36697 (11) | 0.93412 (13) | 0.1233 (6) | |
N1 | −0.1575 (3) | 0.3629 (2) | 0.8242 (3) | 0.0787 (10) | |
N2 | 0.0000 | 0.2153 (3) | 0.7500 | 0.0686 (11) | |
N3 | 0.1076 (3) | 0.3603 (2) | 0.8756 (2) | 0.0694 (8) | |
N4 | 0.0000 | 0.5066 (3) | 0.7500 | 0.0700 (11) | |
N5 | 0.0000 | 0.6957 (5) | 0.7500 | 0.150 (3) | |
N6 | 0.2516 (6) | 0.3887 (4) | 1.0292 (5) | 0.142 (2) | |
N7 | 0.0000 | 0.0280 (5) | 0.7500 | 0.131 (2) | |
C1 | −0.2437 (3) | 0.3646 (2) | 0.8699 (3) | 0.0663 (10) | |
C2 | −0.0418 (4) | 0.1680 (3) | 0.8208 (3) | 0.0785 (11) | |
H2 | −0.0706 | 0.2007 | 0.8691 | 0.094* | |
C3 | −0.0430 (5) | 0.0761 (3) | 0.8235 (3) | 0.0957 (14) | |
H3 | −0.0716 | 0.0449 | 0.8727 | 0.115* | |
C4 | 0.2251 (4) | 0.3423 (3) | 0.8760 (3) | 0.0892 (13) | |
H4 | 0.2572 | 0.3205 | 0.8234 | 0.107* | |
C5 | 0.3009 (5) | 0.3539 (4) | 0.9491 (5) | 0.1116 (19) | |
H5 | 0.3801 | 0.3396 | 0.9456 | 0.134* | |
C6 | 0.1327 (7) | 0.4051 (5) | 1.0275 (4) | 0.140 (3) | |
H6 | 0.0974 | 0.4267 | 1.0788 | 0.168* | |
C7 | 0.0637 (5) | 0.3904 (4) | 0.9517 (3) | 0.1084 (17) | |
H7 | −0.0162 | 0.4022 | 0.9545 | 0.130* | |
C8 | 0.0981 (4) | 0.5541 (3) | 0.7764 (3) | 0.0853 (12) | |
H8 | 0.1652 | 0.5214 | 0.7923 | 0.102* | |
C9 | 0.1006 (5) | 0.6463 (3) | 0.7802 (5) | 0.112 (2) | |
H9 | 0.1663 | 0.6771 | 0.8020 | 0.134* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Mn1 | 0.0436 (5) | 0.0510 (5) | 0.0515 (5) | 0.000 | 0.0112 (3) | 0.000 |
S1 | 0.0995 (11) | 0.1354 (13) | 0.1366 (14) | 0.0019 (8) | 0.0649 (10) | 0.0009 (9) |
N1 | 0.071 (2) | 0.086 (3) | 0.079 (2) | 0.0017 (16) | 0.0187 (17) | −0.0001 (17) |
N2 | 0.074 (3) | 0.065 (3) | 0.067 (3) | 0.000 | 0.005 (2) | 0.000 |
N3 | 0.068 (2) | 0.0669 (19) | 0.074 (2) | 0.0020 (15) | 0.0040 (15) | −0.0021 (15) |
N4 | 0.064 (3) | 0.063 (3) | 0.084 (3) | 0.000 | 0.004 (2) | 0.000 |
N5 | 0.142 (7) | 0.086 (5) | 0.220 (9) | 0.000 | −0.020 (6) | 0.000 |
N6 | 0.148 (5) | 0.141 (4) | 0.134 (5) | 0.002 (4) | −0.031 (4) | −0.020 (4) |
N7 | 0.165 (7) | 0.088 (4) | 0.140 (6) | 0.000 | −0.015 (5) | 0.000 |
C1 | 0.064 (2) | 0.065 (2) | 0.070 (2) | 0.0039 (17) | 0.0125 (17) | −0.0001 (17) |
C2 | 0.087 (3) | 0.070 (2) | 0.078 (3) | −0.006 (2) | 0.005 (2) | 0.009 (2) |
C3 | 0.127 (4) | 0.071 (3) | 0.089 (3) | −0.007 (3) | 0.001 (3) | 0.008 (2) |
C4 | 0.071 (3) | 0.107 (4) | 0.090 (3) | 0.012 (2) | 0.001 (2) | 0.015 (2) |
C5 | 0.076 (3) | 0.130 (5) | 0.127 (5) | −0.001 (3) | −0.019 (3) | 0.026 (4) |
C6 | 0.129 (5) | 0.188 (7) | 0.101 (4) | 0.048 (5) | −0.033 (4) | −0.042 (4) |
C7 | 0.094 (3) | 0.154 (5) | 0.078 (3) | 0.028 (3) | −0.008 (2) | −0.031 (3) |
C8 | 0.074 (3) | 0.071 (3) | 0.111 (3) | −0.009 (2) | −0.003 (2) | 0.005 (2) |
C9 | 0.094 (4) | 0.070 (3) | 0.171 (6) | −0.010 (3) | −0.025 (4) | 0.000 (3) |
Mn1—N1 | 2.130 (4) | N6—C6 | 1.378 (8) |
Mn1—N2 | 2.100 (4) | N6—C5 | 1.428 (9) |
Mn1—N3 | 2.239 (3) | N7—C3i | 1.401 (6) |
Mn1—N4 | 2.137 (4) | N7—C3 | 1.401 (6) |
Mn1—N1i | 2.130 (4) | C2—C3 | 1.338 (6) |
Mn1—N3i | 2.239 (3) | C2—H2 | 0.9300 |
S1—C1 | 1.676 (4) | C3—H3 | 0.9300 |
N1—C1 | 1.209 (6) | C4—C5 | 1.400 (7) |
N2—C2i | 1.359 (5) | C4—H4 | 0.9300 |
N2—C2 | 1.359 (5) | C5—H5 | 0.9300 |
N3—C7 | 1.328 (6) | C6—C7 | 1.393 (7) |
N3—C4 | 1.368 (5) | C6—H6 | 0.9300 |
N4—C8 | 1.371 (5) | C7—H7 | 0.9300 |
N4—C8i | 1.371 (5) | C8—C9 | 1.342 (6) |
N5—C9 | 1.424 (6) | C8—H8 | 0.9300 |
N5—C9i | 1.424 (6) | C9—H9 | 0.9300 |
N1—Mn1—N2 | 91.29 (9) | C3i—N7—C3 | 120.2 (6) |
N1—Mn1—N3 | 90.98 (14) | N1—C1—S1 | 179.5 (4) |
N1—Mn1—N4 | 88.71 (9) | C3—C2—N2 | 122.2 (4) |
N2—Mn1—N3 | 90.26 (8) | C3—C2—H2 | 118.9 |
N2—Mn1—N4 | 180.000 (1) | N2—C2—H2 | 118.9 |
N3—Mn1—N4 | 89.74 (8) | C2—C3—N7 | 118.1 (5) |
N2—Mn1—N1i | 91.29 (9) | C2—C3—H3 | 121.0 |
N1i—Mn1—N1 | 177.42 (19) | N7—C3—H3 | 121.0 |
N1i—Mn1—N4 | 88.71 (9) | N3—C4—C5 | 125.2 (5) |
N1i—Mn1—N3 | 89.01 (14) | N3—C4—H4 | 117.4 |
N2—Mn1—N3i | 90.26 (8) | C5—C4—H4 | 117.4 |
N1i—Mn1—N3i | 90.98 (14) | C4—C5—N6 | 117.2 (5) |
N1—Mn1—N3i | 89.01 (14) | C4—C5—H5 | 121.4 |
N4—Mn1—N3i | 89.74 (8) | N6—C5—H5 | 121.4 |
N3—Mn1—N3i | 179.48 (15) | N6—C6—C7 | 122.4 (6) |
C1—N1—Mn1 | 176.9 (4) | N6—C6—H6 | 118.8 |
C2i—N2—C2 | 119.2 (5) | C7—C6—H6 | 118.8 |
C2i—N2—Mn1 | 120.4 (3) | N3—C7—C6 | 122.5 (5) |
C2—N2—Mn1 | 120.4 (3) | N3—C7—H7 | 118.8 |
C7—N3—C4 | 116.3 (4) | C6—C7—H7 | 118.8 |
C7—N3—Mn1 | 121.1 (3) | C9—C8—N4 | 122.2 (5) |
C4—N3—Mn1 | 122.0 (3) | C9—C8—H8 | 118.9 |
C8—N4—C8i | 119.4 (5) | N4—C8—H8 | 118.9 |
C8—N4—Mn1 | 120.3 (2) | C8—C9—N5 | 118.3 (5) |
C8i—N4—Mn1 | 120.3 (2) | C8—C9—H9 | 120.9 |
C9—N5—C9i | 119.4 (6) | N5—C9—H9 | 120.9 |
C6—N6—C5 | 116.5 (5) |
Symmetry code: (i) −x, y, −z+3/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4···N1i | 0.93 | 2.55 | 3.109 (6) | 119 |
C7—H7···N1 | 0.93 | 2.58 | 3.176 (6) | 122 |
Symmetry code: (i) −x, y, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | [Mn(NCS)2(C4H4N2)4] |
Mr | 491.47 |
Crystal system, space group | Monoclinic, C2/c |
Temperature (K) | 273 |
a, b, c (Å) | 11.425 (5), 14.543 (4), 15.022 (3) |
β (°) | 90.759 (5) |
V (Å3) | 2495.7 (15) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.72 |
Crystal size (mm) | 0.26 × 0.16 × 0.07 |
Data collection | |
Diffractometer | Bruker APEXII area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.836, 0.952 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7912, 2434, 1675 |
Rint | 0.033 |
(sin θ/λ)max (Å−1) | 0.618 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.050, 0.159, 1.09 |
No. of reflections | 2434 |
No. of parameters | 144 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.52, −0.39 |
Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1996), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Siemens, 1996), SHELXTL.
Mn1—N1 | 2.130 (4) | Mn1—N3 | 2.239 (3) |
Mn1—N2 | 2.100 (4) | Mn1—N4 | 2.137 (4) |
N1—Mn1—N2 | 91.29 (9) | N2—Mn1—N3 | 90.26 (8) |
N1—Mn1—N3 | 90.98 (14) | N2—Mn1—N4 | 180.000 (1) |
N1—Mn1—N4 | 88.71 (9) | N3—Mn1—N4 | 89.74 (8) |
D—H···A | D—H | H···A | D···A | D—H···A |
C4—H4···N1i | 0.93 | 2.55 | 3.109 (6) | 119 |
C7—H7···N1 | 0.93 | 2.58 | 3.176 (6) | 122 |
Symmetry code: (i) −x, y, −z+3/2. |
There are three manganese enzymes containing a mononuclear manganese site, viz. superoxide dismutase, peroxidase and dioxygenase, which participate in redox changes in the respective areas of biology (Law et al., 1999). Carboxylatobridged complexes, such as pyridine, phenanthroline, quinoline and benzimidazole, are often employed to mimic the function and structure of these active sites, based on the knowledge that Mn centres in these enzymes are predominately coordinated by N,O donors from available amino acid side chains (Pecoraro & Butler, 1986; Wu et al., 2003; Pan & Xu, 2004; Liu et al., 2004; Li et al., 2005). We herein report the crystal structure of the title compound, (I).
In the molecule of (I), (Fig. 1) the ligand bond lengths and angles are within normal ranges (Allen et al., 1987). The two N atoms of two SCN- and four N atoms of four pyrazine ligands are coordinated to the Mn atom, in a distorted octahedral arrangement (Table 1). A crystallographic twofold rotation axis passes through the Mn atom, and the N and para-N atoms of two trans pyrazine rings. The planar pyrazine rings I (N3/N6/C4—C7), II (N2/N7/C2A/C3A/C2—C3) and III (N4/N5/C8A/C9A/C8—C9) are nearly perpendicular to each other, with dihedral angles of I/II = 87.7 (2), I/III = 109.2 (6) and II/III = 85.9 (7)°.
In the crystal structure, the non-classical hydrogen bonds and the weak π-π stacking interactions, involving the pyrazine rings of adjacent pyrazine ligands with centroid-centroid distance of 3.3205 (4) Å [symmetry code: 1 - x, 2 - y, 1 - z], cause to the formation of a supramolecular network structure (Fig. 2).