metal-organic compounds
Diaquabis(2-ethyl-5-methylimidazole-4-sulfonato-κ2N3,O)nickel(II) dihydrate
aChemistry Division, Code 6100 Naval Research Laboratory, 4555 Overlook Avenue SW, Washington, DC 20375, USA, and bDepartment of Chemistry, Howard University, 525 College Street NW, Washington, DC 20059, USA
*Correspondence e-mail: andrew.purdy@nrl.navy.mil
In the title complex, [Ni(C6H9N2O3S)2(H2O)2]·2H2O, the NiII atom lies on an inversion center and is chelated by N and O atoms of two symmetry-equivalent imidazolesulfonate ligands in the basal plane, and two water O atoms in axial positions in an overall octahedral configuration. The displays O—H⋯O and N—H⋯O hydrogen bonds, which connect the components into an extended three-dimensional network.
CCDC reference: 973660
Related literature
For examples of Ni–sulfonate complexes and MOFs, see: Lobana et al. (2004); Forbes & Sevov (2009); Kim et al. (2004); Yang et al. (2010). A small number of structurally characterized imidazole sulfonates are known, see: Kuhn et al. (2001, 2002); Chidambaram et al. (1988). The 2-ethyl-4-methyl-5-sulfonate ligand is described by Purdy et al. (2007) and Purdy & Butcher (2011).
Experimental
Crystal data
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Data collection: CrysAlis PRO (Agilent, 2012); cell CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL.
Supporting information
CCDC reference: 973660
https://doi.org/10.1107/S1600536813032169/jj2177sup1.cif
contains datablocks I, New_Global_Publ_Block. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536813032169/jj2177Isup2.hkl
A solution of the potassium salt of the 2-ethyl-4-methyl-imidazole-5-sulfonic acid was prepared by combining 1 g (5.25 mmol) of the free acid with 1.5 equivalents of KOH solution, and diluting the solution to 1M based on K+. (All solutions were made with distilled water.) Two test reactions were done in vials with 0.5 M solutions of Ni(BF4)2·6H2O and MnSO4·H2O, a 0.2 ml metered pipet was used for the additions, and each vial contained one addition of all three solutions. After 1 month, one vial were heated to a boil and allowed to cool and the other remained at room temperature. After one year, large blue crystals of the title compound grew in the solution that was not heated.
The Ni atom lies on an inversion center and is chelated by N1 and O1 of the 2 symmetry equivalent imidazolesulfonate ligands in a plane, and 2 axial water molecules coordinated in an overall octahedral configuration. All of the Ni—O bond lengths (2.083 (2), 2.094 (2) Å) are about the same, and are in the normal range for octahedral coordinated Ni (2.05–2.12 Å). The largest deviation from the 90 ° angles of the octahedron is N1—Ni—O1, a result of the sulfonate group being attached to the imidazole ring. Two additional uncoordinated water molecules are present, but do not lie on any symmetry elements. There are no links other than hydrogen bonds between molecules, in contrast to the analogous unsolvated Cu(II) derivative (Purdy & Butcher, 2011). Hydrogen bonding links all the water molecules and N2, O2, and O3 into an extended structure in all three dimensions.
For examples of Ni–sulfonate complexes and MOFs, see: Lobana et al. (2004); Forbes & Sevov (2009); Kim et al. (2004); Yang et al. (2010). A small number of structurally characterized imidazole sulfonates are known, see: Kuhn et al. (2001, 2002); Chidambaram et al. (1988). The 2-ethyl-4-methyl-5-sulfonate ligand is described by Purdy et al. (2007) and Purdy & Butcher (2011).
Data collection: CrysAlis PRO (Agilent, 2012); cell
CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).Fig. 1. Diagram of C12H22N4O8S2Ni, with uncoordinated water molecules not shown. | |
Fig. 2. Packing diagram viewed down the c axis, displaying the hydrogen bonded interactions of both the coordinated and uncoordinated water molecules. |
[Ni(C6H9N2O3S)2(H2O)2]·2H2O | F(000) = 532 |
Mr = 509.20 | Dx = 1.632 Mg m−3 |
Monoclinic, P21/a | Cu Kα radiation, λ = 1.54178 Å |
Hall symbol: -P 2yab | Cell parameters from 4614 reflections |
a = 7.6037 (2) Å | θ = 5.2–75.5° |
b = 16.8934 (4) Å | µ = 3.77 mm−1 |
c = 8.6574 (3) Å | T = 123 K |
β = 111.303 (3)° | Block, blue |
V = 1036.08 (5) Å3 | 0.52 × 0.46 × 0.35 mm |
Z = 2 |
Agilent Xcalibur Ruby Gemini diffractometer | 2126 independent reflections |
Radiation source: Enhance (Cu) X-ray Source | 2062 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.000 |
Detector resolution: 10.5081 pixels mm-1 | θmax = 75.8°, θmin = 5.2° |
ω scans | h = −9→8 |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012) | k = 0→21 |
Tmin = 0.209, Tmax = 1.000 | l = 0→10 |
2126 measured 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)] = 0.045 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.112 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.18 | w = 1/[σ2(Fo2) + (0.0411P)2 + 2.2827P] where P = (Fo2 + 2Fc2)/3 |
2126 reflections | (Δ/σ)max < 0.001 |
151 parameters | Δρmax = 0.73 e Å−3 |
48 restraints | Δρmin = −0.54 e Å−3 |
[Ni(C6H9N2O3S)2(H2O)2]·2H2O | V = 1036.08 (5) Å3 |
Mr = 509.20 | Z = 2 |
Monoclinic, P21/a | Cu Kα radiation |
a = 7.6037 (2) Å | µ = 3.77 mm−1 |
b = 16.8934 (4) Å | T = 123 K |
c = 8.6574 (3) Å | 0.52 × 0.46 × 0.35 mm |
β = 111.303 (3)° |
Agilent Xcalibur Ruby Gemini diffractometer | 2126 independent reflections |
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2012) | 2062 reflections with I > 2σ(I) |
Tmin = 0.209, Tmax = 1.000 | Rint = 0.000 |
2126 measured reflections |
R[F2 > 2σ(F2)] = 0.045 | 48 restraints |
wR(F2) = 0.112 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.18 | Δρmax = 0.73 e Å−3 |
2126 reflections | Δρmin = −0.54 e Å−3 |
151 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 | ||
Ni | 0.5000 | 0.5000 | 0.5000 | 0.00455 (19) | |
S1 | 0.13784 (8) | 0.60394 (4) | 0.38692 (7) | 0.00676 (18) | |
O1 | 0.2439 (3) | 0.54424 (11) | 0.3337 (2) | 0.0082 (4) | |
O2 | 0.1485 (3) | 0.68145 (12) | 0.3149 (2) | 0.0148 (4) | |
O3 | −0.0536 (3) | 0.58051 (13) | 0.3598 (2) | 0.0165 (4) | |
O1W | 0.3581 (3) | 0.40250 (11) | 0.5452 (2) | 0.0104 (4) | |
H1W1 | 0.422 (5) | 0.378 (2) | 0.629 (4) | 0.027 (11)* | |
H1W2 | 0.267 (4) | 0.417 (2) | 0.563 (5) | 0.027 (11)* | |
O2W | 0.5754 (3) | 0.30842 (12) | 0.8196 (2) | 0.0129 (4) | |
H2W1 | 0.667 (4) | 0.309 (2) | 0.795 (5) | 0.014 (9)* | |
H2W2 | 0.519 (5) | 0.2680 (16) | 0.790 (5) | 0.019 (10)* | |
N1 | 0.4281 (3) | 0.56704 (13) | 0.6667 (3) | 0.0065 (4) | |
N2 | 0.3814 (3) | 0.63709 (13) | 0.8610 (3) | 0.0094 (5) | |
H2A | 0.3996 | 0.6567 | 0.9598 | 0.011* | |
C1 | 0.2651 (4) | 0.61089 (15) | 0.5997 (3) | 0.0072 (5) | |
C2 | 0.2329 (4) | 0.65519 (15) | 0.7178 (3) | 0.0085 (5) | |
C3 | 0.0834 (4) | 0.71410 (17) | 0.7081 (4) | 0.0155 (6) | |
H3A | −0.0366 | 0.6972 | 0.6241 | 0.023* | |
H3B | 0.1188 | 0.7659 | 0.6777 | 0.023* | |
H3C | 0.0696 | 0.7179 | 0.8161 | 0.023* | |
C4 | 0.4953 (4) | 0.58422 (15) | 0.8257 (3) | 0.0083 (5) | |
C5 | 0.6769 (4) | 0.55417 (16) | 0.9505 (3) | 0.0110 (5) | |
H5A | 0.6884 | 0.4968 | 0.9328 | 0.013* | |
H5B | 0.6752 | 0.5615 | 1.0634 | 0.013* | |
C6 | 0.8474 (4) | 0.59737 (17) | 0.9371 (4) | 0.0152 (6) | |
H6A | 0.9637 | 0.5738 | 1.0147 | 0.023* | |
H6B | 0.8420 | 0.6534 | 0.9641 | 0.023* | |
H6C | 0.8457 | 0.5925 | 0.8237 | 0.023* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ni | 0.0030 (3) | 0.0058 (3) | 0.0026 (3) | 0.0012 (2) | −0.0017 (2) | −0.0004 (2) |
S1 | 0.0039 (3) | 0.0098 (3) | 0.0042 (3) | 0.0027 (2) | −0.0014 (2) | 0.0007 (2) |
O1 | 0.0067 (7) | 0.0098 (7) | 0.0051 (7) | 0.0030 (6) | −0.0012 (5) | −0.0014 (6) |
O2 | 0.0208 (11) | 0.0099 (9) | 0.0122 (9) | 0.0059 (8) | 0.0043 (8) | 0.0056 (7) |
O3 | 0.0112 (8) | 0.0241 (8) | 0.0131 (7) | −0.0003 (6) | 0.0031 (6) | −0.0012 (6) |
O1W | 0.0087 (9) | 0.0105 (9) | 0.0108 (9) | 0.0002 (7) | 0.0023 (7) | 0.0014 (7) |
O2W | 0.0164 (10) | 0.0113 (9) | 0.0105 (9) | −0.0051 (8) | 0.0042 (8) | −0.0044 (7) |
N1 | 0.0054 (8) | 0.0070 (8) | 0.0056 (7) | 0.0000 (6) | 0.0002 (6) | 0.0002 (6) |
N2 | 0.0121 (11) | 0.0102 (11) | 0.0050 (10) | −0.0014 (8) | 0.0020 (8) | −0.0025 (8) |
C1 | 0.0065 (8) | 0.0075 (8) | 0.0065 (8) | −0.0002 (7) | 0.0008 (7) | −0.0005 (7) |
C2 | 0.0078 (12) | 0.0081 (11) | 0.0085 (12) | −0.0012 (9) | 0.0015 (10) | −0.0021 (9) |
C3 | 0.0132 (14) | 0.0129 (13) | 0.0197 (14) | 0.0028 (11) | 0.0052 (11) | −0.0049 (11) |
C4 | 0.0110 (13) | 0.0059 (11) | 0.0077 (12) | −0.0021 (9) | 0.0029 (10) | −0.0003 (9) |
C5 | 0.0115 (9) | 0.0116 (9) | 0.0081 (8) | 0.0007 (7) | 0.0013 (7) | 0.0007 (7) |
C6 | 0.0104 (13) | 0.0177 (14) | 0.0122 (13) | −0.0012 (10) | −0.0023 (10) | −0.0014 (10) |
Ni—N1 | 2.058 (2) | N2—C4 | 1.354 (4) |
Ni—N1i | 2.058 (2) | N2—C2 | 1.374 (3) |
Ni—O1W | 2.0825 (19) | N2—H2A | 0.8800 |
Ni—O1Wi | 2.0825 (19) | C1—C2 | 1.359 (4) |
Ni—O1 | 2.0941 (18) | C2—C3 | 1.490 (4) |
Ni—O1i | 2.0941 (18) | C3—H3A | 0.9800 |
S1—O3 | 1.443 (2) | C3—H3B | 0.9800 |
S1—O2 | 1.465 (2) | C3—H3C | 0.9800 |
S1—O1 | 1.4662 (18) | C4—C5 | 1.499 (4) |
S1—C1 | 1.746 (3) | C5—C6 | 1.528 (4) |
O1W—H1W1 | 0.823 (19) | C5—H5A | 0.9900 |
O1W—H1W2 | 0.808 (19) | C5—H5B | 0.9900 |
O2W—H2W1 | 0.798 (18) | C6—H6A | 0.9800 |
O2W—H2W2 | 0.796 (18) | C6—H6B | 0.9800 |
N1—C4 | 1.315 (3) | C6—H6C | 0.9800 |
N1—C1 | 1.378 (3) | ||
N1—Ni—N1i | 180.0 | C4—N2—H2A | 125.5 |
N1—Ni—O1W | 90.90 (8) | C2—N2—H2A | 125.5 |
N1i—Ni—O1W | 89.10 (8) | C2—C1—N1 | 111.1 (2) |
N1—Ni—O1Wi | 89.10 (8) | C2—C1—S1 | 130.4 (2) |
N1i—Ni—O1Wi | 90.90 (8) | N1—C1—S1 | 118.48 (19) |
O1W—Ni—O1Wi | 180.00 (6) | C1—C2—N2 | 104.1 (2) |
N1—Ni—O1 | 82.42 (8) | C1—C2—C3 | 131.9 (2) |
N1i—Ni—O1 | 97.58 (8) | N2—C2—C3 | 124.0 (2) |
O1W—Ni—O1 | 89.75 (8) | C2—C3—H3A | 109.5 |
O1Wi—Ni—O1 | 90.25 (8) | C2—C3—H3B | 109.5 |
N1—Ni—O1i | 97.58 (8) | H3A—C3—H3B | 109.5 |
N1i—Ni—O1i | 82.42 (8) | C2—C3—H3C | 109.5 |
O1W—Ni—O1i | 90.25 (8) | H3A—C3—H3C | 109.5 |
O1Wi—Ni—O1i | 89.75 (8) | H3B—C3—H3C | 109.5 |
O1—Ni—O1i | 180.00 (14) | N1—C4—N2 | 110.2 (2) |
O3—S1—O2 | 112.61 (13) | N1—C4—C5 | 125.8 (2) |
O3—S1—O1 | 113.45 (12) | N2—C4—C5 | 123.9 (2) |
O2—S1—O1 | 111.06 (11) | C4—C5—C6 | 111.6 (2) |
O3—S1—C1 | 109.24 (12) | C4—C5—H5A | 109.3 |
O2—S1—C1 | 107.09 (12) | C6—C5—H5A | 109.3 |
O1—S1—C1 | 102.73 (11) | C4—C5—H5B | 109.3 |
S1—O1—Ni | 120.66 (10) | C6—C5—H5B | 109.3 |
Ni—O1W—H1W1 | 112 (3) | H5A—C5—H5B | 108.0 |
Ni—O1W—H1W2 | 109 (3) | C5—C6—H6A | 109.5 |
H1W1—O1W—H1W2 | 105 (3) | C5—C6—H6B | 109.5 |
H2W1—O2W—H2W2 | 110 (3) | H6A—C6—H6B | 109.5 |
C4—N1—C1 | 105.7 (2) | C5—C6—H6C | 109.5 |
C4—N1—Ni | 138.96 (19) | H6A—C6—H6C | 109.5 |
C1—N1—Ni | 115.34 (16) | H6B—C6—H6C | 109.5 |
C4—N2—C2 | 109.0 (2) | ||
O3—S1—O1—Ni | −124.06 (13) | Ni—N1—C1—S1 | 1.0 (3) |
O2—S1—O1—Ni | 107.92 (14) | O3—S1—C1—C2 | −57.4 (3) |
C1—S1—O1—Ni | −6.27 (15) | O2—S1—C1—C2 | 64.8 (3) |
N1—Ni—O1—S1 | 6.10 (13) | O1—S1—C1—C2 | −178.1 (3) |
N1i—Ni—O1—S1 | −173.90 (13) | O3—S1—C1—N1 | 124.0 (2) |
O1W—Ni—O1—S1 | 97.04 (13) | O2—S1—C1—N1 | −113.8 (2) |
O1Wi—Ni—O1—S1 | −82.96 (13) | O1—S1—C1—N1 | 3.2 (2) |
O1i—Ni—O1—S1 | 89 (6) | N1—C1—C2—N2 | −0.2 (3) |
N1i—Ni—N1—C4 | 81 (8) | S1—C1—C2—N2 | −178.9 (2) |
O1W—Ni—N1—C4 | 89.7 (3) | N1—C1—C2—C3 | 177.0 (3) |
O1Wi—Ni—N1—C4 | −90.3 (3) | S1—C1—C2—C3 | −1.7 (5) |
O1—Ni—N1—C4 | 179.4 (3) | C4—N2—C2—C1 | 0.2 (3) |
O1i—Ni—N1—C4 | −0.6 (3) | C4—N2—C2—C3 | −177.3 (3) |
N1i—Ni—N1—C1 | −102 (8) | C1—N1—C4—N2 | −0.1 (3) |
O1W—Ni—N1—C1 | −93.13 (18) | Ni—N1—C4—N2 | 177.21 (19) |
O1Wi—Ni—N1—C1 | 86.87 (18) | C1—N1—C4—C5 | −176.8 (2) |
O1—Ni—N1—C1 | −3.50 (17) | Ni—N1—C4—C5 | 0.5 (4) |
O1i—Ni—N1—C1 | 176.50 (17) | C2—N2—C4—N1 | 0.0 (3) |
C4—N1—C1—C2 | 0.2 (3) | C2—N2—C4—C5 | 176.7 (2) |
Ni—N1—C1—C2 | −177.83 (17) | N1—C4—C5—C6 | 76.8 (3) |
C4—N1—C1—S1 | 179.10 (18) | N2—C4—C5—C6 | −99.4 (3) |
Symmetry code: (i) −x+1, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—H1W1···O2W | 0.82 (2) | 2.02 (2) | 2.837 (3) | 174 (4) |
O1W—H1W2···O3ii | 0.81 (2) | 1.96 (2) | 2.739 (3) | 161 (4) |
O2W—H2W1···O2i | 0.80 (2) | 1.97 (2) | 2.751 (3) | 167 (4) |
O2W—H2W1···S1i | 0.80 (2) | 2.92 (3) | 3.602 (2) | 145 (3) |
O2W—H2W2···O2iii | 0.80 (2) | 1.94 (2) | 2.723 (3) | 169 (4) |
N2—H2A···O2Wiv | 0.88 | 1.94 | 2.818 (3) | 174 |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) −x, −y+1, −z+1; (iii) −x+1/2, y−1/2, −z+1; (iv) −x+1, −y+1, −z+2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—H1W1···O2W | 0.823 (19) | 2.017 (19) | 2.837 (3) | 174 (4) |
O1W—H1W2···O3i | 0.808 (19) | 1.96 (2) | 2.739 (3) | 161 (4) |
O2W—H2W1···O2ii | 0.798 (18) | 1.97 (2) | 2.751 (3) | 167 (4) |
O2W—H2W1···S1ii | 0.798 (18) | 2.92 (3) | 3.602 (2) | 145 (3) |
O2W—H2W2···O2iii | 0.796 (18) | 1.94 (2) | 2.723 (3) | 169 (4) |
N2—H2A···O2Wiv | 0.88 | 1.94 | 2.818 (3) | 174.4 |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) −x+1, −y+1, −z+1; (iii) −x+1/2, y−1/2, −z+1; (iv) −x+1, −y+1, −z+2. |
Acknowledgements
We thank The Office of Naval Research for financial support. RJB wishes to acknowledge the NSF–MRI program (grant CHE-0619278) for funds to purchase the diffractometer.
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The Ni atom lies on an inversion center and is chelated by N1 and O1 of the 2 symmetry equivalent imidazolesulfonate ligands in a plane, and 2 axial water molecules coordinated in an overall octahedral configuration. All of the Ni—O bond lengths (2.083 (2), 2.094 (2) Å) are about the same, and are in the normal range for octahedral coordinated Ni (2.05–2.12 Å). The largest deviation from the 90 ° angles of the octahedron is N1—Ni—O1, a result of the sulfonate group being attached to the imidazole ring. Two additional uncoordinated water molecules are present, but do not lie on any symmetry elements. There are no links other than hydrogen bonds between molecules, in contrast to the analogous unsolvated Cu(II) derivative (Purdy & Butcher, 2011). Hydrogen bonding links all the water molecules and N2, O2, and O3 into an extended structure in all three dimensions.