Aqua{4,4′-dimethoxy-2,2′-[1,2-phenylenebis(nitrilomethylidyne)]diphenolato-κ4O,O′,N,N′}zinc(II)
Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536807022064/ng2265sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536807022064/ng2265Isup2.hkl |
CCDC reference: 650613
The title compound (I) was synthesized by adding 5-methoxy-2-hydroxybenzaldehyde (0.610 g, 4 mmol) to a solution of o-phenylenediamine (0.216 g, 2 mmol) in ethanol 95% (20 ml). The mixture was refluxed with stirring for half an hour. Zinc chloride (0.272 g, 2 mmol) in ethanol (10 ml) was then added, followed by triethylamine (0.5 ml,3.6 mmol). The mixture was stirred at room temperature for two h. An orange-red precipitate was obtained; this was washed by about 5 ml e thanol, dried, and then washed by copious amount of diethyl ether. This precipitate was then dissolved in 25 ml of pyridine. Red single crystals were formed after two months.
The water hydrogen atoms were located in a difference map and were restrained with an O1W—H distance of 0.82 Å. All other H atoms were positioned geometrically and allowed to ride on their parent atoms with C—H distances in the range 0.93–0.96 Å. The Uiso values were constrained to be 1.5Ueq of the carrier atom for methyl H atoms and 1.2Ueq for the remaining H atoms. A rotating group model was used for the methyl groups; 1573 Friedel pairs were used to determine the absolute structure.
It is well known that zinc complexes with Schiff-bases are active in biological systems and show very good activity against the leukemic cell (Tarafder et al., 2002). Recently, we reported the crystal structure of {2,2'-[1,2-phenylenebis(nitrilomethylidyne)]diphenolato- κ4O,N,N',O'}(pyridine-κN)zinc(II) (Eltayeb et al., 2007). Herein, we report the crystal structure of (I).
In (I), the Zn1 and O1W atoms lie on a mirror plane and the asymmetric unit therefore contains only half of the molecule. The tetradentate Schiff-base ligand is almost planar with a maximum deviation from the C1–C10/O1–O2/N1 plane of 0.053 (3) Å for atom N1. The methoxy group is slightly twisted from the C1–C10/O1–O2/N1 mean plane as indicated by the torsion angle C11/O2/C4/C5 of -9.6 (2)°. The ligand is coordinated to Zn1 as a tetradentate ligand via through two N and two O donor atoms, resulting in a square-pyramidal ZnII center whose fifth (axial) position is occupied by a water molecule (Fig. 1). The four atoms N1, O1, N1i and O1i [i = -x, y, z] form the basal plane, and the ZnII is displaced 0.044 (7) Å out of this mean basal plane towards the axial water molecule. Bond lengths and angles observed in the structure are normal (Allen et al., 1987).
In the crystal of (I) in Fig. 2, the water molecule is involved in an intermolecular O—H···O hydrogen bond [O1W—H1W···O1; symmetry code x, -1 + y, +z] and the ligand is involved in weak C—H···O intermolecular interaction [C7—H7A···O2; symmetry code 1/2 - x, -y, -1/2 + z] (Table 2). The molcecules are linked into chains along the b axis. These chains are further interconnected in a zig-zag manner into a three-dimensional network.
For related literature on values of bond lengths and angles, see: Allen et al. (1987). For related structures, see, for example: Humphrey et al. (1999); Eltayeb, Teoh, Ng et al. (2007); Eltayeb, Teoh, Fun et al. (2007). For related literature, see: Tarafder et al. (2002).
Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2; data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 1998); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2003).
[Zn(C22H18N2O4)(H2O)] | F(000) = 472 |
Mr = 457.79 | Dx = 1.668 Mg m−3 |
Orthorhombic, Pmn21 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac -2 | Cell parameters from 3359 reflections |
a = 23.3617 (7) Å | θ = 1.7–32.5° |
b = 4.9121 (1) Å | µ = 1.39 mm−1 |
c = 7.9431 (2) Å | T = 100 K |
V = 911.51 (4) Å3 | Plate, red |
Z = 2 | 0.38 × 0.23 × 0.10 mm |
Bruker SMART APEX2 CCD area-detector diffractometer | 3359 independent reflections |
Radiation source: fine-focus sealed tube | 3179 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.047 |
Detector resolution: 8.33 pixels mm-1 | θmax = 32.5°, θmin = 1.7° |
ω scans | h = −35→35 |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | k = −7→7 |
Tmin = 0.623, Tmax = 0.874 | l = −12→12 |
29716 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.027 | H-atom parameters constrained |
wR(F2) = 0.082 | w = 1/[σ2(Fo2) + (0.0476P)2] where P = (Fo2 + 2Fc2)/3 |
S = 1.16 | (Δ/σ)max < 0.001 |
3359 reflections | Δρmax = 0.49 e Å−3 |
141 parameters | Δρmin = −0.70 e Å−3 |
2 restraints | Absolute structure: Flack (1983) |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.012 (10) |
[Zn(C22H18N2O4)(H2O)] | V = 911.51 (4) Å3 |
Mr = 457.79 | Z = 2 |
Orthorhombic, Pmn21 | Mo Kα radiation |
a = 23.3617 (7) Å | µ = 1.39 mm−1 |
b = 4.9121 (1) Å | T = 100 K |
c = 7.9431 (2) Å | 0.38 × 0.23 × 0.10 mm |
Bruker SMART APEX2 CCD area-detector diffractometer | 3359 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2005) | 3179 reflections with I > 2σ(I) |
Tmin = 0.623, Tmax = 0.874 | Rint = 0.047 |
29716 measured reflections |
R[F2 > 2σ(F2)] = 0.027 | H-atom parameters constrained |
wR(F2) = 0.082 | Δρmax = 0.49 e Å−3 |
S = 1.16 | Δρmin = −0.70 e Å−3 |
3359 reflections | Absolute structure: Flack (1983) |
141 parameters | Absolute structure parameter: 0.012 (10) |
2 restraints |
Experimental. The low-temparture data was collected with the Oxford Cyrosystem Cobra low-temperature attachment. |
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. |
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger. |
x | y | z | Uiso*/Ueq | ||
Zn1 | 0.0000 | 0.05705 (5) | 0.10449 (4) | 0.01253 (7) | |
O1 | 0.06065 (5) | 0.3095 (3) | 0.17986 (17) | 0.0153 (2) | |
O2 | 0.29634 (5) | 0.2460 (3) | 0.13415 (15) | 0.0170 (3) | |
O1W | 0.0000 | −0.2503 (4) | 0.2826 (2) | 0.0169 (3) | |
H1W1 | 0.0270 | −0.3532 | 0.2651 | 0.058 (11)* | |
C1 | 0.11623 (7) | 0.2828 (4) | 0.1586 (2) | 0.0133 (3) | |
C2 | 0.15306 (8) | 0.4597 (3) | 0.2488 (2) | 0.0146 (3) | |
H2A | 0.1369 | 0.5913 | 0.3184 | 0.017* | |
C3 | 0.21158 (8) | 0.4445 (3) | 0.2376 (2) | 0.0148 (3) | |
H3A | 0.2343 | 0.5649 | 0.2985 | 0.018* | |
C4 | 0.23727 (7) | 0.2473 (4) | 0.1342 (2) | 0.0143 (3) | |
C5 | 0.20328 (7) | 0.0725 (3) | 0.0424 (2) | 0.0133 (3) | |
H5A | 0.2203 | −0.0567 | −0.0270 | 0.016* | |
C6 | 0.14266 (7) | 0.0866 (3) | 0.0522 (2) | 0.0128 (3) | |
C7 | 0.11221 (7) | −0.1066 (4) | −0.0513 (2) | 0.0136 (3) | |
H7A | 0.1340 | −0.2240 | −0.1170 | 0.016* | |
C8 | 0.03036 (6) | −0.3179 (3) | −0.1707 (2) | 0.0127 (3) | |
C9 | 0.05973 (7) | −0.4942 (4) | −0.2795 (2) | 0.0152 (3) | |
H9A | 0.0995 | −0.4962 | −0.2795 | 0.018* | |
N1 | 0.05703 (6) | −0.1304 (3) | −0.06032 (18) | 0.0128 (3) | |
C10 | 0.02998 (6) | −0.6654 (3) | −0.3870 (3) | 0.0156 (3) | |
H10A | 0.0499 | −0.7806 | −0.4593 | 0.019* | |
C11 | 0.32314 (8) | 0.0220 (4) | 0.0525 (3) | 0.0185 (3) | |
H11A | 0.3638 | 0.0333 | 0.0678 | 0.028* | |
H11B | 0.3144 | 0.0266 | −0.0655 | 0.028* | |
H11C | 0.3093 | −0.1451 | 0.1002 | 0.028* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Zn1 | 0.01071 (11) | 0.01086 (11) | 0.01601 (12) | 0.000 | 0.000 | −0.00136 (12) |
O1 | 0.0101 (5) | 0.0129 (5) | 0.0231 (6) | −0.0003 (4) | −0.0004 (4) | −0.0032 (5) |
O2 | 0.0102 (5) | 0.0185 (6) | 0.0223 (8) | −0.0005 (4) | −0.0013 (4) | −0.0038 (5) |
O1W | 0.0191 (8) | 0.0129 (8) | 0.0188 (8) | 0.000 | 0.000 | 0.0001 (7) |
C1 | 0.0123 (7) | 0.0122 (7) | 0.0154 (7) | 0.0004 (5) | −0.0006 (5) | 0.0012 (5) |
C2 | 0.0133 (7) | 0.0113 (7) | 0.0191 (8) | 0.0007 (5) | −0.0001 (6) | −0.0014 (6) |
C3 | 0.0134 (7) | 0.0130 (8) | 0.0179 (8) | −0.0021 (5) | −0.0013 (6) | −0.0006 (6) |
C4 | 0.0116 (6) | 0.0137 (7) | 0.0176 (10) | 0.0004 (5) | −0.0010 (5) | 0.0009 (5) |
C5 | 0.0102 (6) | 0.0136 (7) | 0.0161 (7) | 0.0003 (5) | 0.0010 (5) | −0.0003 (6) |
C6 | 0.0110 (7) | 0.0129 (7) | 0.0144 (6) | −0.0008 (5) | −0.0011 (5) | 0.0005 (5) |
C7 | 0.0122 (7) | 0.0147 (7) | 0.0140 (7) | −0.0005 (5) | 0.0010 (6) | −0.0007 (5) |
C8 | 0.0122 (7) | 0.0118 (7) | 0.0141 (7) | −0.0010 (5) | −0.0001 (5) | 0.0001 (6) |
C9 | 0.0118 (7) | 0.0176 (7) | 0.0161 (8) | 0.0010 (6) | 0.0004 (6) | −0.0017 (6) |
N1 | 0.0122 (6) | 0.0116 (6) | 0.0147 (6) | −0.0009 (5) | −0.0006 (5) | −0.0014 (5) |
C10 | 0.0148 (6) | 0.0149 (6) | 0.0170 (7) | 0.0013 (5) | 0.0014 (8) | −0.0040 (8) |
C11 | 0.0133 (7) | 0.0178 (8) | 0.0244 (9) | 0.0005 (6) | 0.0002 (6) | −0.0018 (6) |
Zn1—O1 | 1.9758 (12) | C5—C6 | 1.420 (2) |
Zn1—O1i | 1.9758 (12) | C5—H5A | 0.9300 |
Zn1—O1W | 2.069 (2) | C6—C7 | 1.443 (2) |
Zn1—N1 | 2.0825 (14) | C7—N1 | 1.296 (2) |
Zn1—N1i | 2.0826 (14) | C7—H7A | 0.9300 |
O1—C1 | 1.316 (2) | C8—C9 | 1.403 (2) |
O2—C4 | 1.3800 (19) | C8—N1 | 1.416 (2) |
O2—C11 | 1.422 (2) | C8—C8i | 1.419 (3) |
O1W—H1W1 | 0.8200 | C9—C10 | 1.385 (3) |
C1—C2 | 1.417 (2) | C9—H9A | 0.9300 |
C1—C6 | 1.423 (2) | C10—C10i | 1.401 (3) |
C2—C3 | 1.372 (2) | C10—H10A | 0.9300 |
C2—H2A | 0.9300 | C11—H11A | 0.9600 |
C3—C4 | 1.404 (2) | C11—H11B | 0.9600 |
C3—H3A | 0.9300 | C11—H11C | 0.9600 |
C4—C5 | 1.379 (2) | ||
O1—Zn1—O1i | 91.64 (7) | C4—C5—H5A | 119.5 |
O1—Zn1—O1W | 104.52 (6) | C6—C5—H5A | 119.5 |
O1i—Zn1—O1W | 104.52 (6) | C5—C6—C1 | 119.90 (15) |
O1—Zn1—N1 | 90.52 (6) | C5—C6—C7 | 115.35 (15) |
O1i—Zn1—N1 | 157.94 (6) | C1—C6—C7 | 124.75 (16) |
O1W—Zn1—N1 | 96.16 (6) | N1—C7—C6 | 125.52 (16) |
O1—Zn1—N1i | 157.94 (6) | N1—C7—H7A | 117.2 |
O1i—Zn1—N1i | 90.52 (6) | C6—C7—H7A | 117.2 |
O1W—Zn1—N1i | 96.16 (6) | C9—C8—N1 | 124.60 (14) |
N1—Zn1—N1i | 79.56 (8) | C9—C8—C8i | 119.28 (10) |
C1—O1—Zn1 | 127.32 (11) | N1—C8—C8i | 116.10 (8) |
C4—O2—C11 | 116.36 (14) | C10—C9—C8 | 120.61 (15) |
Zn1—O1W—H1W1 | 109.5 | C10—C9—H9A | 119.7 |
O1—C1—C2 | 118.24 (16) | C8—C9—H9A | 119.7 |
O1—C1—C6 | 124.88 (16) | C7—N1—C8 | 122.04 (15) |
C2—C1—C6 | 116.87 (15) | C7—N1—Zn1 | 124.16 (12) |
C3—C2—C1 | 122.59 (16) | C8—N1—Zn1 | 113.29 (10) |
C3—C2—H2A | 118.7 | C9—C10—C10i | 120.11 (10) |
C1—C2—H2A | 118.7 | C9—C10—H10A | 119.9 |
C2—C3—C4 | 120.10 (16) | C10i—C10—H10A | 119.9 |
C2—C3—H3A | 119.9 | O2—C11—H11A | 109.5 |
C4—C3—H3A | 119.9 | O2—C11—H11B | 109.5 |
C5—C4—O2 | 124.95 (15) | H11A—C11—H11B | 109.5 |
C5—C4—C3 | 119.53 (15) | O2—C11—H11C | 109.5 |
O2—C4—C3 | 115.52 (15) | H11A—C11—H11C | 109.5 |
C4—C5—C6 | 120.99 (16) | H11B—C11—H11C | 109.5 |
O1i—Zn1—O1—C1 | −174.80 (12) | C2—C1—C6—C7 | −178.82 (16) |
O1W—Zn1—O1—C1 | 79.74 (15) | C5—C6—C7—N1 | 179.40 (17) |
N1—Zn1—O1—C1 | −16.75 (15) | C1—C6—C7—N1 | −0.8 (3) |
N1i—Zn1—O1—C1 | −79.4 (2) | N1—C8—C9—C10 | −178.03 (17) |
Zn1—O1—C1—C2 | −168.48 (12) | C8i—C8—C9—C10 | 0.5 (2) |
Zn1—O1—C1—C6 | 10.9 (3) | C6—C7—N1—C8 | 177.22 (16) |
O1—C1—C2—C3 | 178.75 (17) | C6—C7—N1—Zn1 | −11.6 (3) |
C6—C1—C2—C3 | −0.7 (3) | C9—C8—N1—C7 | 0.1 (3) |
C1—C2—C3—C4 | −0.3 (3) | C8i—C8—N1—C7 | −178.52 (13) |
C11—O2—C4—C5 | −9.7 (2) | C9—C8—N1—Zn1 | −172.00 (14) |
C11—O2—C4—C3 | 170.21 (16) | C8i—C8—N1—Zn1 | 9.43 (12) |
C2—C3—C4—C5 | 1.0 (3) | O1—Zn1—N1—C7 | 16.93 (15) |
C2—C3—C4—O2 | −178.87 (16) | O1i—Zn1—N1—C7 | 112.60 (18) |
O2—C4—C5—C6 | 179.13 (15) | O1W—Zn1—N1—C7 | −87.74 (15) |
C3—C4—C5—C6 | −0.7 (3) | N1i—Zn1—N1—C7 | 177.11 (12) |
C4—C5—C6—C1 | −0.3 (3) | O1—Zn1—N1—C8 | −171.21 (12) |
C4—C5—C6—C7 | 179.54 (16) | O1i—Zn1—N1—C8 | −75.55 (19) |
O1—C1—C6—C5 | −178.45 (16) | O1W—Zn1—N1—C8 | 84.12 (11) |
C2—C1—C6—C5 | 1.0 (2) | N1i—Zn1—N1—C8 | −11.03 (14) |
O1—C1—C6—C7 | 1.8 (3) | C8—C9—C10—C10i | −0.5 (2) |
Symmetry code: (i) −x, y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—H1W1···O1ii | 0.82 | 1.96 | 2.711 (2) | 153 |
C7—H7A···O2iii | 0.94 | 2.56 | 3.358 (2) | 144 |
Symmetry codes: (ii) x, y−1, z; (iii) −x+1/2, −y, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | [Zn(C22H18N2O4)(H2O)] |
Mr | 457.79 |
Crystal system, space group | Orthorhombic, Pmn21 |
Temperature (K) | 100 |
a, b, c (Å) | 23.3617 (7), 4.9121 (1), 7.9431 (2) |
V (Å3) | 911.51 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 1.39 |
Crystal size (mm) | 0.38 × 0.23 × 0.10 |
Data collection | |
Diffractometer | Bruker SMART APEX2 CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2005) |
Tmin, Tmax | 0.623, 0.874 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 29716, 3359, 3179 |
Rint | 0.047 |
(sin θ/λ)max (Å−1) | 0.756 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.027, 0.082, 1.16 |
No. of reflections | 3359 |
No. of parameters | 141 |
No. of restraints | 2 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.49, −0.70 |
Absolute structure | Flack (1983) |
Absolute structure parameter | 0.012 (10) |
Computer programs: APEX2 (Bruker, 2005), APEX2, SAINT (Bruker, 2005), SHELXTL (Sheldrick, 1998), SHELXTL and PLATON (Spek, 2003).
Zn1—O1 | 1.9758 (12) | Zn1—N1 | 2.0825 (14) |
Zn1—O1W | 2.069 (2) | ||
O1—Zn1—O1i | 91.64 (7) | O1—Zn1—N1 | 90.52 (6) |
O1—Zn1—O1W | 104.52 (6) | O1W—Zn1—N1 | 96.16 (6) |
C11—O2—C4—C5 | −9.7 (2) | C11—O2—C4—C3 | 170.21 (16) |
Symmetry code: (i) −x, y, z. |
D—H···A | D—H | H···A | D···A | D—H···A |
O1W—H1W1···O1ii | 0.82 | 1.9549 | 2.711 (2) | 153 |
C7—H7A···O2iii | 0.935 | 2.5626 | 3.358 (2) | 144 |
Symmetry codes: (ii) x, y−1, z; (iii) −x+1/2, −y, z−1/2. |
It is well known that zinc complexes with Schiff-bases are active in biological systems and show very good activity against the leukemic cell (Tarafder et al., 2002). Recently, we reported the crystal structure of {2,2'-[1,2-phenylenebis(nitrilomethylidyne)]diphenolato- κ4O,N,N',O'}(pyridine-κN)zinc(II) (Eltayeb et al., 2007). Herein, we report the crystal structure of (I).
In (I), the Zn1 and O1W atoms lie on a mirror plane and the asymmetric unit therefore contains only half of the molecule. The tetradentate Schiff-base ligand is almost planar with a maximum deviation from the C1–C10/O1–O2/N1 plane of 0.053 (3) Å for atom N1. The methoxy group is slightly twisted from the C1–C10/O1–O2/N1 mean plane as indicated by the torsion angle C11/O2/C4/C5 of -9.6 (2)°. The ligand is coordinated to Zn1 as a tetradentate ligand via through two N and two O donor atoms, resulting in a square-pyramidal ZnII center whose fifth (axial) position is occupied by a water molecule (Fig. 1). The four atoms N1, O1, N1i and O1i [i = -x, y, z] form the basal plane, and the ZnII is displaced 0.044 (7) Å out of this mean basal plane towards the axial water molecule. Bond lengths and angles observed in the structure are normal (Allen et al., 1987).
In the crystal of (I) in Fig. 2, the water molecule is involved in an intermolecular O—H···O hydrogen bond [O1W—H1W···O1; symmetry code x, -1 + y, +z] and the ligand is involved in weak C—H···O intermolecular interaction [C7—H7A···O2; symmetry code 1/2 - x, -y, -1/2 + z] (Table 2). The molcecules are linked into chains along the b axis. These chains are further interconnected in a zig-zag manner into a three-dimensional network.