Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807020569/rz2135sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807020569/rz2135Isup2.hkl |
CCDC reference: 650509
Key indicators
- Single-crystal X-ray study
- T = 298 K
- Mean (C-C) = 0.003 Å
- R factor = 0.029
- wR factor = 0.073
- Data-to-parameter ratio = 15.6
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ .... ? PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X) Ni1 - O1W .. 5.34 su PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........ 4
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 3 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 1 ALERT type 2 Indicator that the structure model may be wrong or deficient 0 ALERT type 3 Indicator that the structure quality may be low 1 ALERT type 4 Improvement, methodology, query or suggestion 0 ALERT type 5 Informative message, check
Nickel chloride hexahydrate (0.072 g, 0.3 mmol) and citric acid monohydrate (0.061 g, 0.3 mmol) were dissolved in water/ethanol (1:1 v/v) solution (5 ml). Piperazine hexahydrate (0.096 g, 0.5 mmol) was then added and the solution stirred for 30 min. The resulting solution was transferred into Teflon-lined autoclave and heated at 130 °C under autogenous pressure for 5 days. Green block crystals suitable for X-ray analysis were collected from the reaction mixture.
The structure was solved by Patterson method. All hydrogen atoms were included in the riding model approximation, with C–H = 0.97 Å, N–H = 0.90 Å, O–H = 0.85 Å, and with Uiso(H) = 1.2 Ueq(C, N, O).
Up to now, hundreds of metal citrate complexes with diverse architectures have been synthesized and well documented in the literature (Kaliva et al., 2004; Kefalas et al., 2005; Wang et al., 2005; Xiang et al., 2005; Zhang et al., 2006). Some complexes contain centrosymmetric dimers with 1-D polymeric chain or 2-D layer structure (Zhou et al., 2005; Baggio & Perec, 2004), some are similar to the title complex (Baker et al., 1983; Kotsakis et al., 2003), most of them have monovalent counter ions. In this paper, the complex we report has a divalent organic piperazinium cation. Its structure is shown in Fig. 1. Each citrate ligand is triply deprotonated, and chelates to the Ni atom through the α-hydroxyl, α-carboxyl and one β-carboxyl oxygen atom. The other β-carboxyl oxygen atom spans over to the second Ni atom of the dimer. The distorted octahedral coordination sphere of each nickel atom is completed by the oxygen atoms of two water molecules. Selected geometric parameters of the complex are given in Table 1. The piperazinium cations occupy the space between the nickel-citrate dimers. The anions and the cations are connected by strong N—H···O hydrogen bonds. There are intramolecular hydrogen bonds between the hydroxyl groups and the carboxyl groups. Hydrogen bonding interactions are also observed between the coordinated water molecules and the carboxyl groups of neighbouring anions, forming a three-dimensional network (Table 2, Fig. 2).
For related literature, see: Baggio & Perec (2004); Baker et al. (1983); Kaliva et al. (2004); Kefalas et al. (2005); Kotsakis et al. (2003); Wang et al. (2005); Xiang et al. (2005); Zhang et al. (2006); Zhou et al. (2005).
Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO; data reduction: RAPID-AUTO; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL/PC (Sheldrick, 1993); software used to prepare material for publication: SHELXL97.
(C4H12N2)[Ni2(C6H5O7)2(H2O)4] | F(000) = 680 |
Mr = 655.80 | Dx = 1.869 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 9899 reflections |
a = 13.342 (3) Å | θ = 3.0–27.6° |
b = 6.7054 (13) Å | µ = 1.71 mm−1 |
c = 13.613 (3) Å | T = 298 K |
β = 106.93 (3)° | Block, green |
V = 1165.1 (5) Å3 | 0.20 × 0.18 × 0.15 mm |
Z = 2 |
Rigaku R-AXIS RAPID diffractometer | 2462 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.046 |
Graphite monochromator | θmax = 27.5°, θmin = 3.1° |
Oscillation scans | h = −17→17 |
10894 measured reflections | k = −8→8 |
2677 independent reflections | l = −17→17 |
Refinement on F2 | Primary atom site location: patt |
Least-squares matrix: full | Secondary atom site location: difference Fourier map |
R[F2 > 2σ(F2)] = 0.029 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.073 | H-atom parameters constrained |
S = 1.08 | w = 1/[σ2(Fo2) + (0.033P)2 + 0.5209P] where P = (Fo2 + 2Fc2)/3 |
2677 reflections | (Δ/σ)max < 0.001 |
172 parameters | Δρmax = 0.36 e Å−3 |
0 restraints | Δρmin = −0.58 e Å−3 |
(C4H12N2)[Ni2(C6H5O7)2(H2O)4] | V = 1165.1 (5) Å3 |
Mr = 655.80 | Z = 2 |
Monoclinic, P21/n | Mo Kα radiation |
a = 13.342 (3) Å | µ = 1.71 mm−1 |
b = 6.7054 (13) Å | T = 298 K |
c = 13.613 (3) Å | 0.20 × 0.18 × 0.15 mm |
β = 106.93 (3)° |
Rigaku R-AXIS RAPID diffractometer | 2462 reflections with I > 2σ(I) |
10894 measured reflections | Rint = 0.046 |
2677 independent reflections |
R[F2 > 2σ(F2)] = 0.029 | 0 restraints |
wR(F2) = 0.073 | H-atom parameters constrained |
S = 1.08 | Δρmax = 0.36 e Å−3 |
2677 reflections | Δρmin = −0.58 e Å−3 |
172 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 | ||
Ni1 | 0.356449 (16) | 0.10184 (3) | 0.089492 (15) | 0.01502 (9) | |
O1 | 0.46895 (9) | 0.27879 (17) | 0.05413 (8) | 0.0168 (2) | |
H1 | 0.4979 | 0.2121 | 0.0167 | 0.020* | |
O1W | 0.21588 (10) | 0.1791 (2) | −0.01518 (10) | 0.0267 (3) | |
H1WA | 0.2010 | 0.0965 | −0.0647 | 0.032* | |
H1WB | 0.2207 | 0.2945 | −0.0392 | 0.032* | |
O2 | 0.48547 (10) | 0.00460 (18) | 0.19579 (9) | 0.0210 (3) | |
O2W | 0.26483 (10) | −0.07943 (18) | 0.14890 (10) | 0.0215 (3) | |
H2WB | 0.2269 | −0.0091 | 0.1760 | 0.026* | |
H2WA | 0.3034 | −0.1542 | 0.1951 | 0.026* | |
O3 | 0.62422 (12) | 0.1371 (2) | 0.30710 (10) | 0.0308 (3) | |
O4 | 0.34262 (10) | 0.33467 (19) | 0.18366 (10) | 0.0225 (3) | |
O5 | 0.38093 (11) | 0.60449 (18) | 0.27900 (11) | 0.0247 (3) | |
O6 | 0.62307 (10) | 0.11233 (19) | 0.00955 (10) | 0.0239 (3) | |
O7 | 0.78853 (11) | 0.1785 (2) | 0.09831 (11) | 0.0329 (3) | |
N1 | 0.00054 (13) | 0.3898 (2) | 0.09153 (11) | 0.0207 (3) | |
H1A | 0.0278 | 0.2936 | 0.1377 | 0.025* | |
H1B | −0.0523 | 0.4481 | 0.1095 | 0.025* | |
C1 | 0.54617 (13) | 0.3207 (2) | 0.15133 (12) | 0.0155 (3) | |
C2 | 0.55405 (13) | 0.1389 (2) | 0.22351 (12) | 0.0165 (3) | |
C3 | 0.50727 (14) | 0.5019 (2) | 0.19770 (13) | 0.0191 (3) | |
H3A | 0.5601 | 0.5372 | 0.2610 | 0.023* | |
H3B | 0.5008 | 0.6132 | 0.1507 | 0.023* | |
C4 | 0.40335 (14) | 0.4756 (2) | 0.22078 (13) | 0.0172 (3) | |
C5 | 0.65218 (14) | 0.3690 (3) | 0.13446 (14) | 0.0200 (3) | |
H5A | 0.6457 | 0.4922 | 0.0958 | 0.024* | |
H5B | 0.7032 | 0.3910 | 0.2007 | 0.024* | |
C6 | 0.69299 (14) | 0.2077 (3) | 0.07807 (12) | 0.0193 (3) | |
C7 | 0.08284 (14) | 0.5411 (3) | 0.09266 (13) | 0.0226 (4) | |
H7A | 0.1424 | 0.4760 | 0.0792 | 0.027* | |
H7B | 0.1065 | 0.6024 | 0.1600 | 0.027* | |
C8 | 0.04050 (15) | 0.7003 (3) | 0.01229 (13) | 0.0227 (4) | |
H8A | −0.0152 | 0.7730 | 0.0291 | 0.027* | |
H8B | 0.0959 | 0.7941 | 0.0123 | 0.027* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Ni1 | 0.01363 (13) | 0.01736 (13) | 0.01496 (13) | −0.00038 (8) | 0.00552 (9) | −0.00189 (8) |
O1 | 0.0153 (5) | 0.0214 (6) | 0.0144 (5) | 0.0000 (5) | 0.0054 (4) | −0.0003 (5) |
O1W | 0.0247 (7) | 0.0296 (7) | 0.0237 (6) | 0.0077 (6) | 0.0039 (5) | 0.0015 (6) |
O2 | 0.0214 (6) | 0.0190 (6) | 0.0206 (6) | −0.0021 (5) | 0.0029 (5) | 0.0026 (5) |
O2W | 0.0207 (6) | 0.0231 (6) | 0.0238 (6) | 0.0001 (5) | 0.0112 (5) | 0.0014 (5) |
O3 | 0.0296 (7) | 0.0320 (7) | 0.0225 (6) | −0.0021 (6) | −0.0056 (6) | 0.0017 (6) |
O4 | 0.0202 (6) | 0.0222 (6) | 0.0286 (6) | −0.0044 (5) | 0.0123 (5) | −0.0088 (6) |
O5 | 0.0268 (7) | 0.0219 (6) | 0.0306 (7) | −0.0042 (5) | 0.0168 (6) | −0.0100 (5) |
O6 | 0.0162 (6) | 0.0321 (7) | 0.0240 (6) | −0.0009 (5) | 0.0067 (5) | −0.0123 (5) |
O7 | 0.0160 (6) | 0.0441 (8) | 0.0376 (7) | 0.0008 (6) | 0.0062 (6) | −0.0163 (7) |
N1 | 0.0228 (8) | 0.0223 (7) | 0.0181 (7) | 0.0029 (6) | 0.0078 (6) | 0.0051 (6) |
C1 | 0.0142 (7) | 0.0168 (7) | 0.0163 (7) | −0.0022 (6) | 0.0056 (6) | −0.0041 (6) |
C2 | 0.0158 (8) | 0.0181 (7) | 0.0158 (7) | 0.0020 (7) | 0.0051 (6) | −0.0027 (6) |
C3 | 0.0194 (8) | 0.0158 (7) | 0.0244 (8) | −0.0016 (7) | 0.0101 (7) | −0.0048 (7) |
C4 | 0.0188 (8) | 0.0158 (7) | 0.0183 (7) | 0.0021 (7) | 0.0075 (6) | 0.0011 (6) |
C5 | 0.0181 (8) | 0.0207 (8) | 0.0232 (8) | −0.0043 (7) | 0.0092 (7) | −0.0058 (7) |
C6 | 0.0175 (8) | 0.0237 (8) | 0.0185 (7) | −0.0018 (7) | 0.0080 (7) | −0.0019 (7) |
C7 | 0.0211 (8) | 0.0272 (9) | 0.0181 (8) | −0.0022 (8) | 0.0032 (7) | −0.0014 (7) |
C8 | 0.0258 (9) | 0.0197 (8) | 0.0235 (8) | −0.0034 (7) | 0.0085 (7) | −0.0018 (7) |
Ni1—O2 | 2.0078 (14) | N1—C8ii | 1.487 (2) |
Ni1—O6i | 2.0419 (13) | N1—C7 | 1.492 (2) |
Ni1—O2W | 2.0498 (13) | N1—H1A | 0.9000 |
Ni1—O4 | 2.0622 (12) | N1—H1B | 0.9000 |
Ni1—O1W | 2.0638 (15) | C1—C3 | 1.528 (2) |
Ni1—O1 | 2.0769 (12) | C1—C5 | 1.532 (2) |
O1—C1 | 1.448 (2) | C1—C2 | 1.550 (2) |
O1—H1 | 0.8499 | C3—C4 | 1.519 (2) |
O1W—H1WA | 0.8501 | C3—H3A | 0.9700 |
O1W—H1WB | 0.8500 | C3—H3B | 0.9700 |
O2—C2 | 1.261 (2) | C5—C6 | 1.516 (2) |
O2W—H2WB | 0.8501 | C5—H5A | 0.9700 |
O2W—H2WA | 0.8499 | C5—H5B | 0.9700 |
O3—C2 | 1.245 (2) | C7—C8 | 1.515 (3) |
O4—C4 | 1.252 (2) | C7—H7A | 0.9700 |
O5—C4 | 1.266 (2) | C7—H7B | 0.9700 |
O6—C6 | 1.281 (2) | C8—N1ii | 1.487 (2) |
O6—Ni1i | 2.0419 (12) | C8—H8A | 0.9700 |
O7—C6 | 1.239 (2) | C8—H8B | 0.9700 |
O2—Ni1—O6i | 89.77 (6) | O1—C1—C2 | 108.98 (13) |
O2—Ni1—O2W | 90.44 (5) | C3—C1—C2 | 109.40 (13) |
O6i—Ni1—O2W | 93.06 (6) | C5—C1—C2 | 111.48 (14) |
O2—Ni1—O4 | 90.63 (5) | O3—C2—O2 | 123.64 (16) |
O6i—Ni1—O4 | 175.09 (5) | O3—C2—C1 | 118.72 (15) |
O2W—Ni1—O4 | 91.84 (5) | O2—C2—C1 | 117.56 (14) |
O2—Ni1—O1W | 174.29 (5) | C4—C3—C1 | 115.69 (14) |
O6i—Ni1—O1W | 89.43 (6) | C4—C3—H3A | 108.4 |
O2W—Ni1—O1W | 83.96 (6) | C1—C3—H3A | 108.4 |
O4—Ni1—O1W | 90.65 (6) | C4—C3—H3B | 108.4 |
O2—Ni1—O1 | 80.03 (5) | C1—C3—H3B | 108.4 |
O6i—Ni1—O1 | 90.23 (5) | H3A—C3—H3B | 107.4 |
O2W—Ni1—O1 | 169.91 (5) | O4—C4—O5 | 121.66 (16) |
O4—Ni1—O1 | 85.02 (5) | O4—C4—C3 | 121.80 (15) |
O1W—Ni1—O1 | 105.63 (5) | O5—C4—C3 | 116.54 (15) |
C1—O1—Ni1 | 105.60 (9) | C6—C5—C1 | 114.11 (14) |
C1—O1—H1 | 108.9 | C6—C5—H5A | 108.7 |
Ni1—O1—H1 | 108.8 | C1—C5—H5A | 108.7 |
Ni1—O1W—H1WA | 109.8 | C6—C5—H5B | 108.7 |
Ni1—O1W—H1WB | 109.8 | C1—C5—H5B | 108.7 |
H1WA—O1W—H1WB | 108.3 | H5A—C5—H5B | 107.6 |
C2—O2—Ni1 | 112.28 (11) | O7—C6—O6 | 124.52 (16) |
Ni1—O2W—H2WB | 109.9 | O7—C6—C5 | 119.87 (16) |
Ni1—O2W—H2WA | 109.8 | O6—C6—C5 | 115.59 (15) |
H2WB—O2W—H2WA | 108.4 | N1—C7—C8 | 110.69 (15) |
C4—O4—Ni1 | 131.14 (11) | N1—C7—H7A | 109.5 |
C6—O6—Ni1i | 128.50 (12) | C8—C7—H7A | 109.5 |
C8ii—N1—C7 | 110.63 (14) | N1—C7—H7B | 109.5 |
C8ii—N1—H1A | 109.5 | C8—C7—H7B | 109.5 |
C7—N1—H1A | 109.5 | H7A—C7—H7B | 108.1 |
C8ii—N1—H1B | 109.5 | N1ii—C8—C7 | 110.87 (14) |
C7—N1—H1B | 109.5 | N1ii—C8—H8A | 109.5 |
H1A—N1—H1B | 108.1 | C7—C8—H8A | 109.5 |
O1—C1—C3 | 107.15 (13) | N1ii—C8—H8B | 109.5 |
O1—C1—C5 | 110.25 (13) | C7—C8—H8B | 109.5 |
C3—C1—C5 | 109.47 (14) | H8A—C8—H8B | 108.1 |
Symmetry codes: (i) −x+1, −y, −z; (ii) −x, −y+1, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···O6 | 0.85 | 1.83 | 2.5632 (18) | 144 |
O1W—H1WA···O7i | 0.85 | 1.91 | 2.645 (2) | 143 |
O2W—H2WB···O5iii | 0.85 | 1.88 | 2.7163 (19) | 167 |
O2W—H2WA···O5iv | 0.85 | 2.08 | 2.903 (2) | 165 |
N1—H1A···O5iii | 0.90 | 1.89 | 2.765 (2) | 163 |
N1—H1B···O3v | 0.90 | 2.11 | 2.960 (2) | 157 |
Symmetry codes: (i) −x+1, −y, −z; (iii) −x+1/2, y−1/2, −z+1/2; (iv) x, y−1, z; (v) −x+1/2, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | (C4H12N2)[Ni2(C6H5O7)2(H2O)4] |
Mr | 655.80 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 298 |
a, b, c (Å) | 13.342 (3), 6.7054 (13), 13.613 (3) |
β (°) | 106.93 (3) |
V (Å3) | 1165.1 (5) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 1.71 |
Crystal size (mm) | 0.20 × 0.18 × 0.15 |
Data collection | |
Diffractometer | Rigaku R-AXIS RAPID |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10894, 2677, 2462 |
Rint | 0.046 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.029, 0.073, 1.08 |
No. of reflections | 2677 |
No. of parameters | 172 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.36, −0.58 |
Computer programs: RAPID-AUTO (Rigaku, 1998), RAPID-AUTO, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL/PC (Sheldrick, 1993), SHELXL97.
Ni1—O2 | 2.0078 (14) | Ni1—O4 | 2.0622 (12) |
Ni1—O6i | 2.0419 (13) | Ni1—O1W | 2.0638 (15) |
Ni1—O2W | 2.0498 (13) | Ni1—O1 | 2.0769 (12) |
O2—Ni1—O6i | 89.77 (6) | O2W—Ni1—O1W | 83.96 (6) |
O2—Ni1—O2W | 90.44 (5) | O4—Ni1—O1W | 90.65 (6) |
O6i—Ni1—O2W | 93.06 (6) | O2—Ni1—O1 | 80.03 (5) |
O2—Ni1—O4 | 90.63 (5) | O6i—Ni1—O1 | 90.23 (5) |
O6i—Ni1—O4 | 175.09 (5) | O2W—Ni1—O1 | 169.91 (5) |
O2W—Ni1—O4 | 91.84 (5) | O4—Ni1—O1 | 85.02 (5) |
O2—Ni1—O1W | 174.29 (5) | O1W—Ni1—O1 | 105.63 (5) |
O6i—Ni1—O1W | 89.43 (6) |
Symmetry code: (i) −x+1, −y, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1···O6 | 0.85 | 1.83 | 2.5632 (18) | 143.7 |
O1W—H1WA···O7i | 0.85 | 1.91 | 2.645 (2) | 143.2 |
O2W—H2WB···O5ii | 0.85 | 1.88 | 2.7163 (19) | 166.9 |
O2W—H2WA···O5iii | 0.85 | 2.08 | 2.903 (2) | 164.6 |
N1—H1A···O5ii | 0.90 | 1.89 | 2.765 (2) | 163.4 |
N1—H1B···O3iv | 0.90 | 2.11 | 2.960 (2) | 157.3 |
Symmetry codes: (i) −x+1, −y, −z; (ii) −x+1/2, y−1/2, −z+1/2; (iii) x, y−1, z; (iv) −x+1/2, y+1/2, −z+1/2. |
Up to now, hundreds of metal citrate complexes with diverse architectures have been synthesized and well documented in the literature (Kaliva et al., 2004; Kefalas et al., 2005; Wang et al., 2005; Xiang et al., 2005; Zhang et al., 2006). Some complexes contain centrosymmetric dimers with 1-D polymeric chain or 2-D layer structure (Zhou et al., 2005; Baggio & Perec, 2004), some are similar to the title complex (Baker et al., 1983; Kotsakis et al., 2003), most of them have monovalent counter ions. In this paper, the complex we report has a divalent organic piperazinium cation. Its structure is shown in Fig. 1. Each citrate ligand is triply deprotonated, and chelates to the Ni atom through the α-hydroxyl, α-carboxyl and one β-carboxyl oxygen atom. The other β-carboxyl oxygen atom spans over to the second Ni atom of the dimer. The distorted octahedral coordination sphere of each nickel atom is completed by the oxygen atoms of two water molecules. Selected geometric parameters of the complex are given in Table 1. The piperazinium cations occupy the space between the nickel-citrate dimers. The anions and the cations are connected by strong N—H···O hydrogen bonds. There are intramolecular hydrogen bonds between the hydroxyl groups and the carboxyl groups. Hydrogen bonding interactions are also observed between the coordinated water molecules and the carboxyl groups of neighbouring anions, forming a three-dimensional network (Table 2, Fig. 2).