The title compound, poly[[[diaquacopper(II)]-di-μ-4,4′-bipyridyl] bis(3-carboxy-1-benzofuran-2-carboxylate) pentahydrate], {[Cu(C10H8N2)2(H2O)2](C10H5O5)2·5H2O}n, crystallizes in a single-framework architecture. It is composed of two-dimensional square-grid coordination networks of 1:2:2 copper–4,4′-bipyridine–water units, wherein each copper ion coordinates equatorially to four bipyridyl units and axially to two water ligands. The polymeric nets are intercalated by layers of the benzofurandicarboxylic acid monoanions and additional water species. An extensive array of hydrogen bonds interlinks the various components of the structure. The Cu atom and the bipyridyl entities are located on axes of twofold rotation. This study confirms the preferred monoanionic nature of the benzofurandicarboxylic acid molecule. It reveals a rarely observed extended coordination polymer composed only of copper ions and bipyridyl linkers, and an interesting hydrogen-bonding connectivity between the polymeric layers aided by the benzofurandicarboxylic acid and water components intercalated in the structure.
Supporting information
CCDC reference: 724182
Copper nitrate, benzofurandicarboxylic acid, 4,4'-bipyridine and all the other
solvents (see below) were obtained commercially. Cu(NO3)2.2.5H2O (0.058 g, 0.25 mmol) and 1-benzofuran-2,3-dicarboxylic acid (0.52 g, 0.25 mmol) were
added in a glass tube to 10 ml of a 1:1 mixture of
N,N'-dimethylformamide and water. A solution of 4,4'-bipyridine
(0.078 g, 0.5 mmol) in 4 ml of ethanol was then layered carefully on top of
the mixture. Green blocks of the title compound deposited after about one
week. IR (KBr, cm-1): 3447 (water stretching vibration); 1718 (COOH); 1630
and 1590 (COO- asymmetric stretching); 1402 and 1323 (COO- symmetric
stretching); 1224 (m); 1093 (m); 1018 (w); 869
(m); 831 (m); 745 (w); 635 (w). The asymmetric and
symmetric O—H stretching vibrations of the water of hydration appear as a
broad band centered at 3447 cm-1. The IR spectrum clearly indicates the
presence of both protonated carboxyl and deprotonated carboxylate groups, as
it is confirmed also by the crystallographic analyses. The series of medium or
weak intensity bands within 1224–645 cm-1 is associated with the
4,4'-bipyridyl and the benzofuran units.
H atoms bound to C atoms were located in calculated positions and were
constrained to ride on their parent atoms, with C—H distances of 0.95 Å
and with Uiso(H) set at 1.2Ueq(C). Most of the H atoms bound
to O could be located in difference Fourier maps. The remaining H atoms, which
could not be located reliably, were placed in calculated positions to optimize
intermolecular hydrogen bonding. The corresponding O—H distances were then
restrained to 0.85 Å, and assigned Uiso(H) values of
1.5Ueq(O) [1.2 according to CIF]. Their parameters were not
refined in the final least-squares calculations. The residual electron density
Fourier maps contained four peaks within 1–2 e A-3, reflecting possible
partial rotational disorder of the noncoordinated benzofurandicarboxylic acid
molecules. This disorder could not be reliably modeled by discrete atoms. Six
SIMU-type restraints were applied to the displacement parameters of atoms C39
and C40 atoms.
Data collection: COLLECT (Nonius, 1999); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).
poly[[[diaquacopper(II)]-di-µ-4,4'-bipyridyl]
bis(3-carboxy-1-benzofuran-2-carboxylate) pentahydrate]
top
Crystal data top
[Cu(C10H8N2)2(H2O)2](C10H5O5)2·5H2O | F(000) = 3784 |
Mr = 912.30 | Dx = 1.522 Mg m−3 |
Orthorhombic, Pccn | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ab 2ac | Cell parameters from 10233 reflections |
a = 15.8470 (2) Å | θ = 1.6–28.2° |
b = 22.2874 (3) Å | µ = 0.63 mm−1 |
c = 22.5446 (3) Å | T = 110 K |
V = 7962.49 (18) Å3 | Blocks, green |
Z = 8 | 0.40 × 0.40 × 0.30 mm |
Data collection top
Nonius KappaCCD diffractometer | 6077 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.057 |
Graphite monochromator | θmax = 28.2°, θmin = 1.6° |
Detector resolution: 12.8 pixels mm-1 | h = 0→20 |
0.7° ω scans | k = 0→29 |
58792 measured reflections | l = 0→29 |
9629 independent reflections | |
Refinement top
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)] = 0.065 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.210 | H-atom parameters constrained |
S = 1.09 | w = 1/[σ2(Fo2) + (0.1107P)2 + 9.1733P] where P = (Fo2 + 2Fc2)/3 |
9628 reflections | (Δ/σ)max = 0.001 |
564 parameters | Δρmax = 1.97 e Å−3 |
6 restraints | Δρmin = −0.88 e Å−3 |
Crystal data top
[Cu(C10H8N2)2(H2O)2](C10H5O5)2·5H2O | V = 7962.49 (18) Å3 |
Mr = 912.30 | Z = 8 |
Orthorhombic, Pccn | Mo Kα radiation |
a = 15.8470 (2) Å | µ = 0.63 mm−1 |
b = 22.2874 (3) Å | T = 110 K |
c = 22.5446 (3) Å | 0.40 × 0.40 × 0.30 mm |
Data collection top
Nonius KappaCCD diffractometer | 6077 reflections with I > 2σ(I) |
58792 measured reflections | Rint = 0.057 |
9629 independent reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.065 | 6 restraints |
wR(F2) = 0.210 | H-atom parameters constrained |
S = 1.09 | Δρmax = 1.97 e Å−3 |
9628 reflections | Δρmin = −0.88 e Å−3 |
564 parameters | |
Special details top
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 residual electron density Fourier maps contained four peaks within 1–2 e/A**3, reflecting on partial rotational disorder of the benzofuran
dicarboxylic acid moieties. This disorder could not be reliably modeled by
discrete atoms. Yet all the H-atoms bound to oxygen could be located on these
maps. |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
Cu1 | 0.2500 | 0.2500 | 0.28210 (2) | 0.01412 (15) | |
Cu2 | 0.2500 | −0.2500 | 0.28688 (2) | 0.01468 (15) | |
O3 | 0.10168 (15) | 0.24724 (10) | 0.28069 (9) | 0.0210 (5) | |
H3A | 0.0776 | 0.2759 | 0.2625 | 0.025* | |
H3B | 0.0698 | 0.2479 | 0.3110 | 0.025* | |
O4 | 0.39958 (16) | −0.24054 (10) | 0.28730 (9) | 0.0220 (5) | |
H4A | 0.4272 | −0.2095 | 0.2771 | 0.026* | |
H4B | 0.4394 | −0.2658 | 0.2834 | 0.026* | |
N5 | 0.24911 (16) | 0.15919 (12) | 0.28191 (10) | 0.0146 (5) | |
C6 | 0.3048 (2) | 0.12751 (14) | 0.31400 (13) | 0.0182 (6) | |
H6 | 0.3468 | 0.1486 | 0.3357 | 0.022* | |
C7 | 0.3037 (2) | 0.06557 (14) | 0.31684 (14) | 0.0210 (7) | |
H7 | 0.3437 | 0.0449 | 0.3407 | 0.025* | |
C8 | 0.2439 (2) | 0.03357 (15) | 0.28474 (12) | 0.0171 (7) | |
C9 | 0.1860 (2) | 0.06665 (14) | 0.25098 (14) | 0.0188 (6) | |
H9 | 0.1439 | 0.0466 | 0.2285 | 0.023* | |
C10 | 0.1904 (2) | 0.12850 (14) | 0.25066 (13) | 0.0186 (6) | |
H10 | 0.1508 | 0.1504 | 0.2276 | 0.022* | |
C11 | 0.2418 (2) | −0.03304 (15) | 0.28617 (13) | 0.0180 (7) | |
C12 | 0.2880 (2) | −0.06514 (15) | 0.32810 (13) | 0.0217 (7) | |
H12 | 0.3203 | −0.0445 | 0.3571 | 0.026* | |
C13 | 0.2865 (2) | −0.12704 (15) | 0.32729 (13) | 0.0215 (7) | |
H13 | 0.3183 | −0.1480 | 0.3564 | 0.026* | |
N14 | 0.24241 (17) | −0.15910 (12) | 0.28760 (10) | 0.0162 (6) | |
C15 | 0.1956 (2) | −0.12850 (14) | 0.24770 (14) | 0.0200 (7) | |
H15 | 0.1624 | −0.1503 | 0.2200 | 0.024* | |
C16 | 0.1943 (2) | −0.06652 (14) | 0.24579 (14) | 0.0209 (7) | |
H16 | 0.1609 | −0.0466 | 0.2169 | 0.025* | |
N17 | 0.2500 | 0.2500 | 0.37392 (15) | 0.0144 (7) | |
C18 | 0.3022 (2) | 0.28581 (14) | 0.40458 (13) | 0.0188 (6) | |
H18 | 0.3391 | 0.3116 | 0.3833 | 0.023* | |
C19 | 0.3045 (2) | 0.28667 (15) | 0.46607 (13) | 0.0200 (7) | |
H19 | 0.3431 | 0.3123 | 0.4860 | 0.024* | |
C20 | 0.2500 | 0.2500 | 0.49897 (19) | 0.0169 (9) | |
C21 | 0.2500 | 0.2500 | 0.56467 (18) | 0.0162 (9) | |
C22 | 0.1940 (2) | 0.21464 (15) | 0.59750 (13) | 0.0217 (7) | |
H22 | 0.1542 | 0.1899 | 0.5776 | 0.026* | |
C23 | 0.1963 (2) | 0.21569 (15) | 0.65863 (13) | 0.0208 (7) | |
H23 | 0.1580 | 0.1909 | 0.6798 | 0.025* | |
N24 | 0.2500 | 0.2500 | 0.68975 (15) | 0.0149 (7) | |
N25 | 0.2500 | −0.2500 | 0.37976 (15) | 0.0151 (7) | |
C26 | 0.3211 (2) | −0.26045 (15) | 0.41059 (14) | 0.0219 (7) | |
H26 | 0.3716 | −0.2686 | 0.3894 | 0.026* | |
C27 | 0.3237 (2) | −0.25988 (16) | 0.47196 (14) | 0.0226 (7) | |
H27 | 0.3757 | −0.2662 | 0.4920 | 0.027* | |
C28 | 0.2500 | −0.2500 | 0.50438 (19) | 0.0199 (9) | |
C29 | 0.2500 | −0.2500 | 0.57011 (19) | 0.0190 (9) | |
C30 | 0.1972 (2) | −0.21243 (15) | 0.60245 (14) | 0.0235 (7) | |
H30 | 0.1601 | −0.1858 | 0.5824 | 0.028* | |
C31 | 0.1986 (2) | −0.21377 (14) | 0.66382 (13) | 0.0201 (7) | |
H31 | 0.1617 | −0.1880 | 0.6850 | 0.024* | |
N32 | 0.2500 | −0.2500 | 0.69449 (15) | 0.0154 (7) | |
O33 | 0.6244 (2) | −0.00834 (13) | 0.05001 (13) | 0.0412 (7) | |
C34 | 0.6442 (3) | −0.00789 (19) | −0.00754 (18) | 0.0374 (10) | |
C35 | 0.6951 (3) | −0.0555 (2) | −0.03513 (18) | 0.0437 (11) | |
H35 | 0.7178 | −0.0884 | −0.0136 | 0.052* | |
C36 | 0.7065 (3) | −0.04779 (18) | −0.09484 (18) | 0.0377 (10) | |
H36 | 0.7390 | −0.0764 | −0.1161 | 0.045* | |
C37 | 0.6713 (3) | 0.00168 (18) | −0.1259 (2) | 0.0428 (11) | |
H37 | 0.6809 | 0.0044 | −0.1675 | 0.051* | |
C38 | 0.6246 (3) | 0.0456 (2) | −0.09936 (18) | 0.0420 (10) | |
H38 | 0.6015 | 0.0784 | −0.1208 | 0.050* | |
C39 | 0.6134 (3) | 0.03897 (18) | −0.03999 (16) | 0.0336 (9) | |
C40 | 0.5667 (2) | 0.07630 (18) | 0.00688 (15) | 0.0311 (8) | |
C41 | 0.5791 (2) | 0.04337 (16) | 0.05673 (18) | 0.0323 (8) | |
C42 | 0.5504 (3) | 0.05025 (17) | 0.11891 (17) | 0.0338 (9) | |
O43 | 0.5128 (2) | 0.09921 (13) | 0.13157 (11) | 0.0403 (7) | |
O44 | 0.5630 (2) | 0.01036 (13) | 0.15628 (14) | 0.0454 (8) | |
C45 | 0.5226 (3) | 0.1338 (2) | −0.00085 (16) | 0.0364 (9) | |
O46 | 0.48989 (17) | 0.16044 (12) | 0.04495 (12) | 0.0368 (6) | |
H46 | 0.4944 | 0.1404 | 0.0769 | 0.044* | |
O47 | 0.51959 (19) | 0.15608 (14) | −0.05116 (12) | 0.0459 (8) | |
O48 | 0.53586 (18) | −0.02176 (12) | 0.36940 (12) | 0.0348 (6) | |
C49 | 0.5443 (3) | −0.07392 (18) | 0.40122 (18) | 0.0370 (9) | |
C50 | 0.5236 (3) | −0.13147 (19) | 0.38097 (19) | 0.0416 (10) | |
H50 | 0.5035 | −0.1385 | 0.3419 | 0.050* | |
C51 | 0.5341 (3) | −0.1768 (2) | 0.4209 (2) | 0.0478 (11) | |
H51 | 0.5220 | −0.2169 | 0.4094 | 0.057* | |
C52 | 0.5621 (3) | −0.1653 (2) | 0.4778 (2) | 0.0460 (11) | |
H52 | 0.5646 | −0.1978 | 0.5050 | 0.055* | |
C53 | 0.5863 (3) | −0.1099 (2) | 0.49744 (19) | 0.0458 (11) | |
H53 | 0.6089 | −0.1043 | 0.5361 | 0.055* | |
C54 | 0.5762 (3) | −0.0602 (2) | 0.45683 (17) | 0.0380 (10) | |
C55 | 0.5901 (3) | 0.00320 (19) | 0.45853 (17) | 0.0369 (10) | |
C56 | 0.5640 (2) | 0.02506 (18) | 0.40492 (15) | 0.0305 (8) | |
C57 | 0.5539 (2) | 0.08552 (17) | 0.37688 (15) | 0.0284 (8) | |
O58 | 0.51315 (17) | 0.08710 (11) | 0.32929 (10) | 0.0306 (6) | |
O59 | 0.58640 (19) | 0.12943 (13) | 0.40290 (14) | 0.0446 (7) | |
C60 | 0.6239 (3) | 0.0341 (2) | 0.51031 (19) | 0.0465 (11) | |
O61 | 0.6419 (2) | 0.09266 (16) | 0.50486 (14) | 0.0590 (9) | |
H61 | 0.6236 | 0.1045 | 0.4713 | 0.071* | |
O62 | 0.6374 (3) | 0.00702 (15) | 0.55580 (14) | 0.0575 (10) | |
O63 | 0.49322 (15) | 0.16130 (10) | 0.23558 (10) | 0.0254 (5) | |
H63A | 0.5003 | 0.1389 | 0.2055 | 0.030* | |
H63B | 0.4964 | 0.1359 | 0.2636 | 0.030* | |
O64 | 0.45224 (18) | −0.13367 (12) | 0.23727 (12) | 0.0377 (7) | |
H64A | 0.4894 | −0.1305 | 0.2103 | 0.045* | |
H64B | 0.4491 | −0.0973 | 0.2485 | 0.045* | |
O65 | 0.56775 (18) | −0.11523 (13) | 0.14635 (12) | 0.0384 (7) | |
H65A | 0.5406 | −0.1255 | 0.1155 | 0.046* | |
H65B | 0.5764 | −0.0780 | 0.1521 | 0.046* | |
O66 | 0.4520 (2) | −0.00921 (12) | 0.25046 (13) | 0.0435 (8) | |
H66A | 0.4906 | −0.0028 | 0.2250 | 0.052* | |
H66B | 0.4728 | 0.0103 | 0.2794 | 0.052* | |
O67 | 0.48782 (18) | 0.23463 (13) | 0.38303 (12) | 0.0413 (7) | |
H67A | 0.5188 | 0.2041 | 0.3888 | 0.050* | |
H67B | 0.5004 | 0.2631 | 0.4065 | 0.050* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
Cu1 | 0.0225 (3) | 0.0107 (3) | 0.0091 (3) | 0.0004 (2) | 0.000 | 0.000 |
Cu2 | 0.0238 (3) | 0.0108 (3) | 0.0095 (3) | 0.0000 (2) | 0.000 | 0.000 |
O3 | 0.0216 (12) | 0.0199 (12) | 0.0214 (11) | 0.0043 (9) | −0.0013 (9) | 0.0027 (9) |
O4 | 0.0231 (13) | 0.0199 (12) | 0.0230 (12) | −0.0005 (10) | 0.0025 (9) | 0.0023 (9) |
N5 | 0.0200 (14) | 0.0108 (12) | 0.0130 (12) | 0.0004 (10) | 0.0008 (10) | −0.0014 (9) |
C6 | 0.0222 (16) | 0.0149 (15) | 0.0176 (14) | 0.0009 (13) | −0.0040 (12) | 0.0009 (12) |
C7 | 0.0252 (18) | 0.0160 (16) | 0.0217 (15) | 0.0029 (13) | −0.0034 (13) | 0.0012 (12) |
C8 | 0.0219 (17) | 0.0144 (15) | 0.0148 (14) | −0.0007 (12) | −0.0002 (12) | 0.0001 (11) |
C9 | 0.0217 (17) | 0.0163 (15) | 0.0185 (14) | −0.0009 (13) | −0.0032 (12) | −0.0017 (12) |
C10 | 0.0227 (17) | 0.0181 (15) | 0.0150 (13) | −0.0008 (13) | −0.0043 (12) | 0.0008 (12) |
C11 | 0.0225 (17) | 0.0134 (15) | 0.0182 (15) | 0.0000 (12) | 0.0010 (12) | −0.0007 (12) |
C12 | 0.0308 (19) | 0.0188 (16) | 0.0155 (14) | −0.0021 (14) | −0.0066 (13) | −0.0017 (12) |
C13 | 0.0318 (19) | 0.0151 (15) | 0.0178 (15) | −0.0015 (14) | −0.0055 (13) | 0.0018 (12) |
N14 | 0.0227 (15) | 0.0128 (13) | 0.0131 (12) | 0.0008 (10) | −0.0013 (10) | −0.0008 (10) |
C15 | 0.0256 (17) | 0.0158 (15) | 0.0187 (14) | −0.0016 (13) | −0.0039 (13) | −0.0014 (12) |
C16 | 0.0259 (18) | 0.0177 (16) | 0.0190 (14) | 0.0012 (14) | −0.0059 (13) | 0.0019 (12) |
N17 | 0.0192 (19) | 0.0152 (18) | 0.0088 (15) | 0.0023 (15) | 0.000 | 0.000 |
C18 | 0.0234 (17) | 0.0163 (15) | 0.0166 (14) | −0.0021 (13) | 0.0001 (12) | −0.0007 (12) |
C19 | 0.0253 (17) | 0.0191 (16) | 0.0156 (14) | −0.0042 (14) | 0.0004 (12) | −0.0011 (12) |
C20 | 0.019 (2) | 0.017 (2) | 0.0140 (19) | 0.0004 (18) | 0.000 | 0.000 |
C21 | 0.021 (2) | 0.016 (2) | 0.0118 (19) | −0.0007 (17) | 0.000 | 0.000 |
C22 | 0.0242 (17) | 0.0248 (17) | 0.0161 (14) | −0.0031 (14) | −0.0018 (12) | −0.0009 (13) |
C23 | 0.0275 (18) | 0.0199 (16) | 0.0150 (14) | −0.0061 (14) | 0.0026 (13) | −0.0003 (12) |
N24 | 0.023 (2) | 0.0125 (17) | 0.0088 (16) | 0.0013 (15) | 0.000 | 0.000 |
N25 | 0.023 (2) | 0.0121 (17) | 0.0101 (16) | −0.0002 (15) | 0.000 | 0.000 |
C26 | 0.0247 (18) | 0.0254 (18) | 0.0155 (14) | 0.0053 (14) | 0.0003 (13) | 0.0021 (13) |
C27 | 0.0249 (19) | 0.0267 (18) | 0.0161 (14) | 0.0048 (14) | −0.0014 (13) | 0.0010 (13) |
C28 | 0.028 (3) | 0.018 (2) | 0.014 (2) | 0.0025 (19) | 0.000 | 0.000 |
C29 | 0.022 (2) | 0.021 (2) | 0.014 (2) | 0.0015 (18) | 0.000 | 0.000 |
C30 | 0.0303 (19) | 0.0243 (17) | 0.0158 (15) | 0.0055 (15) | −0.0024 (13) | −0.0001 (13) |
C31 | 0.0278 (18) | 0.0184 (15) | 0.0141 (14) | 0.0034 (14) | 0.0010 (12) | −0.0011 (12) |
N32 | 0.026 (2) | 0.0144 (18) | 0.0058 (15) | 0.0016 (15) | 0.000 | 0.000 |
O33 | 0.0488 (19) | 0.0387 (17) | 0.0360 (15) | 0.0044 (13) | 0.0049 (14) | 0.0020 (12) |
C34 | 0.036 (2) | 0.041 (2) | 0.035 (2) | −0.0102 (18) | −0.0057 (17) | 0.0123 (17) |
C35 | 0.048 (3) | 0.046 (3) | 0.038 (2) | −0.011 (2) | 0.0107 (19) | −0.0095 (19) |
C36 | 0.040 (2) | 0.031 (2) | 0.042 (2) | −0.0007 (18) | 0.0161 (19) | −0.0103 (17) |
C37 | 0.040 (3) | 0.038 (2) | 0.051 (3) | −0.0025 (19) | 0.002 (2) | −0.0088 (19) |
C38 | 0.044 (3) | 0.046 (3) | 0.036 (2) | −0.006 (2) | 0.0003 (19) | 0.0025 (19) |
C39 | 0.034 (2) | 0.034 (2) | 0.033 (2) | −0.0141 (17) | −0.0059 (16) | 0.0054 (16) |
C40 | 0.0258 (19) | 0.041 (2) | 0.0264 (17) | −0.0099 (16) | 0.0064 (15) | −0.0065 (16) |
C41 | 0.027 (2) | 0.0227 (18) | 0.047 (2) | 0.0017 (15) | −0.0045 (17) | −0.0077 (16) |
C42 | 0.039 (2) | 0.028 (2) | 0.0335 (19) | −0.0073 (17) | −0.0125 (17) | 0.0049 (17) |
O43 | 0.062 (2) | 0.0337 (16) | 0.0247 (13) | 0.0007 (14) | 0.0071 (13) | −0.0017 (11) |
O44 | 0.0481 (19) | 0.0383 (17) | 0.0498 (18) | −0.0070 (14) | −0.0124 (15) | 0.0132 (14) |
C45 | 0.033 (2) | 0.046 (2) | 0.0301 (19) | −0.0168 (19) | −0.0031 (17) | 0.0107 (17) |
O46 | 0.0366 (16) | 0.0272 (14) | 0.0466 (16) | 0.0048 (12) | 0.0008 (13) | 0.0090 (12) |
O47 | 0.0457 (18) | 0.0523 (19) | 0.0397 (15) | −0.0180 (15) | −0.0104 (14) | 0.0189 (14) |
O48 | 0.0400 (16) | 0.0300 (14) | 0.0345 (14) | −0.0005 (12) | −0.0098 (12) | 0.0052 (12) |
C49 | 0.039 (2) | 0.033 (2) | 0.038 (2) | 0.0077 (18) | 0.0001 (18) | 0.0085 (17) |
C50 | 0.045 (3) | 0.036 (2) | 0.044 (2) | 0.0030 (19) | −0.0034 (19) | −0.0016 (19) |
C51 | 0.048 (3) | 0.039 (2) | 0.057 (3) | 0.003 (2) | 0.001 (2) | 0.000 (2) |
C52 | 0.055 (3) | 0.039 (2) | 0.045 (2) | 0.007 (2) | 0.009 (2) | 0.011 (2) |
C53 | 0.044 (3) | 0.056 (3) | 0.037 (2) | 0.017 (2) | 0.0017 (19) | 0.000 (2) |
C54 | 0.038 (2) | 0.044 (2) | 0.0316 (19) | 0.0126 (19) | 0.0083 (17) | 0.0037 (18) |
C55 | 0.033 (2) | 0.052 (3) | 0.0254 (19) | 0.0175 (19) | −0.0008 (16) | −0.0053 (16) |
C56 | 0.027 (2) | 0.039 (2) | 0.0246 (17) | 0.0064 (17) | 0.0026 (15) | −0.0016 (16) |
C57 | 0.0273 (19) | 0.030 (2) | 0.0278 (17) | 0.0055 (16) | 0.0065 (15) | −0.0022 (15) |
O58 | 0.0371 (15) | 0.0312 (14) | 0.0236 (12) | 0.0027 (12) | −0.0005 (11) | 0.0035 (10) |
O59 | 0.0416 (17) | 0.0324 (16) | 0.0599 (19) | 0.0051 (13) | −0.0115 (15) | −0.0157 (14) |
C60 | 0.050 (3) | 0.049 (3) | 0.040 (2) | 0.015 (2) | −0.013 (2) | −0.017 (2) |
O61 | 0.071 (2) | 0.057 (2) | 0.0492 (19) | 0.0049 (18) | −0.0283 (17) | −0.0131 (16) |
O62 | 0.082 (3) | 0.059 (2) | 0.0317 (16) | 0.0191 (18) | −0.0242 (17) | −0.0083 (14) |
O63 | 0.0341 (14) | 0.0185 (12) | 0.0235 (11) | 0.0041 (10) | 0.0039 (10) | −0.0010 (10) |
O64 | 0.0489 (18) | 0.0248 (14) | 0.0393 (15) | −0.0055 (13) | 0.0109 (13) | −0.0011 (11) |
O65 | 0.0466 (17) | 0.0357 (15) | 0.0329 (14) | 0.0084 (13) | −0.0015 (12) | −0.0015 (12) |
O66 | 0.060 (2) | 0.0331 (16) | 0.0371 (15) | −0.0087 (14) | −0.0022 (14) | −0.0041 (12) |
O67 | 0.0501 (18) | 0.0378 (16) | 0.0361 (15) | 0.0114 (14) | −0.0174 (13) | −0.0083 (12) |
Geometric parameters (Å, º) top
Cu1—N5i | 2.024 (3) | C29—C30iii | 1.390 (4) |
Cu1—N5 | 2.024 (3) | C29—C30 | 1.390 (4) |
Cu1—N17 | 2.070 (3) | C30—C31 | 1.384 (4) |
Cu1—N24ii | 2.082 (3) | C30—H30 | 0.9500 |
Cu1—O3i | 2.351 (2) | C31—N32 | 1.339 (4) |
Cu1—O3 | 2.351 (2) | C31—H31 | 0.9500 |
Cu2—N14iii | 2.030 (3) | N32—C31iii | 1.339 (4) |
Cu2—N14 | 2.030 (3) | N32—Cu2iv | 2.083 (3) |
Cu2—N32ii | 2.083 (3) | O33—C34 | 1.335 (5) |
Cu2—N25 | 2.094 (3) | O33—C41 | 1.367 (5) |
Cu2—O4iii | 2.380 (2) | C34—C39 | 1.365 (6) |
Cu2—O4 | 2.380 (2) | C34—C35 | 1.471 (6) |
O3—H3A | 0.8500 | C35—C36 | 1.369 (6) |
O3—H3B | 0.8500 | C35—H35 | 0.9500 |
O4—H4A | 0.8499 | C36—C37 | 1.420 (6) |
O4—H4B | 0.8500 | C36—H36 | 0.9500 |
N5—C6 | 1.342 (4) | C37—C38 | 1.367 (6) |
N5—C10 | 1.352 (4) | C37—H37 | 0.9500 |
C6—C7 | 1.382 (4) | C38—C39 | 1.358 (5) |
C6—H6 | 0.9500 | C38—H38 | 0.9500 |
C7—C8 | 1.389 (4) | C39—C40 | 1.535 (5) |
C7—H7 | 0.9500 | C40—C41 | 1.356 (6) |
C8—C9 | 1.403 (4) | C40—C45 | 1.470 (6) |
C8—C11 | 1.485 (5) | C41—C42 | 1.481 (6) |
C9—C10 | 1.380 (4) | C42—O44 | 1.241 (5) |
C9—H9 | 0.9500 | C42—O43 | 1.276 (5) |
C10—H10 | 0.9500 | C45—O47 | 1.239 (4) |
C11—C12 | 1.393 (4) | C45—O46 | 1.299 (5) |
C11—C16 | 1.398 (4) | O46—H46 | 0.8500 |
C12—C13 | 1.380 (5) | O48—C49 | 1.372 (5) |
C12—H12 | 0.9500 | O48—C56 | 1.389 (5) |
C13—N14 | 1.341 (4) | C49—C54 | 1.386 (6) |
C13—H13 | 0.9500 | C49—C50 | 1.400 (6) |
N14—C15 | 1.351 (4) | C50—C51 | 1.363 (6) |
C15—C16 | 1.382 (4) | C50—H50 | 0.9500 |
C15—H15 | 0.9500 | C51—C52 | 1.383 (6) |
C16—H16 | 0.9500 | C51—H51 | 0.9500 |
N17—C18 | 1.341 (4) | C52—C53 | 1.366 (7) |
N17—C18i | 1.341 (4) | C52—H52 | 0.9500 |
C18—C19 | 1.387 (4) | C53—C54 | 1.446 (6) |
C18—H18 | 0.9500 | C53—H53 | 0.9500 |
C19—C20 | 1.401 (4) | C54—C55 | 1.431 (6) |
C19—H19 | 0.9500 | C55—C56 | 1.367 (5) |
C20—C19i | 1.401 (4) | C55—C60 | 1.458 (6) |
C20—C21 | 1.481 (6) | C56—C57 | 1.497 (5) |
C21—C22 | 1.399 (4) | C57—O58 | 1.252 (4) |
C21—C22i | 1.399 (4) | C57—O59 | 1.252 (5) |
C22—C23 | 1.379 (4) | C60—O62 | 1.209 (6) |
C22—H22 | 0.9500 | C60—O61 | 1.342 (6) |
C23—N24 | 1.342 (4) | O61—H61 | 0.8535 |
C23—H23 | 0.9500 | O63—H63A | 0.8500 |
N24—C23i | 1.342 (4) | O63—H63B | 0.8500 |
N24—Cu1iv | 2.082 (3) | O64—H64A | 0.8500 |
N25—C26iii | 1.344 (4) | O64—H64B | 0.8500 |
N25—C26 | 1.344 (4) | O65—H65A | 0.8501 |
C26—C27 | 1.384 (4) | O65—H65B | 0.8501 |
C26—H26 | 0.9500 | O66—H66A | 0.8500 |
C27—C28 | 1.396 (4) | O66—H66B | 0.8500 |
C27—H27 | 0.9500 | O67—H67A | 0.8500 |
C28—C27iii | 1.396 (4) | O67—H67B | 0.8499 |
C28—C29 | 1.482 (6) | | |
| | | |
N5i—Cu1—N5 | 179.76 (13) | C23i—N24—Cu1iv | 121.53 (18) |
N5i—Cu1—N17 | 90.12 (7) | C26iii—N25—C26 | 117.7 (4) |
N5—Cu1—N17 | 90.12 (7) | C26iii—N25—Cu2 | 121.14 (19) |
N5i—Cu1—N24ii | 89.88 (7) | C26—N25—Cu2 | 121.14 (19) |
N5—Cu1—N24ii | 89.88 (7) | N25—C26—C27 | 122.7 (3) |
N17—Cu1—N24ii | 180.0 | N25—C26—H26 | 118.6 |
N5i—Cu1—O3i | 88.10 (9) | C27—C26—H26 | 118.6 |
N5—Cu1—O3i | 91.90 (9) | C26—C27—C28 | 120.0 (3) |
N17—Cu1—O3i | 90.77 (5) | C26—C27—H27 | 120.0 |
N24ii—Cu1—O3i | 89.23 (5) | C28—C27—H27 | 120.0 |
N5i—Cu1—O3 | 91.90 (9) | C27—C28—C27iii | 116.8 (4) |
N5—Cu1—O3 | 88.10 (9) | C27—C28—C29 | 121.6 (2) |
N17—Cu1—O3 | 90.77 (5) | C27iii—C28—C29 | 121.6 (2) |
N24ii—Cu1—O3 | 89.23 (5) | C30iii—C29—C30 | 116.7 (4) |
O3i—Cu1—O3 | 178.46 (11) | C30iii—C29—C28 | 121.6 (2) |
N14iii—Cu2—N14 | 179.08 (13) | C30—C29—C28 | 121.6 (2) |
N14iii—Cu2—N32ii | 90.46 (7) | C31—C30—C29 | 120.1 (3) |
N14—Cu2—N32ii | 90.46 (7) | C31—C30—H30 | 120.0 |
N14iii—Cu2—N25 | 89.54 (7) | C29—C30—H30 | 120.0 |
N14—Cu2—N25 | 89.54 (7) | N32—C31—C30 | 122.6 (3) |
N32ii—Cu2—N25 | 180.0 | N32—C31—H31 | 118.7 |
N14iii—Cu2—O4iii | 88.31 (9) | C30—C31—H31 | 118.7 |
N14—Cu2—O4iii | 91.68 (9) | C31—N32—C31iii | 117.8 (4) |
N32ii—Cu2—O4iii | 90.23 (5) | C31—N32—Cu2iv | 121.09 (18) |
N25—Cu2—O4iii | 89.77 (5) | C31iii—N32—Cu2iv | 121.09 (18) |
N14iii—Cu2—O4 | 91.68 (9) | C34—O33—C41 | 103.0 (3) |
N14—Cu2—O4 | 88.32 (9) | O33—C34—C39 | 116.3 (4) |
N32ii—Cu2—O4 | 90.23 (5) | O33—C34—C35 | 122.3 (4) |
N25—Cu2—O4 | 89.77 (5) | C39—C34—C35 | 121.4 (4) |
O4iii—Cu2—O4 | 179.54 (10) | C36—C35—C34 | 113.4 (4) |
Cu1—O3—H3A | 115.9 | C36—C35—H35 | 123.3 |
Cu1—O3—H3B | 125.6 | C34—C35—H35 | 123.3 |
H3A—O3—H3B | 96.2 | C35—C36—C37 | 122.1 (4) |
Cu2—O4—H4A | 125.8 | C35—C36—H36 | 119.0 |
Cu2—O4—H4B | 132.8 | C37—C36—H36 | 119.0 |
H4A—O4—H4B | 97.4 | C38—C37—C36 | 123.5 (4) |
C6—N5—C10 | 117.9 (3) | C38—C37—H37 | 118.2 |
C6—N5—Cu1 | 121.3 (2) | C36—C37—H37 | 118.2 |
C10—N5—Cu1 | 120.8 (2) | C39—C38—C37 | 115.1 (4) |
N5—C6—C7 | 122.8 (3) | C39—C38—H38 | 122.4 |
N5—C6—H6 | 118.6 | C37—C38—H38 | 122.4 |
C7—C6—H6 | 118.6 | C38—C39—C34 | 124.4 (4) |
C6—C7—C8 | 119.9 (3) | C38—C39—C40 | 133.0 (4) |
C6—C7—H7 | 120.1 | C34—C39—C40 | 102.6 (3) |
C8—C7—H7 | 120.1 | C41—C40—C45 | 129.7 (3) |
C7—C8—C9 | 117.3 (3) | C41—C40—C39 | 102.0 (3) |
C7—C8—C11 | 121.2 (3) | C45—C40—C39 | 128.3 (3) |
C9—C8—C11 | 121.5 (3) | C40—C41—O33 | 116.1 (4) |
C10—C9—C8 | 119.6 (3) | C40—C41—C42 | 133.2 (4) |
C10—C9—H9 | 120.2 | O33—C41—C42 | 110.7 (3) |
C8—C9—H9 | 120.2 | O44—C42—O43 | 122.4 (4) |
N5—C10—C9 | 122.5 (3) | O44—C42—C41 | 121.3 (4) |
N5—C10—H10 | 118.7 | O43—C42—C41 | 116.3 (3) |
C9—C10—H10 | 118.7 | O47—C45—O46 | 121.9 (4) |
C12—C11—C16 | 116.8 (3) | O47—C45—C40 | 118.4 (4) |
C12—C11—C8 | 121.1 (3) | O46—C45—C40 | 119.6 (3) |
C16—C11—C8 | 122.1 (3) | C45—O46—H46 | 113.5 |
C13—C12—C11 | 119.7 (3) | C49—O48—C56 | 107.7 (3) |
C13—C12—H12 | 120.1 | O48—C49—C54 | 108.8 (4) |
C11—C12—H12 | 120.1 | O48—C49—C50 | 125.6 (4) |
N14—C13—C12 | 123.4 (3) | C54—C49—C50 | 125.6 (4) |
N14—C13—H13 | 118.3 | C51—C50—C49 | 115.8 (4) |
C12—C13—H13 | 118.3 | C51—C50—H50 | 122.1 |
C13—N14—C15 | 117.5 (3) | C49—C50—H50 | 122.1 |
C13—N14—Cu2 | 120.4 (2) | C50—C51—C52 | 120.9 (4) |
C15—N14—Cu2 | 122.1 (2) | C50—C51—H51 | 119.5 |
N14—C15—C16 | 122.2 (3) | C52—C51—H51 | 119.5 |
N14—C15—H15 | 118.9 | C53—C52—C51 | 124.0 (4) |
C16—C15—H15 | 118.9 | C53—C52—H52 | 118.0 |
C15—C16—C11 | 120.4 (3) | C51—C52—H52 | 118.0 |
C15—C16—H16 | 119.8 | C52—C53—C54 | 117.1 (4) |
C11—C16—H16 | 119.8 | C52—C53—H53 | 121.5 |
C18—N17—C18i | 118.0 (4) | C54—C53—H53 | 121.5 |
C18—N17—Cu1 | 121.02 (18) | C49—C54—C55 | 107.3 (3) |
C18i—N17—Cu1 | 121.02 (18) | C49—C54—C53 | 116.4 (4) |
N17—C18—C19 | 122.6 (3) | C55—C54—C53 | 136.3 (4) |
N17—C18—H18 | 118.7 | C56—C55—C54 | 106.4 (4) |
C19—C18—H18 | 118.7 | C56—C55—C60 | 130.6 (4) |
C18—C19—C20 | 120.3 (3) | C54—C55—C60 | 123.0 (4) |
C18—C19—H19 | 119.8 | C55—C56—O48 | 109.8 (4) |
C20—C19—H19 | 119.8 | C55—C56—C57 | 136.6 (4) |
C19—C20—C19i | 116.1 (4) | O48—C56—C57 | 113.5 (3) |
C19—C20—C21 | 121.96 (19) | O58—C57—O59 | 126.3 (4) |
C19i—C20—C21 | 121.96 (19) | O58—C57—C56 | 116.3 (3) |
C22—C21—C22i | 116.1 (4) | O59—C57—C56 | 117.5 (3) |
C22—C21—C20 | 121.94 (19) | O62—C60—O61 | 121.7 (4) |
C22i—C21—C20 | 121.9 (2) | O62—C60—C55 | 120.6 (5) |
C23—C22—C21 | 120.1 (3) | O61—C60—C55 | 117.7 (4) |
C23—C22—H22 | 119.9 | C60—O61—H61 | 108.1 |
C21—C22—H22 | 119.9 | H63A—O63—H63B | 101.2 |
N24—C23—C22 | 123.3 (3) | H64A—O64—H64B | 100.0 |
N24—C23—H23 | 118.3 | H65A—O65—H65B | 117.9 |
C22—C23—H23 | 118.3 | H66A—O66—H66B | 98.8 |
C23—N24—C23i | 116.9 (4) | H67A—O67—H67B | 111.6 |
C23—N24—Cu1iv | 121.53 (18) | | |
Symmetry codes: (i) −x+1/2, −y+1/2, z; (ii) −x+1/2, y, z−1/2; (iii) −x+1/2, −y−1/2, z; (iv) −x+1/2, y, z+1/2. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3A···O63i | 0.85 | 1.89 | 2.730 (3) | 168 |
O3—H3B···O67i | 0.85 | 1.90 | 2.738 (3) | 167 |
O4—H4A···O64 | 0.85 | 1.96 | 2.764 (3) | 159 |
O4—H4B···O63v | 0.85 | 1.99 | 2.817 (3) | 164 |
O46—H46···O43 | 0.85 | 1.56 | 2.410 (4) | 172 |
O61—H61···O59 | 0.85 | 1.74 | 2.594 (4) | 179 |
O63—H63A···O43 | 0.85 | 1.90 | 2.740 (3) | 172 |
O63—H63B···O58 | 0.85 | 1.86 | 2.702 (3) | 173 |
O64—H64A···O65 | 0.85 | 1.93 | 2.779 (4) | 174 |
O64—H64B···O66 | 0.85 | 1.97 | 2.790 (4) | 163 |
O65—H65A···O47vi | 0.85 | 1.86 | 2.711 (4) | 174 |
O65—H65B···O44 | 0.85 | 1.98 | 2.809 (4) | 164 |
O66—H66A···O44 | 0.85 | 1.95 | 2.791 (5) | 170 |
O66—H66B···O58 | 0.85 | 2.15 | 2.950 (4) | 158 |
O67—H67A···O59 | 0.85 | 2.00 | 2.853 (4) | 177 |
O67—H67B···O47vii | 0.85 | 2.06 | 2.896 (4) | 167 |
Symmetry codes: (i) −x+1/2, −y+1/2, z; (v) −x+1, y−1/2, −z+1/2; (vi) −x+1, −y, −z; (vii) x, −y+1/2, z+1/2. |
Experimental details
Crystal data |
Chemical formula | [Cu(C10H8N2)2(H2O)2](C10H5O5)2·5H2O |
Mr | 912.30 |
Crystal system, space group | Orthorhombic, Pccn |
Temperature (K) | 110 |
a, b, c (Å) | 15.8470 (2), 22.2874 (3), 22.5446 (3) |
V (Å3) | 7962.49 (18) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 0.63 |
Crystal size (mm) | 0.40 × 0.40 × 0.30 |
|
Data collection |
Diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 58792, 9629, 6077 |
Rint | 0.057 |
(sin θ/λ)max (Å−1) | 0.664 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.065, 0.210, 1.09 |
No. of reflections | 9628 |
No. of parameters | 564 |
No. of restraints | 6 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 1.97, −0.88 |
Selected geometric parameters (Å, º) topCu1—N5 | 2.024 (3) | Cu2—N14 | 2.030 (3) |
Cu1—N17 | 2.070 (3) | Cu2—N25 | 2.094 (3) |
Cu1—O3 | 2.351 (2) | Cu2—O4 | 2.380 (2) |
| | | |
N5i—Cu1—N5 | 179.76 (13) | N14iii—Cu2—N14 | 179.08 (13) |
N5—Cu1—N17 | 90.12 (7) | N14—Cu2—N32ii | 90.46 (7) |
N5—Cu1—N24ii | 89.88 (7) | N14—Cu2—N25 | 89.54 (7) |
N17—Cu1—N24ii | 180.0 | N32ii—Cu2—N25 | 180.0 |
N5i—Cu1—O3i | 88.10 (9) | N14—Cu2—O4iii | 91.68 (9) |
N5—Cu1—O3i | 91.90 (9) | N14—Cu2—O4 | 88.32 (9) |
N17—Cu1—O3i | 90.77 (5) | N25—Cu2—O4 | 89.77 (5) |
N24ii—Cu1—O3i | 89.23 (5) | O4iii—Cu2—O4 | 179.54 (10) |
O3i—Cu1—O3 | 178.46 (11) | | |
Symmetry codes: (i) −x+1/2, −y+1/2, z; (ii) −x+1/2, y, z−1/2; (iii) −x+1/2, −y−1/2, z. |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H3A···O63i | 0.85 | 1.89 | 2.730 (3) | 168 |
O3—H3B···O67i | 0.85 | 1.90 | 2.738 (3) | 167 |
O4—H4A···O64 | 0.85 | 1.96 | 2.764 (3) | 159 |
O4—H4B···O63iv | 0.85 | 1.99 | 2.817 (3) | 164 |
O46—H46···O43 | 0.85 | 1.56 | 2.410 (4) | 172 |
O61—H61···O59 | 0.85 | 1.74 | 2.594 (4) | 179 |
O63—H63A···O43 | 0.85 | 1.90 | 2.740 (3) | 172 |
O63—H63B···O58 | 0.85 | 1.86 | 2.702 (3) | 173 |
O64—H64A···O65 | 0.85 | 1.93 | 2.779 (4) | 174 |
O64—H64B···O66 | 0.85 | 1.97 | 2.790 (4) | 163 |
O65—H65A···O47v | 0.85 | 1.86 | 2.711 (4) | 174 |
O65—H65B···O44 | 0.85 | 1.98 | 2.809 (4) | 164 |
O66—H66A···O44 | 0.85 | 1.95 | 2.791 (5) | 170 |
O66—H66B···O58 | 0.85 | 2.15 | 2.950 (4) | 158 |
O67—H67A···O59 | 0.85 | 2.00 | 2.853 (4) | 177 |
O67—H67B···O47vi | 0.85 | 2.06 | 2.896 (4) | 167 |
Symmetry codes: (i) −x+1/2, −y+1/2, z; (iv) −x+1, y−1/2, −z+1/2; (v) −x+1, −y, −z; (vi) x, −y+1/2, z+1/2. |
This study is part of our investigation of the supramolecular reactivity of 1-benzofuran-2,3-dicarboxylic acid. It was shown in the preceding report (Koner & Goldberg, 2009) that one carboxylic acid group can be readily de-protonated to convert this ligand into a monoanionic species (BFDC-), while the H atom of the second carboxylic acid group is involved in an intramolecular hydrogen bond and is more difficult to ionize. It has been also shown that BFDC- can act as a good coordinating ligand, as well as a 1- counter-ion, to 2+ and 3+ transition metal cations. This includes formation of an octahedral complex, [Cu(BFDC-)2(imidazole)4] (Koner & Goldberg, 20098). In an additional experiment, the imidazole component was replaced in the reaction mixture by the 4,4'-bipyridine ligand, anticipating that the latter may provide extended connectivity features in order to afford the formation of two- or three-dimensional coordination framework instead of the discrete complexes. Coordination of BFDC- to the copper ions was also envisioned (as in the earlier example), to account for charge balance.
The asymmetric unit of the resulting multi-component product (I) is shown in Fig. 1. Its crystal structure can be best described as composed of alternating layered zones of extended coordination and hydrogen-bonded assemblies. The former features a square grid network in which the bipyridine units line the sides of the grids, while the copper ions serve as connecting nodes (Fig. 2) Each ion has an octahedral coordination environment (Table 1), where the equatorial positions are occupied by the N-sites of four adjacent bipyridine ligands. The trans-axial positions at every site are occupied by coordinated water ligands. In accordance with the Jahn–Teller effect, the octahedra are axially distorted with longer Cu—O than Cu—N bonds (Table 1). Correspondingly, each of the bipyridine spacers binds to two adjacent six-coordinated copper ions. The Cu1/N17/C18–C23/N24 entities are located on axes of twofold rotation at (1/4, 1/4, z), while the Cu2/N25/C26–C31/N32 units are positioned on twofold axes at (1/4, -1/4, z).
The coordination networks are aligned parallel to the bc plane of the crystal, being centered at x = 1/4 and x = 3/4. The size of the grid is characterized by Cu···Cu distances of 11.144 (2) and 11.275 (2) Å between the consecutive copper ions along the b and c axes, respectively. While many coordination polymers and complexes involving transition metal ions and 4,4'-bipyridine are know, those involving square-shaped arrangement of this ligand with copper ions have been published only recently. They involve, for example, the discrete cyclo-tetrakis(µ2-4,4'-bipyridine)copper(II) molecule (Dey et al., 2004) and the square grid-like copper-4,4'-bipyridine coordination layers of similar connectivity and coordination distances as observed in this study (Wang et al., 2007).
In the crystal structure, the polymeric layers shown in Fig. 2 are intercalated by parallel hydrogen-bonded layers centered at x = 0 and x = 1/2. These are composed of water molecules and the planar monoanionic benzofurandicarboxylic acid entities (see below). The latter are grouped in pairs in a partly overlapping manner across centers of inversion. The mean interplanar distances between the overlayed units are 3.56 (3) and 3.23 (3) Å for the more overlapping [across inversion at (1/2, 0, 0)] O33/C34–C41 and the less overlapping [across inversion at (1/2, 0, 1/2)] O48/C49–C56 aromatic fragments, respectively (Fig. 3). The hydrogen-bonded layers interact further with the coordination networks from above and below by additional hydrogen bonding of the O63, O64 and O67 water molecules to the Cu(H2O)2 nodes, through the coordinated O3 and O4 water ligands (Table 2). Correspondingly, the BFDC- units approach from above and below, and partly protrude into, the void segments of the adjacent coordination networks. This in turn allows the preservation of a nearly ideal square geometry of the grid, while rhombus distortion of the network to minimize the void space has frequently been observed in other framework solids (Wang et al., 2007; George et al., 2006).
A rigorous graph-set analysis (Bernstein et al., 1995) of the hydrogen-bonded networks in this structure is quite complex, as the latter involve different types of hydrogen bonds within and between the different component species. Therefore, the current discussion is limited to the type-specification of the basic localized ring patterns. The intramolecular hydrogen bonding in the BFDC- ligands is characterized by the S(7) descriptor. The association of the two anions of the asymmetric unit through the O63 and O66 water molecules, involving also atoms O43, O44 and O58, forms a ten-membered R43(10) ring with four H-atom donors and three H-atom acceptors. An adjacent ring involves the carboxylate O44 atom and the O64, O65 and O66 water molecules, and is specified as R44(8). Two further rings represent association of the anionic layers to the copper-coordinated water ligands. As shown in Fig. 3, one involves atoms O58, O59, O63, O67 and O3(-x + 1/2, -y + 1/2, z) and is defined as R44(10). The other ring is composed of atoms O4, O64, O65, O47(-x + 1, -y, -z), O3(x +1/2, -y, -z +1/2), O63(-x + 1, y - 1/2, -z +1/2) and O67 (-x + 1, y - 1/2, -z + 1/2) assembling into an R75(14) pattern. These four types of ring patterns are fused into a continuous hydrogen-bonding array, which propagates parallel to the b axis of the crystal. Similar arrays occur in a periodic manner along the ±c direction, at the interfaces between adjacent rows of the BFDC- anions.
The intercalated crystal structure of (I) is illustrated in Fig. 4.
In summary, compound (I) exhibits a framework architecture formed by an interesting combination of coordination and hydrogen-bonding networking. It is composed of alternating layers of square grid coordination polymers of the Cu(H2O)2 and bipyridine species and hydrogen-bonded assemblies of BFDC- and water molecules. These layered fragments are further interconnected to one another by hydrogen bonds from the axial copper-coordinated water ligands to water molecules of the hydrophilic zones.