Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807043905/hb2533sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807043905/hb2533Isup2.hkl |
CCDC reference: 663589
Bpa (50.0 mg) was mixed with CuCl2.2H2O (49.8 mg), in 5 ml of 80% (v/v) methanol-water solution for 5 min at room temperature (molar ratio 1:1). The aquamarine-colored precipitate was dried under a vacuum and assumed to be [Cu(bpa)Cl2]. Then, the precipitate (5.0 mg) was reacted with aspartic acid (2.0 mg) in 2.4 ml dimethylsulfoxide for 60 min at 343 K. The reaction mixture was left to stand at room temperature, and after two months, blue needles of (I) appeared from the mother liquor.
The water H atoms were located in a difference map and refined as riding in their as-found relative positions with Uiso(H) = 1.5Ueq(O).
The other H atoms were located in a difference map, relocated in idealized locations (C—H = 0.93–0.97 Å, N—H = 0.86 Å) and refined as riding with Uiso(H) = 1.2Ueq(C, N)
Recently, significant attention has focused on Cu(II) complexes in the studies of their antitumor and/or antiviral activity (Wang & Okabe, 2005; Kelland, 2005).
As part of our ongoing studies (Yodoshi et al., 2007) of mixed-ligand copper complexes, we now report the synthesis and structure of the title compound, (I), containing both aspartate (asp) anions and 2,2'-bipyridylamine (bpa) molecules (Fig. 1).
The Cu atom in (I) has a distorted square-pyramidal geometry formed by one O atom of the α-carboxylate group, one N atom of the α-amino group of an aspartate anion and two N atoms of a bidentate bpa in the basal plane and one O atom from the β-carboxylate of an aspartate in the axial position. Each complex is bridged through the O atom in the axial position, and forms polymeric chains.
Cu1 deviates by 0.289 (1) Å from the mean plane through atoms N1, N2, N4 and O1. A six-membered chelate ring Cu1/N1/C5/N3/C6/N2 and a five- membered one Cu1/O1/C11/C12/N4 are formed between the Cu1 atom and the bpa and asp ligands, respectively, where the dihedral angle between two planes, Cu1/N1/N2 and Cu1/O1/N4 is 23.1 (2)°. The two pyridine rings in the bpa ligand are also non-planar with the dihedral angle of 23.15 (8)°.
The metal coordination in (I) resembles that in monomeric Cu(asp)(bpy)H2O (Antolini et al., 1983), and the polymeric linear chain structure of (I) resembles that in [Cu(glu)(bpy)]n (Antolini et al., 1985).
The bond distances (Table 1) in the square plane in (I) are similar to those in Cu(asp)(bpy)H2O and [Cu(glu)(bpy)]n. The Cu1—O3 bond lenght is a little longer than those in the square plane because of the well known Jahn-Teller effect. The axial distance is similar to that in the polymeric complex, {Cu(glu)(bpy)]n, but a little shorter than that in Cu(asp)(bpy)H2O.
The crystal structure of (I) is stabilized by O—H···O hydrogen bonds the water molecules and the carboxylate group of asp, and N—H···O hydrogen bonds between the imino group of bpa and the carboxylate group (Table 2). Aromatic π-π stacking interactions between bpa ligands of adjacent chains also stabilizes the crystal packing (Fig. 2). The distance between the centroids of the pyridine rings Cg1 (N1/C1—C5) and Cg2 (N2/C6—C10) (symmetry code: -1/2 + x, 1/2 - y, 1 - z) is 3.699 (4) Å (Spek, 2003).
For related structures, see: Antolini et al. (1983, 1985). For background, see: Kelland (2005); Wang & Okabe (2005); Yodoshi et al. (2007).
Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku/MSC, 2005) and CRYSTALS (Betteridge et al., 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2003); software used to prepare material for publication: CrystalStructure (Rigaku/MSC, 2005).
[Cu(C4H5O4N)(C10H9N3)]·H2O | F(000) = 788.00 |
Mr = 383.86 | Dx = 1.692 Mg m−3 |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.7107 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 11236 reflections |
a = 7.018 (5) Å | θ = 3.1–27.5° |
b = 10.364 (8) Å | µ = 1.48 mm−1 |
c = 20.72 (2) Å | T = 123 K |
V = 1507 (2) Å3 | Needle, blue |
Z = 4 | 0.40 × 0.04 × 0.04 mm |
Rigaku R-AXIS RAPID diffractometer | 2022 reflections with F2 > 2.0σ(F2) |
Detector resolution: 10.00 pixels mm-1 | Rint = 0.061 |
ω scans | θmax = 27.5° |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | h = −9→8 |
Tmin = 0.931, Tmax = 0.942 | k = −13→13 |
13783 measured reflections | l = −26→26 |
3469 independent reflections |
Refinement on F2 | w = 1/[σ2(Fo2) + (0.0362P)2] where P = (Fo2 + 2Fc2)/3 |
R[F2 > 2σ(F2)] = 0.040 | (Δ/σ)max < 0.001 |
wR(F2) = 0.079 | Δρmax = 0.85 e Å−3 |
S = 0.94 | Δρmin = −0.90 e Å−3 |
3469 reflections | Absolute structure: Flack (1983), 1416 Friedel pairs |
224 parameters | Absolute structure parameter: 0.02 (2) |
H-atom parameters constrained |
[Cu(C4H5O4N)(C10H9N3)]·H2O | V = 1507 (2) Å3 |
Mr = 383.86 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 7.018 (5) Å | µ = 1.48 mm−1 |
b = 10.364 (8) Å | T = 123 K |
c = 20.72 (2) Å | 0.40 × 0.04 × 0.04 mm |
Rigaku R-AXIS RAPID diffractometer | 3469 independent reflections |
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) | 2022 reflections with F2 > 2.0σ(F2) |
Tmin = 0.931, Tmax = 0.942 | Rint = 0.061 |
13783 measured reflections |
R[F2 > 2σ(F2)] = 0.040 | H-atom parameters constrained |
wR(F2) = 0.079 | Δρmax = 0.85 e Å−3 |
S = 0.94 | Δρmin = −0.90 e Å−3 |
3469 reflections | Absolute structure: Flack (1983), 1416 Friedel pairs |
224 parameters | Absolute structure parameter: 0.02 (2) |
Geometry. ENTER SPECIAL DETAILS OF THE MOLECULAR GEOMETRY |
Refinement. Refinement using all reflections. The weighted R-factor (wR) and goodness of fit (S) are based on F2. R-factor (gt) are based on F. The threshold expression of F2 > 2.0 σ(F2) is used only for calculating R-factor (gt). |
x | y | z | Uiso*/Ueq | ||
Cu1 | 0.36399 (6) | 0.09559 (4) | 0.61800 (2) | 0.0172 (1) | |
O1 | 0.2334 (3) | −0.0709 (2) | 0.6236 (1) | 0.0242 (6) | |
O2 | 0.0185 (4) | −0.1830 (3) | 0.6789 (1) | 0.0292 (7) | |
O3 | −0.4093 (3) | 0.0429 (2) | 0.6832 (1) | 0.0209 (6) | |
O4 | −0.1666 (4) | 0.1431 (3) | 0.6343 (1) | 0.0297 (7) | |
O5 | 0.3663 (4) | 0.2681 (2) | 0.8106 (1) | 0.0279 (6) | |
N1 | 0.4276 (4) | 0.2784 (3) | 0.5966 (1) | 0.0168 (7) | |
N2 | 0.4572 (4) | 0.0421 (3) | 0.5318 (1) | 0.0178 (7) | |
N3 | 0.3895 (4) | 0.2443 (3) | 0.4851 (1) | 0.0197 (7) | |
N4 | 0.1925 (4) | 0.1424 (3) | 0.6924 (1) | 0.0177 (7) | |
C1 | 0.4647 (5) | 0.3616 (4) | 0.6454 (2) | 0.0209 (9) | |
C2 | 0.4876 (5) | 0.4911 (4) | 0.6369 (2) | 0.025 (1) | |
C3 | 0.4779 (5) | 0.5399 (4) | 0.5744 (2) | 0.0248 (9) | |
C4 | 0.4460 (5) | 0.4572 (4) | 0.5240 (2) | 0.0250 (9) | |
C5 | 0.4214 (5) | 0.3259 (3) | 0.5365 (2) | 0.0162 (8) | |
C6 | 0.4331 (5) | 0.1137 (4) | 0.4789 (2) | 0.0193 (8) | |
C7 | 0.4491 (5) | 0.0626 (4) | 0.4165 (2) | 0.0230 (9) | |
C8 | 0.4944 (5) | −0.0649 (4) | 0.4100 (2) | 0.0271 (9) | |
C9 | 0.5273 (5) | −0.1404 (4) | 0.4643 (2) | 0.0250 (9) | |
C10 | 0.5064 (5) | −0.0835 (4) | 0.5240 (2) | 0.0235 (8) | |
C11 | 0.1157 (5) | −0.0845 (3) | 0.6693 (2) | 0.0213 (8) | |
C12 | 0.0989 (5) | 0.0253 (3) | 0.7183 (2) | 0.0174 (8) | |
C13 | −0.1098 (5) | 0.0490 (3) | 0.7371 (2) | 0.0178 (8) | |
C14 | −0.2371 (5) | 0.0801 (4) | 0.6797 (2) | 0.0189 (8) | |
H1 | 0.4750 | 0.3286 | 0.6870 | 0.025* | |
H2 | 0.5091 | 0.5454 | 0.6719 | 0.030* | |
H3 | 0.4930 | 0.6278 | 0.5670 | 0.030* | |
H4 | 0.4407 | 0.4882 | 0.4819 | 0.030* | |
H5 | 0.4294 | 0.1143 | 0.3804 | 0.028* | |
H6 | 0.5034 | −0.1013 | 0.3691 | 0.033* | |
H7 | 0.5622 | −0.2266 | 0.4605 | 0.030* | |
H8 | 0.5271 | −0.1335 | 0.5605 | 0.028* | |
H9 | 0.3351 | 0.2789 | 0.4522 | 0.024* | |
H10 | 0.2615 | 0.1804 | 0.7237 | 0.021* | |
H11 | 0.1034 | 0.1988 | 0.6790 | 0.021* | |
H12 | 0.1678 | −0.0007 | 0.7574 | 0.021* | |
H13 | −0.1588 | −0.0272 | 0.7586 | 0.021* | |
H14 | −0.1153 | 0.1200 | 0.7675 | 0.021* | |
H15 | 0.4061 | 0.3424 | 0.8139 | 0.042* | |
H16 | 0.2480 | 0.2763 | 0.8131 | 0.042* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Cu1 | 0.0183 (2) | 0.0164 (2) | 0.0169 (2) | −0.0009 (2) | 0.0007 (2) | −0.0000 (2) |
O1 | 0.024 (1) | 0.021 (1) | 0.028 (2) | −0.005 (1) | 0.010 (1) | −0.002 (1) |
O2 | 0.029 (2) | 0.017 (1) | 0.042 (2) | −0.002 (1) | 0.009 (1) | 0.001 (1) |
O3 | 0.017 (1) | 0.024 (1) | 0.022 (1) | −0.002 (1) | −0.001 (1) | 0.004 (1) |
O4 | 0.023 (1) | 0.046 (2) | 0.021 (2) | −0.006 (1) | 0.000 (1) | 0.018 (1) |
O5 | 0.027 (1) | 0.019 (1) | 0.038 (2) | 0.002 (2) | −0.002 (2) | −0.005 (1) |
N1 | 0.015 (1) | 0.018 (2) | 0.018 (2) | −0.002 (1) | −0.001 (1) | −0.001 (1) |
N2 | 0.021 (2) | 0.018 (2) | 0.014 (2) | −0.003 (1) | 0.000 (1) | 0.002 (1) |
N3 | 0.023 (2) | 0.020 (2) | 0.015 (2) | 0.001 (2) | −0.005 (1) | 0.004 (1) |
N4 | 0.015 (1) | 0.017 (2) | 0.021 (2) | −0.002 (1) | −0.001 (1) | −0.003 (1) |
C1 | 0.017 (2) | 0.025 (2) | 0.020 (2) | −0.002 (2) | 0.001 (2) | −0.002 (2) |
C2 | 0.019 (2) | 0.022 (2) | 0.033 (3) | −0.006 (2) | 0.002 (2) | −0.010 (2) |
C3 | 0.027 (2) | 0.017 (2) | 0.030 (2) | −0.001 (2) | 0.002 (2) | 0.003 (2) |
C4 | 0.020 (2) | 0.024 (2) | 0.031 (2) | 0.003 (2) | 0.005 (2) | 0.004 (2) |
C5 | 0.014 (2) | 0.018 (2) | 0.017 (2) | 0.004 (2) | 0.000 (2) | 0.000 (2) |
C6 | 0.014 (2) | 0.023 (2) | 0.020 (2) | −0.004 (2) | 0.001 (1) | −0.002 (2) |
C7 | 0.025 (2) | 0.026 (2) | 0.018 (2) | −0.007 (2) | 0.001 (2) | −0.000 (2) |
C8 | 0.031 (2) | 0.032 (3) | 0.018 (2) | −0.006 (2) | 0.004 (2) | −0.006 (2) |
C9 | 0.032 (2) | 0.020 (2) | 0.023 (2) | −0.004 (2) | 0.009 (2) | −0.004 (2) |
C10 | 0.025 (2) | 0.021 (2) | 0.025 (2) | −0.001 (2) | 0.004 (2) | 0.005 (2) |
C11 | 0.018 (2) | 0.012 (2) | 0.034 (2) | −0.002 (2) | −0.005 (2) | 0.005 (2) |
C12 | 0.017 (2) | 0.018 (2) | 0.017 (2) | −0.002 (2) | −0.001 (2) | 0.004 (1) |
C13 | 0.018 (2) | 0.019 (2) | 0.016 (2) | −0.003 (2) | 0.001 (2) | −0.001 (1) |
C14 | 0.016 (2) | 0.019 (2) | 0.022 (2) | 0.002 (2) | −0.002 (1) | −0.003 (2) |
Cu1—O1 | 1.958 (2) | C2—C3 | 1.391 (6) |
Cu1—O3i | 2.157 (2) | C2—H2 | 0.9300 |
Cu1—N1 | 1.997 (3) | C3—C4 | 1.370 (6) |
Cu1—N2 | 1.981 (3) | C3—H3 | 0.9300 |
Cu1—N4 | 2.015 (3) | C4—C5 | 1.396 (5) |
O1—C11 | 1.264 (4) | C4—H4 | 0.9302 |
O2—C11 | 1.245 (4) | C6—C7 | 1.402 (5) |
O3—Cu1ii | 2.157 (2) | C7—C8 | 1.366 (6) |
O3—C14 | 1.271 (4) | C7—H5 | 0.9300 |
O4—C14 | 1.247 (4) | C8—C9 | 1.390 (5) |
O5—H15 | 0.8220 | C8—H6 | 0.9300 |
O5—H16 | 0.8365 | C9—C10 | 1.377 (5) |
N1—C1 | 1.354 (5) | C9—H7 | 0.9301 |
N1—C5 | 1.340 (5) | C10—H8 | 0.9300 |
N2—C6 | 1.335 (5) | C11—O1 | 1.264 (4) |
N2—C10 | 1.357 (5) | C11—O2 | 1.245 (4) |
N3—C5 | 1.378 (5) | C11—C12 | 1.530 (5) |
N3—C6 | 1.394 (5) | C12—C11 | 1.530 (5) |
N3—H9 | 0.8599 | C12—C13 | 1.535 (5) |
N4—C12 | 1.482 (4) | C12—H12 | 0.9800 |
N4—H10 | 0.9001 | C13—C14 | 1.522 (5) |
N4—H11 | 0.9000 | C13—H13 | 0.9700 |
C1—C2 | 1.363 (5) | C13—H14 | 0.9700 |
C1—H1 | 0.9300 | H16—O5 | 0.8365 |
O1—Cu1—O3i | 94.9 (1) | C4—C3—C2 | 119.3 (4) |
O1—Cu1—N1 | 162.7 (1) | C4—C3—H3 | 120.3422 |
O1—Cu1—N2 | 87.8 (1) | H3—C3—C2 | 120.3249 |
O1—Cu1—N4 | 83.5 (1) | C5—C4—C3 | 119.3 (4) |
O3i—Cu1—N1 | 102.4 (1) | C5—C4—H4 | 120.3693 |
O3i—Cu1—N2 | 104.5 (1) | H4—C4—C3 | 120.3705 |
O3i—Cu1—N4 | 91.3 (1) | C7—C6—N2 | 122.5 (3) |
N1—Cu1—N2 | 89.5 (1) | C7—C6—N3 | 118.0 (3) |
N1—Cu1—N4 | 94.3 (1) | C8—C7—C6 | 118.3 (3) |
N2—Cu1—N4 | 162.6 (1) | C8—C7—H5 | 120.8306 |
C11—O1—Cu1 | 116.6 (2) | H5—C7—C6 | 120.8366 |
Cu1ii—O3—C14 | 126.1 (2) | C9—C8—C7 | 120.3 (4) |
H15—O5—H16 | 103.7063 | C9—C8—H6 | 119.8735 |
C1—N1—Cu1 | 118.8 (2) | H6—C8—C7 | 119.8668 |
C1—N1—C5 | 117.8 (3) | C10—C9—C8 | 117.9 (4) |
C5—N1—Cu1 | 123.2 (2) | C10—C9—H7 | 121.0512 |
C6—N2—Cu1 | 122.9 (2) | H7—C9—C8 | 121.0527 |
C6—N2—C10 | 117.8 (3) | H8—C10—N2 | 118.4655 |
C10—N2—Cu1 | 117.4 (2) | H8—C10—C9 | 118.4670 |
C5—N3—C6 | 129.2 (3) | O1—C11—C12 | 117.7 (3) |
C5—N3—H9 | 115.4117 | O1—C11—O2 | 124.7 (3) |
C6—N3—H9 | 115.4095 | O2—C11—C12 | 117.5 (3) |
C12—N4—Cu1 | 110.2 (2) | C11—C12—N4 | 109.5 (3) |
C12—N4—H10 | 109.6151 | C11—C12—H12 | 107.8129 |
C12—N4—H11 | 109.6255 | C11—C12—C13 | 111.1 (3) |
H10—N4—Cu1 | 109.6205 | C13—C12—N4 | 112.5 (3) |
H10—N4—H11 | 108.1428 | C13—C12—H12 | 107.8132 |
H11—N4—Cu1 | 109.6256 | H12—C12—N4 | 107.8176 |
C2—C1—N1 | 123.5 (4) | C14—C13—C12 | 113.3 (3) |
C2—C1—H1 | 118.2291 | C14—C13—H13 | 108.8942 |
H1—C1—N1 | 118.2395 | C14—C13—H14 | 108.9045 |
C3—C2—C1 | 118.2 (4) | H13—C13—C12 | 108.9037 |
C3—C2—H2 | 120.8867 | H13—C13—H14 | 107.7389 |
H2—C2—C1 | 120.8839 | H14—C13—C12 | 108.9029 |
N1—Cu1—O1—C11 | −87.8 (4) | N1—C1—C2—C3 | −1.9 (6) |
O1—Cu1—N1—C1 | 124.4 (3) | C1—C2—C3—C4 | 0.0 (5) |
O1—Cu1—N2—C6 | 126.6 (3) | C2—C3—C4—C5 | 0.8 (5) |
O1—Cu1—N4—C12 | 11.8 (2) | C3—C4—C5—N1 | 0.2 (4) |
Cu1—O1—C11—O2 | 178.5 (3) | C3—C4—C5—N3 | −179.9 (2) |
Cu1—N1—C1—C2 | −172.1 (3) | N2—C6—C7—C8 | −1.1 (5) |
Cu1—N1—C5—N3 | −7.1 (4) | C6—C7—C8—C9 | −1.3 (5) |
Cu1—N1—C5—C4 | 172.7 (3) | C7—C8—C9—C10 | 2.1 (6) |
Cu1—N2—C6—N3 | 18.2 (4) | C8—C9—C10—N2 | −0.5 (6) |
Cu1—N2—C10—C9 | 163.3 (3) | O1—C11—C12—N4 | 14.4 (4) |
C6—N3—C5—N1 | −28.1 (5) | O2—C11—C12—N4 | −168.6 (3) |
C6—N3—C5—C4 | 152.1 (3) | N4—C12—C13—C14 | 65.7 (4) |
C5—N3—C6—N2 | 22.1 (5) | C12—C13—C14—O3 | 147.9 (3) |
Cu1—N4—C12—C11 | −16.4 (3) | C12—C13—C14—O4 | −34.3 (5) |
Symmetry codes: (i) x+1, y, z; (ii) x−1, y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H9···O4iii | 0.86 | 1.97 | 2.763 (4) | 153 |
N4—H10···O5 | 0.90 | 2.15 | 3.031 (4) | 166 |
N4—H11···O4 | 0.90 | 2.19 | 2.793 (4) | 124 |
O5—H15···O3iv | 0.82 | 2.08 | 2.867 (3) | 160 |
O5—H16···O2iv | 0.84 | 1.92 | 2.756 (4) | 173 |
Symmetry codes: (iii) x+1/2, −y+1/2, −z+1; (iv) −x, y+1/2, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | [Cu(C4H5O4N)(C10H9N3)]·H2O |
Mr | 383.86 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 123 |
a, b, c (Å) | 7.018 (5), 10.364 (8), 20.72 (2) |
V (Å3) | 1507 (2) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 1.48 |
Crystal size (mm) | 0.40 × 0.04 × 0.04 |
Data collection | |
Diffractometer | Rigaku R-AXIS RAPID |
Absorption correction | Multi-scan (ABSCOR; Higashi, 1995) |
Tmin, Tmax | 0.931, 0.942 |
No. of measured, independent and observed [F2 > 2.0σ(F2)] reflections | 13783, 3469, 2022 |
Rint | 0.061 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.079, 0.94 |
No. of reflections | 3469 |
No. of parameters | 224 |
No. of restraints | ? |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.85, −0.90 |
Absolute structure | Flack (1983), 1416 Friedel pairs |
Absolute structure parameter | 0.02 (2) |
Computer programs: RAPID-AUTO (Rigaku, 1998), CrystalStructure (Rigaku/MSC, 2005) and CRYSTALS (Betteridge et al., 2003), SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), ORTEP-3 (Farrugia, 1997) and PLATON (Spek, 2003), CrystalStructure (Rigaku/MSC, 2005).
Cu1—O1 | 1.958 (2) | Cu1—N2 | 1.981 (3) |
Cu1—O3i | 2.157 (2) | Cu1—N4 | 2.015 (3) |
Cu1—N1 | 1.997 (3) |
Symmetry code: (i) x+1, y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H9···O4ii | 0.86 | 1.97 | 2.763 (4) | 153 |
N4—H10···O5 | 0.90 | 2.15 | 3.031 (4) | 166 |
N4—H11···O4 | 0.90 | 2.19 | 2.793 (4) | 124 |
O5—H15···O3iii | 0.82 | 2.08 | 2.867 (3) | 160 |
O5—H16···O2iii | 0.84 | 1.92 | 2.756 (4) | 173 |
Symmetry codes: (ii) x+1/2, −y+1/2, −z+1; (iii) −x, y+1/2, −z+3/2. |
Recently, significant attention has focused on Cu(II) complexes in the studies of their antitumor and/or antiviral activity (Wang & Okabe, 2005; Kelland, 2005).
As part of our ongoing studies (Yodoshi et al., 2007) of mixed-ligand copper complexes, we now report the synthesis and structure of the title compound, (I), containing both aspartate (asp) anions and 2,2'-bipyridylamine (bpa) molecules (Fig. 1).
The Cu atom in (I) has a distorted square-pyramidal geometry formed by one O atom of the α-carboxylate group, one N atom of the α-amino group of an aspartate anion and two N atoms of a bidentate bpa in the basal plane and one O atom from the β-carboxylate of an aspartate in the axial position. Each complex is bridged through the O atom in the axial position, and forms polymeric chains.
Cu1 deviates by 0.289 (1) Å from the mean plane through atoms N1, N2, N4 and O1. A six-membered chelate ring Cu1/N1/C5/N3/C6/N2 and a five- membered one Cu1/O1/C11/C12/N4 are formed between the Cu1 atom and the bpa and asp ligands, respectively, where the dihedral angle between two planes, Cu1/N1/N2 and Cu1/O1/N4 is 23.1 (2)°. The two pyridine rings in the bpa ligand are also non-planar with the dihedral angle of 23.15 (8)°.
The metal coordination in (I) resembles that in monomeric Cu(asp)(bpy)H2O (Antolini et al., 1983), and the polymeric linear chain structure of (I) resembles that in [Cu(glu)(bpy)]n (Antolini et al., 1985).
The bond distances (Table 1) in the square plane in (I) are similar to those in Cu(asp)(bpy)H2O and [Cu(glu)(bpy)]n. The Cu1—O3 bond lenght is a little longer than those in the square plane because of the well known Jahn-Teller effect. The axial distance is similar to that in the polymeric complex, {Cu(glu)(bpy)]n, but a little shorter than that in Cu(asp)(bpy)H2O.
The crystal structure of (I) is stabilized by O—H···O hydrogen bonds the water molecules and the carboxylate group of asp, and N—H···O hydrogen bonds between the imino group of bpa and the carboxylate group (Table 2). Aromatic π-π stacking interactions between bpa ligands of adjacent chains also stabilizes the crystal packing (Fig. 2). The distance between the centroids of the pyridine rings Cg1 (N1/C1—C5) and Cg2 (N2/C6—C10) (symmetry code: -1/2 + x, 1/2 - y, 1 - z) is 3.699 (4) Å (Spek, 2003).