Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270109028005/fg3110sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270109028005/fg3110Isup2.hkl |
CCDC reference: 746047
A methanol solution (10 ml) of Cu(CH3COO)2.H2O (0.40 g, 2.0 mmol) was mixed with a methanol solution (5 ml) of 2-picolinic acid (0.25 g, 2.0 mmol), followed by the addition of imidazole (0.14 g, 2.0 mmol) dissolved in methanol (5 ml). The resulting dark-blue solution was left to stand at room temperature. Dark-blue [Green in CIF tables - please check] single crystals suitable for X-ray diffraction were obtained by slow evaporation of the solvent after several days (yield 82%). Elemental analysis: C11H14.76CuN3O5.88 (346.55), calculated: C 38.11, H 4.29, N 12.12; found: C 38.31, H 3.55, N 12.29%. IR (KBr, ν, cm-1): 3432 (OH), 3135 (NH), 2939 (CH), 1623 (CO and CC), 1387 (CH).
H atoms for aromatic CH and methyl CH3 groups were positioned geometrically (C—H = 0.94 Å for aromatic and C—H = 0.97 Å for methyl H atoms) and refined using a riding model, with Uiso(H) = 1.2Ueq(CH) or 1.5Ueq(methyl C). H atoms on the aqua ligand and on the imidazole N atom were found and refined with Uiso(H) = 1.5Ueq(O,N). The O—H bond distance of one H atom on each aqua ligand had to be controlled through a DFIX restraint (SHELXL97; Sheldrick, 2008), with O—H = 0.90 (5) Å. [Sandy: The solvent water H atoms don't seem to have been included in the _sum formula]
Data collection: APEX2 (Bruker, 2006); cell refinement: SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2009); software used to prepare material for publication: publCIF (Westrip, 2009).
[Cu(C6H4NO2)(C2H3O2)(C3H4N2)(H2O)]·0.87H2O | F(000) = 1422 |
Mr = 346.44 | Dx = 1.639 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 4430 reflections |
a = 15.5708 (13) Å | θ = 2.8–25.0° |
b = 6.5334 (5) Å | µ = 1.59 mm−1 |
c = 29.437 (2) Å | T = 203 K |
β = 110.333 (5)° | Isometric, blue |
V = 2808.0 (4) Å3 | 0.21 × 0.15 × 0.04 mm |
Z = 8 |
Bruker APEXII CCD area-detector diffractometer | 5430 independent reflections |
Radiation source: sealed tube | 3948 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.049 |
ω scans | θmax = 25.9°, θmin = 1.4° |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | h = −19→19 |
Tmin = 0.731, Tmax = 0.941 | k = −8→8 |
30383 measured reflections | l = −36→36 |
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)] = 0.035 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.096 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | w = 1/[σ2(Fo2) + (0.0449P)2 + 0.4344P] where P = (Fo2 + 2Fc2)/3 |
5430 reflections | (Δ/σ)max = 0.002 |
421 parameters | Δρmax = 0.36 e Å−3 |
2 restraints | Δρmin = −0.46 e Å−3 |
[Cu(C6H4NO2)(C2H3O2)(C3H4N2)(H2O)]·0.87H2O | V = 2808.0 (4) Å3 |
Mr = 346.44 | Z = 8 |
Monoclinic, P21/c | Mo Kα radiation |
a = 15.5708 (13) Å | µ = 1.59 mm−1 |
b = 6.5334 (5) Å | T = 203 K |
c = 29.437 (2) Å | 0.21 × 0.15 × 0.04 mm |
β = 110.333 (5)° |
Bruker APEXII CCD area-detector diffractometer | 5430 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 1996) | 3948 reflections with I > 2σ(I) |
Tmin = 0.731, Tmax = 0.941 | Rint = 0.049 |
30383 measured reflections |
R[F2 > 2σ(F2)] = 0.035 | 2 restraints |
wR(F2) = 0.096 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | Δρmax = 0.36 e Å−3 |
5430 reflections | Δρmin = −0.46 e Å−3 |
421 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. The crystal water molecules O6 and O26 are only partially occupied and disordered over two positions A and B, each. Occupation factors were refined individually to about 0.63 (2) for the A and 0.24 (2) for the B positions giving an occupancy of about 0.87 for each water molecule. This disorder leads to ALERT levels A and B because of apparent short O···O contacts, in particular a short O6B···O26B contact as ALERT level A. However, only the positions O6A - O26A, O6A - O26B and O26A - O6B can be occupied simultaneously, but not O6A and O6B, O26A and O26B and the noted O6B and O26B. Taking this disorder into account resolves the ALERT level A. ALERT level B concerns apparent short O···O contacts where no hydrogen bonds are present. H atoms of the disordered crystal water molecules were neither found nor refined and could not be calculated. Yet, the short inter O···O contacts are all within a hydrogen-bonding range. Pseudo-symmetry elements were detected with ADDSYM by Chester CHECKCIF routines (ALERT level B) and by PLATON. Refinement could also be carried out in the space group C2/c. Yet, a large number of 4678 systematic absence violations including some stronger reflections were then noted. Also, a tilt disorder would then occur in the aromatic ring of the picolinato group. |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
Cu1 | 0.01495 (2) | 0.13836 (5) | 0.641748 (10) | 0.02639 (11) | |
O1 | −0.04407 (13) | 0.1499 (3) | 0.57198 (7) | 0.0363 (5) | |
O2 | −0.05073 (16) | 0.4855 (3) | 0.57431 (8) | 0.0578 (6) | |
C1 | −0.1058 (3) | 0.3207 (6) | 0.49728 (12) | 0.0691 (11) | |
H1A | −0.1317 | 0.4539 | 0.4856 | 0.104* | |
H1B | −0.1538 | 0.2180 | 0.4874 | 0.104* | |
H1C | −0.0589 | 0.2876 | 0.4838 | 0.104* | |
C2 | −0.0639 (2) | 0.3249 (5) | 0.55212 (10) | 0.0395 (7) | |
O3 | 0.02970 (15) | −0.2227 (3) | 0.64563 (7) | 0.0359 (5) | |
H3A | 0.003 (2) | −0.299 (5) | 0.6239 (12) | 0.054* | |
H3B | 0.022 (2) | −0.273 (5) | 0.6670 (11) | 0.054* | |
N1 | 0.13653 (15) | 0.1873 (3) | 0.63853 (8) | 0.0280 (5) | |
N2 | 0.28613 (16) | 0.2162 (4) | 0.66223 (9) | 0.0332 (6) | |
H2 | 0.339 (2) | 0.225 (5) | 0.6789 (11) | 0.050* | |
C3 | 0.16382 (19) | 0.1784 (4) | 0.59854 (10) | 0.0315 (6) | |
H3 | 0.1245 | 0.1626 | 0.5663 | 0.038* | |
C4 | 0.25605 (19) | 0.1960 (4) | 0.61322 (10) | 0.0348 (6) | |
H4 | 0.2922 | 0.1946 | 0.5934 | 0.042* | |
C5 | 0.21322 (17) | 0.2117 (4) | 0.67618 (10) | 0.0300 (6) | |
H5 | 0.2159 | 0.2242 | 0.7085 | 0.036* | |
N3 | −0.10355 (14) | 0.1332 (3) | 0.65406 (8) | 0.0276 (5) | |
C6 | −0.18899 (18) | 0.1295 (4) | 0.62210 (10) | 0.0318 (6) | |
H6 | −0.1979 | 0.1352 | 0.5889 | 0.038* | |
C7 | −0.26473 (18) | 0.1176 (4) | 0.63618 (11) | 0.0338 (6) | |
H7 | −0.3241 | 0.1181 | 0.6129 | 0.041* | |
C8 | −0.25204 (19) | 0.1050 (4) | 0.68468 (10) | 0.0363 (7) | |
H8 | −0.3026 | 0.0952 | 0.6950 | 0.044* | |
C9 | −0.16380 (18) | 0.1069 (4) | 0.71813 (10) | 0.0324 (6) | |
H9 | −0.1534 | 0.0972 | 0.7515 | 0.039* | |
C10 | −0.09148 (17) | 0.1234 (4) | 0.70156 (9) | 0.0269 (6) | |
C11 | 0.00731 (17) | 0.1286 (4) | 0.73458 (9) | 0.0268 (6) | |
O4 | 0.06603 (12) | 0.1380 (3) | 0.71380 (6) | 0.0304 (4) | |
O5 | 0.02501 (12) | 0.1231 (3) | 0.77895 (6) | 0.0333 (4) | |
Cu2 | 0.47722 (2) | 0.13803 (5) | 0.861393 (10) | 0.02570 (11) | |
O21 | 0.53677 (13) | 0.1507 (3) | 0.93119 (6) | 0.0353 (5) | |
O22 | 0.5378 (2) | 0.4847 (4) | 0.92529 (8) | 0.0727 (8) | |
C21 | 0.6055 (3) | 0.3344 (6) | 1.00374 (12) | 0.0740 (12) | |
H21A | 0.6358 | 0.4655 | 1.0129 | 0.111* | |
H21B | 0.6506 | 0.2256 | 1.0132 | 0.111* | |
H21C | 0.5614 | 0.3159 | 1.0199 | 0.111* | |
C22 | 0.5561 (2) | 0.3282 (5) | 0.94892 (11) | 0.0443 (8) | |
O23 | 0.47744 (16) | −0.2188 (3) | 0.85283 (8) | 0.0406 (5) | |
H23A | 0.501 (2) | −0.301 (6) | 0.8730 (13) | 0.061* | |
H23B | 0.491 (2) | −0.261 (5) | 0.8317 (11) | 0.061* | |
N21 | 0.35402 (14) | 0.1320 (3) | 0.86523 (7) | 0.0266 (5) | |
N22 | 0.20452 (15) | 0.1181 (3) | 0.84211 (9) | 0.0313 (5) | |
H22 | 0.151 (2) | 0.117 (4) | 0.8255 (11) | 0.047* | |
C23 | 0.32837 (19) | 0.1359 (4) | 0.90557 (10) | 0.0306 (6) | |
H23 | 0.3687 | 0.1427 | 0.9378 | 0.037* | |
C24 | 0.23612 (19) | 0.1283 (4) | 0.89140 (10) | 0.0322 (6) | |
H24 | 0.2007 | 0.1299 | 0.9116 | 0.039* | |
C25 | 0.27660 (18) | 0.1209 (4) | 0.82773 (10) | 0.0302 (6) | |
H25 | 0.2730 | 0.1156 | 0.7952 | 0.036* | |
N23 | 0.59503 (14) | 0.1762 (3) | 0.84896 (8) | 0.0267 (5) | |
C26 | 0.68096 (18) | 0.1712 (4) | 0.88060 (10) | 0.0310 (6) | |
H26 | 0.6905 | 0.1466 | 0.9135 | 0.037* | |
C27 | 0.75568 (18) | 0.2008 (4) | 0.86681 (10) | 0.0335 (6) | |
H27 | 0.8152 | 0.1958 | 0.8898 | 0.040* | |
C28 | 0.74218 (18) | 0.2377 (4) | 0.81882 (10) | 0.0329 (6) | |
H28 | 0.7924 | 0.2594 | 0.8087 | 0.040* | |
C29 | 0.65364 (17) | 0.2426 (4) | 0.78565 (10) | 0.0304 (6) | |
H29 | 0.6427 | 0.2678 | 0.7527 | 0.036* | |
C30 | 0.58178 (17) | 0.2096 (4) | 0.80209 (9) | 0.0256 (6) | |
C31 | 0.48344 (17) | 0.2066 (4) | 0.76946 (9) | 0.0273 (6) | |
O24 | 0.42492 (12) | 0.1806 (3) | 0.78998 (6) | 0.0311 (4) | |
O25 | 0.46485 (12) | 0.2296 (3) | 0.72527 (6) | 0.0342 (5) | |
O6A | −0.1358 (10) | −0.1813 (8) | 0.5179 (2) | 0.093 (4) | 0.625 (18) |
O6B | −0.2045 (18) | −0.131 (3) | 0.5055 (6) | 0.102 (8) | 0.236 (18) |
O26A | 0.6386 (11) | −0.1825 (9) | 0.9762 (2) | 0.089 (4) | 0.64 (2) |
O26B | 0.703 (2) | −0.136 (4) | 0.9874 (7) | 0.085 (7) | 0.23 (2) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.02498 (19) | 0.0327 (2) | 0.01962 (18) | −0.00169 (13) | 0.00546 (14) | 0.00012 (13) |
O1 | 0.0376 (11) | 0.0452 (12) | 0.0221 (10) | −0.0082 (9) | 0.0052 (9) | 0.0013 (9) |
O2 | 0.0714 (16) | 0.0472 (14) | 0.0465 (13) | −0.0046 (12) | 0.0101 (12) | −0.0057 (12) |
C1 | 0.084 (3) | 0.077 (3) | 0.0309 (19) | −0.015 (2) | −0.0001 (19) | 0.0092 (18) |
C2 | 0.0341 (16) | 0.051 (2) | 0.0281 (16) | −0.0070 (14) | 0.0043 (13) | 0.0062 (14) |
O3 | 0.0428 (12) | 0.0351 (12) | 0.0320 (12) | −0.0045 (9) | 0.0158 (10) | −0.0006 (9) |
N1 | 0.0301 (12) | 0.0292 (12) | 0.0238 (12) | −0.0009 (9) | 0.0082 (10) | 0.0018 (9) |
N2 | 0.0240 (12) | 0.0363 (13) | 0.0378 (14) | −0.0009 (11) | 0.0088 (11) | 0.0038 (11) |
C3 | 0.0361 (16) | 0.0345 (16) | 0.0243 (14) | −0.0025 (12) | 0.0109 (12) | 0.0012 (11) |
C4 | 0.0371 (17) | 0.0360 (15) | 0.0351 (16) | −0.0025 (13) | 0.0175 (14) | 0.0013 (13) |
C5 | 0.0302 (15) | 0.0306 (14) | 0.0287 (15) | −0.0021 (12) | 0.0095 (12) | 0.0021 (12) |
N3 | 0.0277 (12) | 0.0278 (12) | 0.0246 (12) | 0.0013 (9) | 0.0057 (10) | 0.0008 (9) |
C6 | 0.0296 (15) | 0.0318 (15) | 0.0283 (15) | 0.0012 (12) | 0.0028 (12) | 0.0002 (12) |
C7 | 0.0248 (14) | 0.0298 (15) | 0.0411 (17) | 0.0017 (11) | 0.0042 (13) | −0.0029 (13) |
C8 | 0.0285 (15) | 0.0400 (17) | 0.0415 (17) | 0.0020 (12) | 0.0133 (13) | −0.0048 (13) |
C9 | 0.0303 (15) | 0.0401 (17) | 0.0288 (14) | 0.0030 (12) | 0.0128 (12) | −0.0052 (12) |
C10 | 0.0295 (14) | 0.0225 (13) | 0.0276 (14) | 0.0022 (11) | 0.0085 (12) | −0.0021 (11) |
C11 | 0.0273 (14) | 0.0257 (14) | 0.0266 (14) | 0.0017 (11) | 0.0082 (12) | −0.0036 (11) |
O4 | 0.0246 (10) | 0.0442 (11) | 0.0219 (9) | −0.0002 (8) | 0.0075 (8) | −0.0018 (8) |
O5 | 0.0310 (10) | 0.0481 (12) | 0.0202 (10) | 0.0012 (9) | 0.0081 (8) | −0.0032 (8) |
Cu2 | 0.02388 (19) | 0.0333 (2) | 0.01921 (18) | 0.00230 (13) | 0.00662 (14) | 0.00069 (13) |
O21 | 0.0347 (11) | 0.0484 (13) | 0.0213 (10) | 0.0060 (9) | 0.0076 (8) | 0.0001 (9) |
O22 | 0.123 (2) | 0.0447 (15) | 0.0449 (14) | 0.0208 (15) | 0.0223 (15) | 0.0053 (12) |
C21 | 0.092 (3) | 0.077 (3) | 0.0317 (19) | 0.017 (2) | −0.004 (2) | −0.0132 (18) |
C22 | 0.0447 (19) | 0.052 (2) | 0.0327 (17) | 0.0127 (15) | 0.0089 (15) | −0.0071 (15) |
O23 | 0.0564 (14) | 0.0368 (12) | 0.0364 (12) | 0.0089 (10) | 0.0261 (11) | 0.0012 (9) |
N21 | 0.0278 (12) | 0.0307 (12) | 0.0225 (11) | 0.0032 (9) | 0.0103 (10) | 0.0014 (9) |
N22 | 0.0225 (12) | 0.0345 (13) | 0.0359 (14) | 0.0004 (10) | 0.0087 (11) | 0.0013 (10) |
C23 | 0.0371 (16) | 0.0312 (15) | 0.0259 (14) | 0.0006 (12) | 0.0142 (12) | 0.0019 (11) |
C24 | 0.0368 (16) | 0.0320 (15) | 0.0333 (15) | 0.0012 (12) | 0.0191 (13) | 0.0034 (12) |
C25 | 0.0306 (15) | 0.0339 (15) | 0.0282 (14) | 0.0026 (12) | 0.0128 (12) | 0.0002 (12) |
N23 | 0.0262 (12) | 0.0298 (12) | 0.0233 (12) | 0.0008 (9) | 0.0075 (10) | −0.0008 (9) |
C26 | 0.0285 (15) | 0.0351 (16) | 0.0247 (14) | 0.0016 (11) | 0.0032 (12) | −0.0027 (11) |
C27 | 0.0254 (15) | 0.0325 (15) | 0.0390 (17) | −0.0004 (12) | 0.0065 (13) | −0.0051 (13) |
C28 | 0.0287 (15) | 0.0315 (16) | 0.0421 (17) | −0.0008 (12) | 0.0166 (13) | −0.0056 (13) |
C29 | 0.0305 (15) | 0.0315 (16) | 0.0307 (15) | −0.0024 (11) | 0.0125 (12) | −0.0034 (12) |
C30 | 0.0258 (14) | 0.0232 (13) | 0.0277 (14) | −0.0014 (11) | 0.0091 (11) | −0.0023 (11) |
C31 | 0.0284 (14) | 0.0250 (13) | 0.0281 (15) | −0.0009 (11) | 0.0095 (12) | 0.0005 (11) |
O24 | 0.0239 (10) | 0.0484 (12) | 0.0217 (10) | −0.0027 (8) | 0.0087 (8) | 0.0026 (8) |
O25 | 0.0302 (10) | 0.0526 (12) | 0.0203 (10) | −0.0045 (9) | 0.0095 (8) | 0.0034 (9) |
O6A | 0.151 (10) | 0.058 (3) | 0.052 (3) | −0.016 (4) | 0.012 (4) | −0.001 (2) |
O6B | 0.077 (15) | 0.172 (18) | 0.051 (9) | 0.008 (12) | 0.012 (9) | 0.008 (9) |
O26A | 0.130 (11) | 0.066 (3) | 0.053 (3) | 0.016 (4) | 0.008 (4) | 0.003 (2) |
O26B | 0.063 (15) | 0.130 (14) | 0.052 (9) | 0.015 (11) | 0.006 (9) | −0.001 (8) |
Cu1—O1 | 1.9381 (18) | Cu2—O21 | 1.9401 (18) |
Cu1—N1 | 1.954 (2) | Cu2—N21 | 1.961 (2) |
Cu1—O4 | 1.9897 (18) | Cu2—O24 | 1.9923 (17) |
Cu1—N3 | 2.000 (2) | Cu2—N23 | 2.007 (2) |
Cu1—O3 | 2.369 (2) | Cu2—O23 | 2.345 (2) |
O1—C2 | 1.272 (3) | O21—C22 | 1.265 (4) |
O2—C2 | 1.215 (4) | O22—C22 | 1.213 (4) |
C1—C2 | 1.517 (4) | C21—C22 | 1.528 (4) |
C1—H1A | 0.9700 | C21—H21A | 0.9700 |
C1—H1B | 0.9700 | C21—H21B | 0.9700 |
C1—H1C | 0.9700 | C21—H21C | 0.9700 |
O3—H3A | 0.80 (3) | O23—H23A | 0.79 (4) |
O3—H3B | 0.76 (3) | O23—H23B | 0.78 (3) |
N1—C5 | 1.327 (3) | N21—C25 | 1.324 (3) |
N1—C3 | 1.385 (3) | N21—C23 | 1.379 (3) |
N2—C5 | 1.335 (3) | N22—C25 | 1.330 (3) |
N2—C4 | 1.360 (3) | N22—C24 | 1.362 (3) |
N2—H2 | 0.81 (3) | N22—H22 | 0.81 (3) |
C3—C4 | 1.353 (4) | C23—C24 | 1.350 (4) |
C3—H3 | 0.9400 | C23—H23 | 0.9400 |
C4—H4 | 0.9400 | C24—H24 | 0.9400 |
C5—H5 | 0.9400 | C25—H25 | 0.9400 |
N3—C6 | 1.336 (3) | N23—C26 | 1.339 (3) |
N3—C10 | 1.346 (3) | N23—C30 | 1.340 (3) |
C6—C7 | 1.381 (4) | C26—C27 | 1.373 (4) |
C6—H6 | 0.9400 | C26—H26 | 0.9400 |
C7—C8 | 1.374 (4) | C27—C28 | 1.375 (4) |
C7—H7 | 0.9400 | C27—H27 | 0.9400 |
C8—C9 | 1.385 (4) | C28—C29 | 1.386 (4) |
C8—H8 | 0.9400 | C28—H28 | 0.9400 |
C9—C10 | 1.378 (4) | C29—C30 | 1.382 (3) |
C9—H9 | 0.9400 | C29—H29 | 0.9400 |
C10—C11 | 1.508 (3) | C30—C31 | 1.499 (3) |
C11—O5 | 1.238 (3) | C31—O25 | 1.240 (3) |
C11—O4 | 1.266 (3) | C31—O24 | 1.268 (3) |
O1—Cu1—N1 | 93.03 (8) | O21—Cu2—N21 | 93.27 (8) |
O1—Cu1—O4 | 175.09 (8) | O21—Cu2—O24 | 168.85 (8) |
N1—Cu1—O4 | 90.96 (8) | N21—Cu2—O24 | 90.81 (8) |
O1—Cu1—N3 | 93.73 (8) | O21—Cu2—N23 | 93.27 (8) |
N1—Cu1—N3 | 168.96 (9) | N21—Cu2—N23 | 170.93 (8) |
O4—Cu1—N3 | 81.90 (8) | O24—Cu2—N23 | 81.64 (8) |
O1—Cu1—O3 | 95.29 (8) | O21—Cu2—O23 | 97.94 (8) |
N1—Cu1—O3 | 94.94 (8) | N21—Cu2—O23 | 91.39 (8) |
O4—Cu1—O3 | 87.21 (7) | O24—Cu2—O23 | 92.33 (8) |
N3—Cu1—O3 | 93.12 (8) | N23—Cu2—O23 | 93.91 (8) |
C2—O1—Cu1 | 118.17 (18) | C22—O21—Cu2 | 115.70 (19) |
C2—C1—H1A | 109.5 | C22—C21—H21A | 109.5 |
C2—C1—H1B | 109.5 | C22—C21—H21B | 109.5 |
H1A—C1—H1B | 109.5 | H21A—C21—H21B | 109.5 |
C2—C1—H1C | 109.5 | C22—C21—H21C | 109.5 |
H1A—C1—H1C | 109.5 | H21A—C21—H21C | 109.5 |
H1B—C1—H1C | 109.5 | H21B—C21—H21C | 109.5 |
O2—C2—O1 | 124.1 (3) | O22—C22—O21 | 124.1 (3) |
O2—C2—C1 | 121.2 (3) | O22—C22—C21 | 121.0 (3) |
O1—C2—C1 | 114.8 (3) | O21—C22—C21 | 114.8 (3) |
Cu1—O3—H3A | 124 (3) | Cu2—O23—H23A | 128 (3) |
Cu1—O3—H3B | 115 (3) | Cu2—O23—H23B | 117 (3) |
H3A—O3—H3B | 102 (4) | H23A—O23—H23B | 100 (4) |
C5—N1—C3 | 105.2 (2) | C25—N21—C23 | 105.5 (2) |
C5—N1—Cu1 | 125.80 (18) | C25—N21—Cu2 | 125.37 (18) |
C3—N1—Cu1 | 128.53 (18) | C23—N21—Cu2 | 129.15 (19) |
C5—N2—C4 | 107.9 (2) | C25—N22—C24 | 107.8 (2) |
C5—N2—H2 | 128 (2) | C25—N22—H22 | 128 (2) |
C4—N2—H2 | 124 (2) | C24—N22—H22 | 124 (2) |
C4—C3—N1 | 109.3 (2) | C24—C23—N21 | 109.2 (2) |
C4—C3—H3 | 125.4 | C24—C23—H23 | 125.4 |
N1—C3—H3 | 125.4 | N21—C23—H23 | 125.4 |
C3—C4—N2 | 106.4 (2) | C23—C24—N22 | 106.4 (2) |
C3—C4—H4 | 126.8 | C23—C24—H24 | 126.8 |
N2—C4—H4 | 126.8 | N22—C24—H24 | 126.8 |
N1—C5—N2 | 111.1 (2) | N21—C25—N22 | 111.1 (2) |
N1—C5—H5 | 124.4 | N21—C25—H25 | 124.4 |
N2—C5—H5 | 124.4 | N22—C25—H25 | 124.4 |
C6—N3—C10 | 118.4 (2) | C26—N23—C30 | 118.6 (2) |
C6—N3—Cu1 | 128.90 (19) | C26—N23—Cu2 | 128.74 (19) |
C10—N3—Cu1 | 112.60 (17) | C30—N23—Cu2 | 112.62 (17) |
N3—C6—C7 | 122.3 (3) | N23—C26—C27 | 122.4 (3) |
N3—C6—H6 | 118.8 | N23—C26—H26 | 118.8 |
C7—C6—H6 | 118.8 | C27—C26—H26 | 118.8 |
C8—C7—C6 | 119.0 (3) | C26—C27—C28 | 119.1 (3) |
C8—C7—H7 | 120.5 | C26—C27—H27 | 120.5 |
C6—C7—H7 | 120.5 | C28—C27—H27 | 120.5 |
C7—C8—C9 | 119.2 (3) | C27—C28—C29 | 119.2 (3) |
C7—C8—H8 | 120.4 | C27—C28—H28 | 120.4 |
C9—C8—H8 | 120.4 | C29—C28—H28 | 120.4 |
C10—C9—C8 | 118.7 (3) | C30—C29—C28 | 118.6 (2) |
C10—C9—H9 | 120.7 | C30—C29—H29 | 120.7 |
C8—C9—H9 | 120.7 | C28—C29—H29 | 120.7 |
N3—C10—C9 | 122.3 (2) | N23—C30—C29 | 122.2 (2) |
N3—C10—C11 | 114.3 (2) | N23—C30—C31 | 114.5 (2) |
C9—C10—C11 | 123.3 (2) | C29—C30—C31 | 123.3 (2) |
O5—C11—O4 | 125.3 (2) | O25—C31—O24 | 124.9 (2) |
O5—C11—C10 | 118.9 (2) | O25—C31—C30 | 119.0 (2) |
O4—C11—C10 | 115.8 (2) | O24—C31—C30 | 116.1 (2) |
C11—O4—Cu1 | 115.26 (16) | C31—O24—Cu2 | 115.06 (16) |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3A···O2i | 0.80 (3) | 1.99 (3) | 2.790 (3) | 173 (4) |
O3—H3B···O5ii | 0.76 (3) | 2.08 (3) | 2.826 (3) | 168 (4) |
N2—H2···O25 | 0.81 (3) | 1.96 (3) | 2.758 (3) | 173 (3) |
O23—H23A···O22i | 0.79 (4) | 2.01 (4) | 2.792 (3) | 169 (4) |
O23—H23B···O25iii | 0.78 (3) | 2.02 (3) | 2.765 (3) | 161 (4) |
N22—H22···O5 | 0.81 (3) | 1.96 (3) | 2.767 (3) | 173 (3) |
Symmetry codes: (i) x, y−1, z; (ii) −x, y−1/2, −z+3/2; (iii) −x+1, y−1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | [Cu(C6H4NO2)(C2H3O2)(C3H4N2)(H2O)]·0.87H2O |
Mr | 346.44 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 203 |
a, b, c (Å) | 15.5708 (13), 6.5334 (5), 29.437 (2) |
β (°) | 110.333 (5) |
V (Å3) | 2808.0 (4) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 1.59 |
Crystal size (mm) | 0.21 × 0.15 × 0.04 |
Data collection | |
Diffractometer | Bruker APEXII CCD area-detector diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 1996) |
Tmin, Tmax | 0.731, 0.941 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 30383, 5430, 3948 |
Rint | 0.049 |
(sin θ/λ)max (Å−1) | 0.615 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.035, 0.096, 1.08 |
No. of reflections | 5430 |
No. of parameters | 421 |
No. of restraints | 2 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.36, −0.46 |
Computer programs: APEX2 (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2009), publCIF (Westrip, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3A···O2i | 0.80 (3) | 1.99 (3) | 2.790 (3) | 173 (4) |
O3—H3B···O5ii | 0.76 (3) | 2.08 (3) | 2.826 (3) | 168 (4) |
N2—H2···O25 | 0.81 (3) | 1.96 (3) | 2.758 (3) | 173 (3) |
O23—H23A···O22i | 0.79 (4) | 2.01 (4) | 2.792 (3) | 169 (4) |
O23—H23B···O25iii | 0.78 (3) | 2.02 (3) | 2.765 (3) | 161 (4) |
N22—H22···O5 | 0.81 (3) | 1.96 (3) | 2.767 (3) | 173 (3) |
Symmetry codes: (i) x, y−1, z; (ii) −x, y−1/2, −z+3/2; (iii) −x+1, y−1/2, −z+3/2. |
The asymmetric unit of the title complex, (I), has two identical chemical formula units (Z' = 2), i.e. two symmetry-independent molecules including the partially occupied and disordered solvent water (Fig. 1a). The two independent molecules have similar structural data, hence there is no immediately apparent significant conformational difference (Fig. 1b). The Cu atom is in a square-pyramidal environment with trans N and trans O donor atoms, respectively, and long apical Cu—OH2 bonds due to the Jahn–Teller effect.
Bond lengths and angles in (I) are as expected. The crystal packing is governed by O—H···O and N—H···O hydrogen bonding (Table 1, Fig. 2), the geometric parameters of which are within the normal range (Habib & Janiak, 2008; Wisser & Janiak, 2007a,b). Complementary N—H···O bonds are formed between the two symmetry-independent complex molecules from their imidazole N—H to the uncoordinated picolinate carboxylate O atom (Fig. 1a). The aqua ligand forms hydrogen bonds to both uncoordinated carboxylate O atoms of the picolinate and acetate ligands (Fig. 2). Together, these hydrogen bonds give a two-dimensional hydrogen-bonded double layer parallel to the ab plane (Fig. 2). Furthermore, the partially occupied solvent water atoms O6A and O26A form hydrogen bonds between acetate atoms O1 and O2, and O21 and O22, respectively, of two adjacent molecules along b (not shown, H atoms could not be found). π–π interactions between the picolinate and imidazole rings add to the supramolecular two-dimensional double layer parallel to the ab plane (Fig. 3). The π–π stacking interactions can be viewed as strong because of the rather short centroid-to-centroid contacts (3.582–3.764 Å), small slip angles (23–28°) and short interplanar separations (3.1–3.4 Å), which translate into a sizeable overlap of the nearly parallel aromatic planes (interplanar angle 4.83 or 9.78°) (Janiak, 2000).
There is ongoing discussion of the origin of crystal structures with multiple identical molecules, i.e. formula units in the structural asymmetric unit or so-called Z' > 1 structures (Gavezotti, 2008; van Eijck & Kroon, 2000). These can be regarded as a `fossil relic' of a more stable form (Steed, 2003), as strong and special supramolecular interactions between the symmetry-independent units (Althoff et al., 2006; Babu & Nangia, 2007; Hao et al., 2005) or as a crystal `on the way' (Desiraju, 2007; Nichol & Clegg, 2007; Ruiz et al., 2008). The impossibility of packing chiral molecules in a centrosymmetric structure can also lead to the presence of two independent molecules (Anderson & Steed, 2007). A Z' > 1 structure is also obtained when the molecule has different quasi-energetic conformations, with these conformations co-existing in the crystal structure (Hosseini Monfared et al., 2009; Roy et al., 2006).
Two X-ray data sets were collected on two crystals of the title compound from two different batches to ascertain the Z' = 2 phenomenon. One crystal was structurally investigated after drying and the other was taken directly from the mother liquor. Both data sets refined to the identical Z' = 2 structure, including the same disordered and partially occupied solvent water molecules. The complementary N—H···O hydrogen-bonding interaction between the molecules containing atoms Cu1 and Cu2 may be viewed as a special supramolecular interaction which creates a `dimer' and thereby gives a Z' = 2 structure. However, the two independent molecules are superficially related by a pseudo C2 axis at (1/2, y, 1/4) (Fig. 1a) or a pseudo n-glide plane at (0, 1/2, 0), thus leading to a possible refinement in C2/c (see Supplementary material, _refine_special_details section). The only atoms with no symmetry-related counterpart are C8, C9, C28 and C29 from the aromatic ring of the picolinate group (Fig. 1a). It is here where the two molecules deviate most in their overlay and where a tilt disorder occurs upon refinement in C2/c. Then the Z' = 2 structure would be due to quasi-energetic conformations co-existing in the crystal. However, we view both the `dimer' and the slight conformational difference, and hence the Z' = 2 structure of (I), as consequences of partial crystal water loss, which apparently takes place when the compound is still in its mother liquor, thereby representing a `crystal on the way' (Desiraju, 2007; Ruiz et al., 2008).