metal-organic compounds
Tetraaquabis[(1-ammonio-1-phosphonoethyl)phosphonato]zinc(II) tetrahydrate
aInstitute of General and Inorganic Chemistry, NAS Ukraine, Kyiv, prosp. Palladina 32/34, 03680 Ukraine
*Correspondence e-mail: dudco_anatolij@ukr.net
The title compound, [Zn(C2H8NO6P2)2(H2O)4]·4H2O, was synthesized by the reaction of ZnCl2 with 1-aminoethane-1,1-diyldiphosphonic acid in aqueous solution. The contains one-half of the complex and two water molecules of solvation. The Zn atom occupies a special position on an inversion centre. This results in a slightly distorted octahedral coordination environment, which consists of the O atoms from two phosphonic acids and four water molecules. The displays N—H⋯O and O—H⋯O hydrogen bonding, which creates a three-dimensional network.
Related literature
Diphosphonic acids are efficient drugs for the prevention of calcification and the inhibition of bone resorption, see: Matczak-Jon & Videnova-Adrabinska (2005). Diphosphonic acids and their metal complexes are used in the treatment of Pagets disease, osteoporosis and tumoral osteolysis, see: Szabo et al. (2002). For related structures, see: Li et al. (2006, 2007); Lin et al. (2007).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2005); cell SAINT (Bruker, 2005); data reduction: SAINT; 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: publCIF (Westrip, 2009).
Supporting information
10.1107/S1600536809010599/fj2201sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809010599/fj2201Isup2.hkl
10 ml of the 0.01 M ZnCl2 aqueous solution was added to the 10 ml of 0.02 M water solution of 1-aminoethane-1,1-diyldiphosphonic acid. Colorless crystals of title compound were obtained after 2 weeks of slow evaporation of the resulted solution.
H atoms bonded to N and O were located in a difference map and were freely refined with Uiso(H) = 1.2 Ueq of the
Other H atoms which bonded to C were positioned geometrically and refined using a riding model with C—H = 0.98 Å for CH3 [Uiso(H) = 1.5Ueq(C)].Data collection: APEX2 (Bruker, 2005); cell
SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); 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: publCIF (Westrip, 2009).Fig. 1. The title compound showing 50% probability displacement ellipsoids for the non-hydrogen atoms [Symmetry code: (i) -x, 1 - y, 1 - z]. | |
Fig. 2. Crystal packing of title compound, projection along a axis. Dashed lines indicate hydrogen bonds. |
[Zn(C2H8NO6P2)2(H2O)4]·4H2O | Z = 1 |
Mr = 617.57 | F(000) = 320 |
Triclinic, P1 | Dx = 1.866 Mg m−3 |
Hall symbol: -P 1 | Mo Kα radiation, λ = 0.71073 Å |
a = 5.6712 (4) Å | Cell parameters from 2105 reflections |
b = 9.3279 (6) Å | θ = 2.3–25.9° |
c = 10.7009 (7) Å | µ = 1.50 mm−1 |
α = 96.440 (3)° | T = 173 K |
β = 90.788 (3)° | Block, colourless |
γ = 102.080 (3)° | 0.36 × 0.10 × 0.04 mm |
V = 549.65 (6) Å3 |
Bruker APEXII CCD diffractometer | 2244 independent reflections |
Radiation source: fine-focus sealed tube | 1747 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.058 |
Detector resolution: 8.26 pixels mm-1 | θmax = 26.4°, θmin = 2.3° |
ϕ and ω scans | h = −7→7 |
Absorption correction: numerical (SADABS; Bruker, 2005) | k = −11→10 |
Tmin = 0.612, Tmax = 0.945 | l = −13→13 |
8897 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)] = 0.037 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.081 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | w = 1/[σ2(Fo2) + (0.0395P)2] where P = (Fo2 + 2Fc2)/3 |
2244 reflections | (Δ/σ)max < 0.001 |
182 parameters | Δρmax = 0.39 e Å−3 |
1 restraint | Δρmin = −0.48 e Å−3 |
[Zn(C2H8NO6P2)2(H2O)4]·4H2O | γ = 102.080 (3)° |
Mr = 617.57 | V = 549.65 (6) Å3 |
Triclinic, P1 | Z = 1 |
a = 5.6712 (4) Å | Mo Kα radiation |
b = 9.3279 (6) Å | µ = 1.50 mm−1 |
c = 10.7009 (7) Å | T = 173 K |
α = 96.440 (3)° | 0.36 × 0.10 × 0.04 mm |
β = 90.788 (3)° |
Bruker APEXII CCD diffractometer | 2244 independent reflections |
Absorption correction: numerical (SADABS; Bruker, 2005) | 1747 reflections with I > 2σ(I) |
Tmin = 0.612, Tmax = 0.945 | Rint = 0.058 |
8897 measured reflections |
R[F2 > 2σ(F2)] = 0.037 | 1 restraint |
wR(F2) = 0.081 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | Δρmax = 0.39 e Å−3 |
2244 reflections | Δρmin = −0.48 e Å−3 |
182 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 | ||
Zn1 | 0.0000 | 0.5000 | 0.5000 | 0.01171 (16) | |
P1 | 0.02405 (14) | 0.80873 (8) | 0.37915 (7) | 0.01033 (19) | |
P2 | −0.00669 (14) | 0.81048 (9) | 0.09143 (7) | 0.0116 (2) | |
C1 | 0.1808 (5) | 0.8672 (3) | 0.2381 (3) | 0.0109 (6) | |
C2 | 0.2791 (6) | 1.0348 (3) | 0.2544 (3) | 0.0176 (7) | |
H2A | 0.3983 | 1.0614 | 0.3248 | 0.026* | |
H2B | 0.1461 | 1.0855 | 0.2716 | 0.026* | |
H2C | 0.3557 | 1.0644 | 0.1770 | 0.026* | |
N1 | 0.3905 (5) | 0.7921 (3) | 0.2240 (3) | 0.0133 (6) | |
H1A | 0.483 (6) | 0.830 (4) | 0.160 (3) | 0.020* | |
H1B | 0.349 (6) | 0.699 (4) | 0.208 (3) | 0.020* | |
H1C | 0.485 (6) | 0.807 (4) | 0.295 (3) | 0.020* | |
O1 | −0.0090 (4) | 0.6449 (2) | 0.37040 (19) | 0.0135 (5) | |
O2 | 0.2165 (4) | 0.8783 (2) | 0.4886 (2) | 0.0143 (5) | |
H2O | 0.206 (6) | 0.956 (4) | 0.519 (3) | 0.017* | |
O3 | −0.1966 (4) | 0.8741 (2) | 0.39210 (19) | 0.0139 (5) | |
O4 | −0.0857 (4) | 0.6470 (2) | 0.0759 (2) | 0.0181 (5) | |
O5 | 0.1793 (4) | 0.8548 (2) | −0.0123 (2) | 0.0148 (5) | |
H5O | 0.182 (6) | 0.931 (3) | −0.039 (3) | 0.018* | |
O6 | −0.1990 (4) | 0.8997 (2) | 0.0930 (2) | 0.0156 (5) | |
O7 | 0.1908 (4) | 0.3844 (3) | 0.3764 (2) | 0.0183 (5) | |
H71 | 0.319 (7) | 0.371 (4) | 0.408 (3) | 0.022* | |
H72 | 0.204 (7) | 0.413 (4) | 0.312 (4) | 0.022* | |
O8 | 0.3234 (4) | 0.6366 (3) | 0.5883 (2) | 0.0152 (5) | |
H81 | 0.311 (6) | 0.719 (4) | 0.571 (3) | 0.018* | |
H82 | 0.300 (6) | 0.633 (4) | 0.667 (4) | 0.018* | |
O9 | 0.2666 (4) | 0.6106 (3) | 0.8304 (2) | 0.0181 (5) | |
H91 | 0.228 (6) | 0.681 (4) | 0.882 (3) | 0.022* | |
H92 | 0.189 (6) | 0.532 (4) | 0.852 (3) | 0.022* | |
O10 | 0.3107 (4) | 0.4849 (3) | 0.1490 (2) | 0.0187 (5) | |
H101 | 0.236 (6) | 0.448 (4) | 0.079 (4) | 0.022* | |
H102 | 0.437 (7) | 0.460 (4) | 0.143 (3) | 0.022* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Zn1 | 0.0117 (3) | 0.0109 (3) | 0.0129 (3) | 0.0029 (2) | 0.0003 (2) | 0.0021 (2) |
P1 | 0.0105 (4) | 0.0103 (4) | 0.0105 (4) | 0.0031 (3) | 0.0003 (3) | 0.0009 (3) |
P2 | 0.0115 (4) | 0.0125 (4) | 0.0116 (4) | 0.0031 (3) | −0.0009 (3) | 0.0035 (3) |
C1 | 0.0096 (15) | 0.0088 (15) | 0.0146 (16) | 0.0030 (12) | 0.0003 (12) | 0.0007 (12) |
C2 | 0.0208 (18) | 0.0114 (16) | 0.0183 (18) | −0.0021 (13) | 0.0001 (14) | 0.0017 (13) |
N1 | 0.0105 (14) | 0.0155 (15) | 0.0134 (15) | 0.0010 (12) | −0.0017 (11) | 0.0032 (12) |
O1 | 0.0179 (12) | 0.0093 (11) | 0.0133 (12) | 0.0028 (9) | 0.0007 (9) | 0.0011 (8) |
O2 | 0.0164 (12) | 0.0141 (12) | 0.0129 (12) | 0.0067 (10) | −0.0032 (9) | −0.0032 (9) |
O3 | 0.0118 (11) | 0.0150 (12) | 0.0154 (12) | 0.0049 (9) | −0.0013 (9) | −0.0004 (9) |
O4 | 0.0224 (13) | 0.0143 (12) | 0.0158 (12) | 0.0001 (9) | −0.0047 (10) | 0.0013 (9) |
O5 | 0.0187 (12) | 0.0118 (12) | 0.0167 (12) | 0.0061 (10) | 0.0061 (9) | 0.0080 (9) |
O6 | 0.0113 (11) | 0.0206 (12) | 0.0178 (12) | 0.0060 (9) | 0.0024 (9) | 0.0092 (9) |
O7 | 0.0186 (13) | 0.0225 (13) | 0.0162 (13) | 0.0090 (10) | −0.0004 (11) | 0.0043 (10) |
O8 | 0.0146 (12) | 0.0139 (12) | 0.0181 (13) | 0.0034 (10) | −0.0017 (10) | 0.0054 (10) |
O9 | 0.0201 (13) | 0.0148 (12) | 0.0199 (13) | 0.0042 (10) | 0.0041 (10) | 0.0025 (10) |
O10 | 0.0152 (13) | 0.0239 (13) | 0.0176 (13) | 0.0072 (11) | −0.0022 (10) | −0.0004 (10) |
Zn1—O1 | 2.050 (2) | C2—H2A | 0.9800 |
Zn1—O1i | 2.050 (2) | C2—H2B | 0.9800 |
Zn1—O7i | 2.071 (2) | C2—H2C | 0.9800 |
Zn1—O7 | 2.071 (2) | N1—H1A | 0.93 (4) |
Zn1—O8i | 2.141 (2) | N1—H1B | 0.85 (4) |
Zn1—O8 | 2.141 (2) | N1—H1C | 0.90 (4) |
P1—O1 | 1.492 (2) | O2—H2O | 0.78 (3) |
P1—O3 | 1.504 (2) | O5—H5O | 0.793 (18) |
P1—O2 | 1.575 (2) | O7—H71 | 0.84 (4) |
P1—C1 | 1.839 (3) | O7—H72 | 0.76 (4) |
P2—O4 | 1.486 (2) | O8—H81 | 0.82 (4) |
P2—O6 | 1.503 (2) | O8—H82 | 0.86 (4) |
P2—O5 | 1.571 (2) | O9—H91 | 0.87 (4) |
P2—C1 | 1.846 (3) | O9—H92 | 0.83 (4) |
C1—N1 | 1.502 (4) | O10—H101 | 0.85 (4) |
C1—C2 | 1.535 (4) | O10—H102 | 0.80 (4) |
O1—Zn1—O1i | 179.999 (1) | N1—C1—P1 | 107.2 (2) |
O1—Zn1—O7i | 90.77 (9) | C2—C1—P1 | 110.6 (2) |
O1i—Zn1—O7i | 89.23 (9) | N1—C1—P2 | 106.55 (19) |
O1—Zn1—O7 | 89.23 (9) | C2—C1—P2 | 110.3 (2) |
O1i—Zn1—O7 | 90.77 (9) | P1—C1—P2 | 113.58 (16) |
O7i—Zn1—O7 | 180.00 (11) | C1—C2—H2A | 109.5 |
O1—Zn1—O8i | 88.74 (9) | C1—C2—H2B | 109.5 |
O1i—Zn1—O8i | 91.26 (9) | H2A—C2—H2B | 109.5 |
O7i—Zn1—O8i | 92.46 (9) | C1—C2—H2C | 109.5 |
O7—Zn1—O8i | 87.54 (9) | H2A—C2—H2C | 109.5 |
O1—Zn1—O8 | 91.27 (9) | H2B—C2—H2C | 109.5 |
O1i—Zn1—O8 | 88.73 (9) | C1—N1—H1A | 108 (2) |
O7i—Zn1—O8 | 87.54 (9) | C1—N1—H1B | 114 (2) |
O7—Zn1—O8 | 92.46 (9) | H1A—N1—H1B | 110 (3) |
O8i—Zn1—O8 | 180.0 | C1—N1—H1C | 113 (2) |
O1—P1—O3 | 118.11 (12) | H1A—N1—H1C | 108 (3) |
O1—P1—O2 | 107.82 (12) | H1B—N1—H1C | 104 (3) |
O3—P1—O2 | 111.01 (12) | P1—O1—Zn1 | 133.80 (13) |
O1—P1—C1 | 107.13 (13) | P1—O2—H2O | 115 (3) |
O3—P1—C1 | 108.84 (13) | P2—O5—H5O | 118 (3) |
O2—P1—C1 | 102.79 (13) | Zn1—O7—H71 | 113 (2) |
O4—P2—O6 | 117.67 (13) | Zn1—O7—H72 | 114 (3) |
O4—P2—O5 | 108.21 (12) | H71—O7—H72 | 114 (4) |
O6—P2—O5 | 110.56 (12) | Zn1—O8—H81 | 101 (2) |
O4—P2—C1 | 108.34 (13) | Zn1—O8—H82 | 103 (2) |
O6—P2—C1 | 108.52 (13) | H81—O8—H82 | 108 (3) |
O5—P2—C1 | 102.44 (13) | H91—O9—H92 | 106 (3) |
N1—C1—C2 | 108.4 (3) | H101—O10—H102 | 103 (3) |
O1—P1—C1—N1 | −47.7 (2) | O6—P2—C1—C2 | −54.5 (2) |
O3—P1—C1—N1 | −176.47 (18) | O5—P2—C1—C2 | 62.5 (2) |
O2—P1—C1—N1 | 65.8 (2) | O4—P2—C1—P1 | −58.45 (19) |
O1—P1—C1—C2 | −165.7 (2) | O6—P2—C1—P1 | 70.38 (18) |
O3—P1—C1—C2 | 65.6 (2) | O5—P2—C1—P1 | −172.68 (15) |
O2—P1—C1—C2 | −52.2 (2) | O3—P1—O1—Zn1 | −92.94 (19) |
O1—P1—C1—P2 | 69.67 (18) | O2—P1—O1—Zn1 | 33.8 (2) |
O3—P1—C1—P2 | −59.08 (18) | C1—P1—O1—Zn1 | 143.85 (17) |
O2—P1—C1—P2 | −176.85 (15) | O7i—Zn1—O1—P1 | 41.88 (18) |
O4—P2—C1—N1 | 59.3 (2) | O7—Zn1—O1—P1 | −138.12 (18) |
O6—P2—C1—N1 | −171.88 (19) | O8i—Zn1—O1—P1 | 134.32 (18) |
O5—P2—C1—N1 | −54.9 (2) | O8—Zn1—O1—P1 | −45.68 (18) |
O4—P2—C1—C2 | 176.7 (2) |
Symmetry code: (i) −x, −y+1, −z+1. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O6ii | 0.93 (4) | 1.96 (4) | 2.796 (4) | 150 (3) |
N1—H1B···O10 | 0.85 (4) | 1.99 (4) | 2.827 (4) | 168 (3) |
N1—H1C···O3ii | 0.90 (4) | 2.01 (4) | 2.851 (3) | 153 (3) |
O2—H2O···O3iii | 0.78 (3) | 1.76 (3) | 2.536 (3) | 172 (4) |
O5—H5O···O6iv | 0.79 (2) | 1.73 (2) | 2.519 (3) | 177 (4) |
O7—H71···O8v | 0.84 (4) | 2.05 (4) | 2.826 (3) | 155 (3) |
O7—H72···O10 | 0.76 (4) | 2.00 (4) | 2.748 (3) | 168 (4) |
O8—H81···O2 | 0.82 (4) | 1.97 (4) | 2.772 (3) | 163 (3) |
O8—H82···O9 | 0.86 (4) | 1.79 (4) | 2.646 (3) | 174 (3) |
O9—H91···O5vi | 0.87 (4) | 1.94 (4) | 2.810 (3) | 172 (3) |
O9—H92···O4i | 0.83 (4) | 1.91 (4) | 2.715 (3) | 165 (4) |
O10—H101···O4vii | 0.85 (4) | 1.90 (4) | 2.744 (3) | 175 (3) |
O10—H102···O9v | 0.80 (4) | 1.96 (4) | 2.741 (3) | 167 (4) |
Symmetry codes: (i) −x, −y+1, −z+1; (ii) x+1, y, z; (iii) −x, −y+2, −z+1; (iv) −x, −y+2, −z; (v) −x+1, −y+1, −z+1; (vi) x, y, z+1; (vii) −x, −y+1, −z. |
Experimental details
Crystal data | |
Chemical formula | [Zn(C2H8NO6P2)2(H2O)4]·4H2O |
Mr | 617.57 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 173 |
a, b, c (Å) | 5.6712 (4), 9.3279 (6), 10.7009 (7) |
α, β, γ (°) | 96.440 (3), 90.788 (3), 102.080 (3) |
V (Å3) | 549.65 (6) |
Z | 1 |
Radiation type | Mo Kα |
µ (mm−1) | 1.50 |
Crystal size (mm) | 0.36 × 0.10 × 0.04 |
Data collection | |
Diffractometer | Bruker APEXII CCD diffractometer |
Absorption correction | Numerical (SADABS; Bruker, 2005) |
Tmin, Tmax | 0.612, 0.945 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8897, 2244, 1747 |
Rint | 0.058 |
(sin θ/λ)max (Å−1) | 0.626 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.081, 1.00 |
No. of reflections | 2244 |
No. of parameters | 182 |
No. of restraints | 1 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.39, −0.48 |
Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SAINT (Bruker, 2005), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008), publCIF (Westrip, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1A···O6i | 0.93 (4) | 1.96 (4) | 2.796 (4) | 150 (3) |
N1—H1B···O10 | 0.85 (4) | 1.99 (4) | 2.827 (4) | 168 (3) |
N1—H1C···O3i | 0.90 (4) | 2.01 (4) | 2.851 (3) | 153 (3) |
O2—H2O···O3ii | 0.78 (3) | 1.76 (3) | 2.536 (3) | 172 (4) |
O5—H5O···O6iii | 0.793 (18) | 1.726 (19) | 2.519 (3) | 177 (4) |
O7—H71···O8iv | 0.84 (4) | 2.05 (4) | 2.826 (3) | 155 (3) |
O7—H72···O10 | 0.76 (4) | 2.00 (4) | 2.748 (3) | 168 (4) |
O8—H81···O2 | 0.82 (4) | 1.97 (4) | 2.772 (3) | 163 (3) |
O8—H82···O9 | 0.86 (4) | 1.79 (4) | 2.646 (3) | 174 (3) |
O9—H91···O5v | 0.87 (4) | 1.94 (4) | 2.810 (3) | 172 (3) |
O9—H92···O4vi | 0.83 (4) | 1.91 (4) | 2.715 (3) | 165 (4) |
O10—H101···O4vii | 0.85 (4) | 1.90 (4) | 2.744 (3) | 175 (3) |
O10—H102···O9iv | 0.80 (4) | 1.96 (4) | 2.741 (3) | 167 (4) |
Symmetry codes: (i) x+1, y, z; (ii) −x, −y+2, −z+1; (iii) −x, −y+2, −z; (iv) −x+1, −y+1, −z+1; (v) x, y, z+1; (vi) −x, −y+1, −z+1; (vii) −x, −y+1, −z. |
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Organic diphosphonic acids are potentially very powerful chelating agents used in metal extractions and are tested by the pharmaceutical industry for use as efficient drugs preventing calcification and inhibiting bone resorption (Matczak-Jon et al., 2005). Diphosphonic acids and their metal complexes are used in the treatment of Pagets disease, osteoporosis and tumoral osteolysis (Szabo et al., 2002). The asymmetric unit of title compound contains one-half of the formula unit (Fig.1); Zn atom occupy special position at the inversion centre and creates a slightly distorted octahedral coordination environment, which consist of two phosphonic and four aqueous oxygen atoms. The coordinated diphosphonic acids residue exist as zwitterions with positive charge on NH3 group and negative on the oxygen atom of the non-coordinated phosphonic group. The crystal structure displays N—H···O and O—H···O hydrogen bonding, which creates a three-dimensional network (Table 1, Fig.2).