metal-organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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Bis{2-[(1H-pyrrol-2-yl)methyl­imino­meth­yl]phenolato-κ2N,O}zinc(II)

aEngineering Research Center for Clean Production of Textile Dyeing and Printing, Ministry of Education, Wuhan 430073, People's Republic of China
*Correspondence e-mail: qiangqiang_wang@163.com

(Received 19 August 2009; accepted 26 August 2009; online 29 August 2009)

In the title compound, [Zn(C12H11N2O)2], the ZnII atom, lying on an inversion center, is coordinated by two O atoms and two N atoms from two salicylal Schiff base ligands in a distorted square-planar geometry. A three-dimensional network is formed by inter­molecular C—H⋯N hydrogen bonds and C—H⋯π contacts.

Related literature

For general background to Schiff base complexes, see: Qiu et al. (2006[Qiu, X.-Y., Liu, W.-S., Hao, F.-Y. & Zhu, H.-L. (2006). Synth. React. Inorg. Met. 36, 595-597.]); Shi et al. (2007[Shi, D.-H., You, Z.-L., Xu, C., Zhang, Q. & Zhu, H.-L. (2007). Inorg. Chem. Commun. 10, 404-406.]); Xiao et al. (2007a[Xiao, Z.-P., Fang, R.-Q., Shi, L., Ding, H., Xu, C. & Zhu, H.-L. (2007a). Can. J. Chem. 85, 951-957.],b[Xiao, Z.-P., Shi, D.-H., Li, H.-Q., Zhang, L.-N., Xu, C. & Zhu, H.-L. (2007b). Bioorg. Med. Chem. 15, 3703-3710.], 2008[Xiao, Z.-P., Li, H.-Q., Xue, J.-Y., Shi, L. & Zhu, H.-L. (2008). Synth. Commun. 38, 525-529.]); You et al. (2006[You, Z.-L., Shi, D.-H. & Zhu, H.-L. (2006). Inorg. Chem. Commun. 9, 642-644.]). For related structures, see: Qiu et al. (2004[Qiu, X.-Y., Liu, Q.-X., Wang, Z.-G., Lin, Y.-S., Zeng, W.-J., Fun, H.-K. & Zhu, H.-L. (2004). Z. Kristallogr. New Cryst. Struct. 219, 150-152.]); You et al. (2004[You, Z.-L., Zhu, H.-L. & Liu, W.-S. (2004). Acta Cryst. E60, m560-m562.]).

[Scheme 1]

Experimental

Crystal data
  • [Zn(C12H11N2O)2]

  • Mr = 463.83

  • Triclinic, [P \overline 1]

  • a = 5.3443 (4) Å

  • b = 9.8669 (8) Å

  • c = 10.1392 (8) Å

  • α = 104.108 (1)°

  • β = 95.830 (1)°

  • γ = 100.126 (1)°

  • V = 504.58 (7) Å3

  • Z = 1

  • Mo Kα radiation

  • μ = 1.25 mm−1

  • T = 200 K

  • 0.30 × 0.30 × 0.20 mm

Data collection
  • Bruker SMART APEX CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS. University of Göttingen, Germany.]) Tmin = 0.706, Tmax = 0.789

  • 6063 measured reflections

  • 2455 independent reflections

  • 2432 reflections with I > 2σ(I)

  • Rint = 0.047

Refinement
  • R[F2 > 2σ(F2)] = 0.050

  • wR(F2) = 0.144

  • S = 1.11

  • 2455 reflections

  • 142 parameters

  • H-atom parameters constrained

  • Δρmax = 1.07 e Å−3

  • Δρmin = −0.73 e Å−3

Table 1
Selected bond lengths (Å)

Zn1—O1 1.8967 (19)
Zn1—N1 2.001 (2)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H8A⋯O1i 0.99 2.26 2.770 (3) 111
C7—H7⋯N2ii 0.95 2.51 3.453 (3) 170
C6—H6⋯Cg1iii 0.95 2.73 3.624 (3) 158
C11—H11⋯Cg2iv 0.95 2.81 3.615 (3) 143
Symmetry codes: (i) -x+1, -y+2, -z+1; (ii) -x+1, -y+1, -z+1; (iii) -x+2, -y+2, -z+1; (iv) x, y, z+1. Cg1 and Cg2 are the centroids of the N2,C9–C12 and C1–C6 rings, respectively.

Data collection: SMART (Bruker, 2007[Bruker (2007). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). SMART and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXTL.

Supporting information


Comment top

In preparing metal complexes, Schiff base ligands have been frequently employed (Qiu et al., 2004, 2006; Shi et al., 2007; Xiao et al., 2007a,b; Xiao et al., 2008; You et al., 2006). Zinc derivatives are particularly interesting owing to their essential importance in several biological processes (You et al., 2004, 2006; Xiao et al., 2007a,b; Xiao et al., 2008). We have reported the structures of a few zinc(II) complexes (You et al., 2004; Qiu et al., 2004). As an extension of our work, we report here the structure of a zinc(II) complex with salicylal Schiff base ligands.

The title compound consists of a ZnII atom, lying on an inversion center, and two bidentate salicylal Schiff base ligands. The central ZnII atom is coordinated by two N atoms from the pyrrole groups and two O atoms from the phenolate groups, forming a slightly distorted square-planar geometry (Fig. 1). The distortion arises from the difference between Zn—O and Zn—N bonds (Table 1). The six-membered ring (Zn1, N1, C7, C2, C1, O1) and the benzene ring are almost co-planar with a mean deviation of 0.046 (1) Å.

Intramolecular C—H···O hydrogen bond occours between H8A and O1 (Fig. 1 and Table 2). C—H···π contacts involving C6—H6···Cg1iii [Cg1 is the centroid of N2, C9–C12 ring; symmetry code: (iii) 2-x, 2-y, 1-z] and C11—H11···Cg2iv [Cg2 is the centroid of C1–C6 ring; (iv) x, y, 1+z] are observed (Fig. 3). These interactions as well as intermolecular C—H···N hydrogen bond (Fig. 2) connect the molecules into a three-dimensional network.

Related literature top

For general background to Schiff base complexes, see: Qiu et al. (2006); Shi et al. (2007); Xiao et al. (2007a,b, 2008); You et al. (2006). For related structures, see: Qiu et al. (2004); You et al. (2004). Cg1 and Cg2 are the centroids of the N2,C9–C12 and C1–C6 rings, respectively.

Experimental top

Zinc oxide (0.5 mmol), salicylaldehyde (1 mmol) and (1H-pyrrol-yl)methanamine (1 mmol) were dissolved in 10 ml of methanol. After 3 ml ammonia was added, the resulting solution was heated to 423 K for 10 h. The reactor was cooled to room temperature at a rate of 10 K h-1. The mixture was filtered and held at room temperature for 10 d. Colorless block crystals were isolated (yield 38%).

Refinement top

H atoms were positioned geometrically and refined as riding atoms, with C—H = 0.95 (CH), 0.99 (CH2) Å and N—H = 0.88 Å, and with Uiso(H) = 1.2Ueq(C,N).

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound. Displacement ellipsoids are drawn at the 30% probability level. Dashed lines indicate hydrogen bonds. [Symmetry code: (i) 1-x, 2-y, 1-z.]
[Figure 2] Fig. 2. Packing diagram of the title compound. Dashed lines indicate C—H···N hydrogen bonds.
[Figure 3] Fig. 3. C—H···π interactions in the title compound (dashed lines).
Bis{2-[(1H-pyrrol-2-yl)methyliminomethyl]phenolato- κ2N,O}zinc(II) top
Crystal data top
[Zn(C12H11N2O)2]Z = 1
Mr = 463.83F(000) = 240
Triclinic, P1Dx = 1.526 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 5.3443 (4) ÅCell parameters from 2361 reflections
b = 9.8669 (8) Åθ = 2.7–26.6°
c = 10.1392 (8) ŵ = 1.25 mm1
α = 104.108 (1)°T = 200 K
β = 95.830 (1)°Block, colorless
γ = 100.126 (1)°0.30 × 0.30 × 0.20 mm
V = 504.58 (7) Å3
Data collection top
Bruker SMART APEX CCD
diffractometer
2455 independent reflections
Radiation source: fine-focus sealed tube2432 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.047
ϕ and ω scansθmax = 28.3°, θmin = 2.2°
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
h = 77
Tmin = 0.706, Tmax = 0.789k = 1313
6063 measured reflectionsl = 1313
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.050Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.144H-atom parameters constrained
S = 1.11 w = 1/[σ2(Fo2) + (0.0948P)2 + 0.2435P]
where P = (Fo2 + 2Fc2)/3
2455 reflections(Δ/σ)max < 0.001
142 parametersΔρmax = 1.07 e Å3
0 restraintsΔρmin = 0.73 e Å3
Crystal data top
[Zn(C12H11N2O)2]γ = 100.126 (1)°
Mr = 463.83V = 504.58 (7) Å3
Triclinic, P1Z = 1
a = 5.3443 (4) ÅMo Kα radiation
b = 9.8669 (8) ŵ = 1.25 mm1
c = 10.1392 (8) ÅT = 200 K
α = 104.108 (1)°0.30 × 0.30 × 0.20 mm
β = 95.830 (1)°
Data collection top
Bruker SMART APEX CCD
diffractometer
2455 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
2432 reflections with I > 2σ(I)
Tmin = 0.706, Tmax = 0.789Rint = 0.047
6063 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0500 restraints
wR(F2) = 0.144H-atom parameters constrained
S = 1.11Δρmax = 1.07 e Å3
2455 reflectionsΔρmin = 0.73 e Å3
142 parameters
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
C10.8616 (5)0.9132 (3)0.3153 (2)0.0297 (5)
C20.7761 (5)0.7658 (3)0.3046 (2)0.0306 (5)
C30.8882 (6)0.6636 (3)0.2175 (3)0.0379 (6)
H30.82950.56480.20880.045*
C41.0792 (6)0.7055 (3)0.1461 (3)0.0392 (6)
H41.15180.63670.08800.047*
C51.1647 (6)0.8508 (4)0.1602 (3)0.0403 (6)
H51.29840.88040.11200.048*
C61.0611 (5)0.9518 (3)0.2417 (3)0.0363 (5)
H61.12461.05000.24910.044*
C70.5899 (5)0.7143 (3)0.3816 (3)0.0320 (5)
H70.54920.61390.36880.038*
C80.2983 (5)0.7075 (3)0.5401 (3)0.0331 (5)
H8A0.14030.74640.54830.040*
H8B0.24780.60610.48660.040*
C90.4297 (5)0.7175 (3)0.6791 (3)0.0290 (5)
C100.3985 (5)0.7807 (4)0.8078 (3)0.0398 (6)
H100.27240.83490.83360.048*
C110.5913 (6)0.7507 (4)0.8987 (3)0.0447 (7)
H110.61850.78110.99640.054*
C120.7259 (6)0.6713 (3)0.8190 (3)0.0405 (6)
H120.86650.63540.85190.049*
N10.4708 (4)0.7890 (2)0.4666 (2)0.0297 (4)
N20.6319 (4)0.6496 (2)0.6837 (2)0.0291 (4)
H2A0.69010.60110.61270.035*
O10.7656 (4)1.0126 (2)0.3902 (2)0.0346 (4)
Zn10.50001.00000.50000.02730 (17)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0298 (11)0.0310 (11)0.0267 (10)0.0055 (9)0.0013 (8)0.0079 (9)
C20.0311 (11)0.0325 (12)0.0263 (10)0.0053 (9)0.0014 (8)0.0075 (9)
C30.0413 (14)0.0378 (13)0.0334 (12)0.0112 (11)0.0002 (10)0.0074 (10)
C40.0384 (14)0.0478 (15)0.0307 (12)0.0177 (11)0.0042 (10)0.0035 (11)
C50.0349 (13)0.0527 (17)0.0340 (13)0.0124 (11)0.0044 (10)0.0110 (12)
C60.0331 (12)0.0405 (13)0.0353 (12)0.0057 (10)0.0047 (9)0.0118 (10)
C70.0370 (12)0.0265 (11)0.0300 (11)0.0048 (9)0.0000 (9)0.0062 (9)
C80.0350 (12)0.0292 (11)0.0318 (11)0.0022 (9)0.0009 (9)0.0108 (9)
C90.0282 (11)0.0285 (11)0.0320 (11)0.0050 (8)0.0041 (8)0.0123 (9)
C100.0311 (12)0.0613 (18)0.0306 (12)0.0152 (12)0.0082 (9)0.0140 (12)
C110.0368 (14)0.069 (2)0.0317 (13)0.0110 (13)0.0041 (10)0.0206 (13)
C120.0392 (14)0.0448 (15)0.0402 (14)0.0106 (11)0.0011 (11)0.0182 (12)
N10.0334 (10)0.0272 (9)0.0269 (9)0.0031 (7)0.0000 (7)0.0085 (7)
N20.0327 (10)0.0275 (9)0.0292 (9)0.0129 (8)0.0035 (7)0.0074 (7)
O10.0368 (9)0.0299 (9)0.0384 (9)0.0067 (7)0.0114 (7)0.0096 (7)
Zn10.0300 (2)0.0258 (2)0.0259 (2)0.00531 (15)0.00390 (14)0.00714 (15)
Geometric parameters (Å, º) top
C1—O11.302 (3)C8—N11.491 (3)
C1—C61.413 (4)C8—H8A0.9900
C1—C21.419 (4)C8—H8B0.9900
C2—C71.425 (4)C9—C101.344 (4)
C2—C31.429 (4)C9—N21.371 (3)
C3—C41.373 (4)C10—C111.430 (4)
C3—H30.9500C10—H100.9500
C4—C51.393 (5)C11—C121.339 (5)
C4—H40.9500C11—H110.9500
C5—C61.367 (4)C12—N21.363 (3)
C5—H50.9500C12—H120.9500
C6—H60.9500N2—H2A0.8800
C7—N11.287 (3)Zn1—O11.8967 (19)
C7—H70.9500Zn1—N12.001 (2)
C8—C91.481 (3)
O1—C1—C6119.4 (2)H8A—C8—H8B108.1
O1—C1—C2122.8 (2)C10—C9—N2109.4 (2)
C6—C1—C2117.8 (3)C10—C9—C8134.5 (2)
C1—C2—C7123.0 (2)N2—C9—C8116.1 (2)
C1—C2—C3119.1 (2)C9—C10—C11106.9 (3)
C7—C2—C3117.8 (2)C9—C10—H10126.6
C4—C3—C2121.3 (3)C11—C10—H10126.6
C4—C3—H3119.4C12—C11—C10106.5 (3)
C2—C3—H3119.4C12—C11—H11126.8
C3—C4—C5118.8 (3)C10—C11—H11126.8
C3—C4—H4120.6C11—C12—N2110.1 (2)
C5—C4—H4120.6C11—C12—H12124.9
C6—C5—C4121.7 (3)N2—C12—H12124.9
C6—C5—H5119.2C7—N1—C8115.6 (2)
C4—C5—H5119.2C7—N1—Zn1124.25 (18)
C5—C6—C1121.3 (3)C8—N1—Zn1120.09 (17)
C5—C6—H6119.3C12—N2—C9107.1 (2)
C1—C6—H6119.3C12—N2—H2A126.4
N1—C7—C2127.1 (2)C9—N2—H2A126.4
N1—C7—H7116.4C1—O1—Zn1130.68 (18)
C2—C7—H7116.4O1i—Zn1—O1180.000 (1)
C9—C8—N1110.58 (19)O1i—Zn1—N188.44 (9)
C9—C8—H8A109.5O1—Zn1—N191.56 (9)
N1—C8—H8A109.5O1i—Zn1—N1i91.56 (9)
C9—C8—H8B109.5O1—Zn1—N1i88.44 (9)
N1—C8—H8B109.5N1—Zn1—N1i180.00 (12)
O1—C1—C2—C74.2 (4)C9—C10—C11—C120.1 (4)
C6—C1—C2—C7175.2 (2)C10—C11—C12—N20.3 (4)
O1—C1—C2—C3178.6 (2)C2—C7—N1—C8176.0 (2)
C6—C1—C2—C32.0 (3)C2—C7—N1—Zn15.3 (4)
C1—C2—C3—C41.1 (4)C9—C8—N1—C798.0 (3)
C7—C2—C3—C4176.3 (2)C9—C8—N1—Zn183.2 (2)
C2—C3—C4—C50.4 (4)C11—C12—N2—C90.4 (3)
C3—C4—C5—C60.8 (4)C10—C9—N2—C120.3 (3)
C4—C5—C6—C10.1 (4)C8—C9—N2—C12179.9 (2)
O1—C1—C6—C5179.0 (2)C6—C1—O1—Zn1179.70 (17)
C2—C1—C6—C51.6 (4)C2—C1—O1—Zn10.9 (4)
C1—C2—C7—N11.6 (4)C1—O1—Zn1—N15.4 (2)
C3—C2—C7—N1178.9 (2)C1—O1—Zn1—N1i174.6 (2)
N1—C8—C9—C10111.4 (3)C7—N1—Zn1—O1i172.7 (2)
N1—C8—C9—N268.1 (3)C8—N1—Zn1—O1i5.97 (17)
N2—C9—C10—C110.1 (3)C7—N1—Zn1—O17.3 (2)
C8—C9—C10—C11179.6 (3)C8—N1—Zn1—O1174.03 (17)
Symmetry code: (i) x+1, y+2, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8A···O1i0.992.262.770 (3)111
C7—H7···N2ii0.952.513.453 (3)170
C6—H6···Cg1iii0.952.733.624 (3)158
C11—H11···Cg2iv0.952.813.615 (3)143
Symmetry codes: (i) x+1, y+2, z+1; (ii) x+1, y+1, z+1; (iii) x+2, y+2, z+1; (iv) x, y, z+1.

Experimental details

Crystal data
Chemical formula[Zn(C12H11N2O)2]
Mr463.83
Crystal system, space groupTriclinic, P1
Temperature (K)200
a, b, c (Å)5.3443 (4), 9.8669 (8), 10.1392 (8)
α, β, γ (°)104.108 (1), 95.830 (1), 100.126 (1)
V3)504.58 (7)
Z1
Radiation typeMo Kα
µ (mm1)1.25
Crystal size (mm)0.30 × 0.30 × 0.20
Data collection
DiffractometerBruker SMART APEX CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.706, 0.789
No. of measured, independent and
observed [I > 2σ(I)] reflections
6063, 2455, 2432
Rint0.047
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.050, 0.144, 1.11
No. of reflections2455
No. of parameters142
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)1.07, 0.73

Computer programs: SMART (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Selected bond lengths (Å) top
Zn1—O11.8967 (19)Zn1—N12.001 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8A···O1i0.992.262.770 (3)111
C7—H7···N2ii0.952.513.453 (3)170
C6—H6···Cg1iii0.952.733.624 (3)158
C11—H11···Cg2iv0.952.813.615 (3)143
Symmetry codes: (i) x+1, y+2, z+1; (ii) x+1, y+1, z+1; (iii) x+2, y+2, z+1; (iv) x, y, z+1.
 

References

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