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

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Di­chlorido(2,9-dieth­­oxy-1,10-phenanthroline-κ2N,N′)zinc(II)

aCollege of Sciences, Henan Agricultural University, Zhengzhou 450002, People's Republic of China
*Correspondence e-mail: niu_cy2000@yahoo.com.cn

(Received 13 June 2009; accepted 25 June 2009; online 1 July 2009)

All non-H atoms except for the Cl atoms lie on a mirror plane in the title complex, [ZnCl2(C16H16N2O2)]. The ZnII ion is coordinated by two N atoms from a bis-chelating 2,9-dieth­oxy-1,10-phenanthroline ligand and two symmetry-related Cl atoms in a distorted tetra­hedral environment. The two Zn—N bond lengths are significantly different from each other and the N—Zn—N angle is acute. In the crystal structure, there are weak but significant ππ stacking inter­actions between phenanthroline rings, with a centroid–centroid distance of 3.764 (1) Å.

Related literature

For background information, see: Majumder et al. (2006[Majumder, A., Westerhausen, M., Kneifel, A. N., Sutter, J.-P., Daro, N. & Mitra, S. (2006). Inorg. Chim. Acta, 359, 3841-3846.]); Bie et al. (2006[Bie, H. Y., Wei, J., Yu, J. H., Wang, T. G., Lu, J. & Xu, J. Q. (2006). Mater. Lett. 60, 2475-2479.]). For synthetic details, see: Pijper et al. (1984[Pijper, P. L., Van der Goot, H., Timmerman, H. & Nauta, W. T. (1984). Eur. J. Med. Chem. 19, 399-404.]).

[Scheme 1]

Experimental

Crystal data
  • [ZnCl2(C16H16N2O2)]

  • Mr = 404.58

  • Orthorhombic, P n m a

  • a = 13.255 (3) Å

  • b = 7.4403 (15) Å

  • c = 17.874 (4) Å

  • V = 1762.7 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 1.71 mm−1

  • T = 291 K

  • 0.20 × 0.18 × 0.17 mm

Data collection
  • Bruker APEX-II CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 1996[Sheldrick, G. M. (1996). SADABS . University of Göttingen, Germany.]) Tmin = 0.727, Tmax = 0.760

  • 5148 measured reflections

  • 1741 independent reflections

  • 1303 reflections with I > 2σ(I)

  • Rint = 0.052

Refinement
  • R[F2 > 2σ(F2)] = 0.048

  • wR(F2) = 0.089

  • S = 1.08

  • 1741 reflections

  • 136 parameters

  • H-atom parameters constrained

  • Δρmax = 0.34 e Å−3

  • Δρmin = −0.58 e Å−3

Table 1
Selected geometric parameters (Å, °)

Zn1—N1 2.065 (3)
Zn1—N2 2.118 (4)
Zn1—Cl1 2.2022 (10)
Zn1—Cl1i 2.2022 (10)
N1—Zn1—N2 79.43 (13)
N1—Zn1—Cl1 112.53 (5)
N2—Zn1—Cl1 112.90 (4)
N1—Zn1—Cl1i 112.53 (5)
N2—Zn1—Cl1i 112.90 (4)
Cl1—Zn1—Cl1i 119.74 (6)
Symmetry code: (i) [x, -y+{\script{1\over 2}}, z].

Data collection: SMART (Siemens, 1996[Siemens (1996). SMART. Siemens Analytical X-ray Instruments Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Siemens, 1994[Siemens (1994). SAINT. Siemens Analytical X-ray Instruments 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: SHELXL97 and DIAMOND (Brandenburg, 2005[Brandenburg, K. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The compound 1,10-phenanthroline has been reported as used to synthesize some potential strong luminescent materials with d10 metals. It was predicted that the title compound which is composed of a derivative of 1,10-phenanthroline and a d10 metal would possess strong ligand to ligand or metal perturbed ligand to ligand emissions (Majumder et al., 2006; Bie, et al., 2006). The ligand 2,9-Diethoxy-1,10-phenanthroline as a derivative of 1,10-phenanthroline was synthesized at an earlier time and possesses antimycoplasmal activity in the presence of copper (Pijper, et al., 1984).

The title mononuclear zinc(II) complex is shown in Fig. 1. All non-hydrogen atoms, execpt for the Cl atoms, lie on a mirror plane. The ZnII ion is four coordinated by two nitrogen atoms from the 1,10-phenanthroline ring system (N1 and N2) and two chlorine atoms [Cl1, Cl1i. Symmetry code: (i) x, -y + 1/2, z], defining a disotorted tetrahedral coordination environment. In the crystal structure there are weak but significant ππ stacking interactions between phenanthroline rings (Fig. 2) with a centroid-to-centroid distance of 3.764 (1) Å.

Related literature top

For background information, see: Majumder et al. (2006); Bie et al. (2006). For synthetic details, see: Pijper et al. (1984).

Experimental top

The organic ligand 2,9-diethoxy-1,10-phenanthroline was prepared according to the procedure of literature (Pijper, et al., 1984). The slow evaporation of mixture of the ligand (0.024 g, 0.1 mmol) and zinc dichloride (0.014 g, 0.1 mmol) in 30 ml me thanol afforded suitable colourless block crystals in about 7 days (yield 60%).

Refinement top

Carbon-bound H atoms were positioned geometrically and refined using a riding model [C—H = 0.93 Å and Uiso(H) = 1.2 Ueq(C) for aromatic H atoms; C—H = 0.97 Å and Uiso(H) = 1.2 Ueq(C) for methylene H atoms; C—H = 0.96 Å and Uiso(H) = 1.5 Ueq(C) for methyl H atoms;]. The final difference Fourier map had a highest peak at 1.17 Å from atom Zn1 and a deepest hole at 1.04 Å from atom Zn1.

Computing details top

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1994); data reduction: SAINT (Siemens, 1994); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXL97 (Sheldrick, 2008) and DIAMOND (Brandenburg, 2005); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title complex, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii. [Symmetry codes: (i) x, -y + 1/2, z.]
[Figure 2] Fig. 2. Part of the crystal structure showing a ππ interaction (purple dotted line). All H atoms have been omitted for clarity.
Dichlorido(2,9-diethoxy-1,10-phenanthroline-κ2N,N')zinc(II) top
Crystal data top
[ZnCl2(C16H16N2O2)]F(000) = 824
Mr = 404.58Dx = 1.524 Mg m3
Orthorhombic, PnmaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2nCell parameters from 398 reflections
a = 13.255 (3) Åθ = 2–25.1°
b = 7.4403 (15) ŵ = 1.71 mm1
c = 17.874 (4) ÅT = 291 K
V = 1762.7 (6) Å3Prismatic, colorless
Z = 40.20 × 0.18 × 0.17 mm
Data collection top
Bruker APEX-II CCD detector
diffractometer
1741 independent reflections
Radiation source: fine-focus sealed tube1303 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.052
Detector resolution: 0 pixels mm-1θmax = 25.5°, θmin = 1.9°
Oscillation frames scansh = 160
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
k = 88
Tmin = 0.727, Tmax = 0.760l = 2121
5148 measured reflections
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)] = 0.048Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.089H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.042P)2]
where P = (Fo2 + 2Fc2)/3
1741 reflections(Δ/σ)max < 0.001
136 parametersΔρmax = 0.34 e Å3
0 restraintsΔρmin = 0.58 e Å3
Crystal data top
[ZnCl2(C16H16N2O2)]V = 1762.7 (6) Å3
Mr = 404.58Z = 4
Orthorhombic, PnmaMo Kα radiation
a = 13.255 (3) ŵ = 1.71 mm1
b = 7.4403 (15) ÅT = 291 K
c = 17.874 (4) Å0.20 × 0.18 × 0.17 mm
Data collection top
Bruker APEX-II CCD detector
diffractometer
1741 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 1996)
1303 reflections with I > 2σ(I)
Tmin = 0.727, Tmax = 0.760Rint = 0.052
5148 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0480 restraints
wR(F2) = 0.089H-atom parameters constrained
S = 1.08Δρmax = 0.34 e Å3
1741 reflectionsΔρmin = 0.58 e Å3
136 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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/UeqOcc. (<1)
Zn10.76441 (4)0.25000.40645 (3)0.03224 (18)
Cl10.72431 (7)0.00599 (12)0.35222 (5)0.0513 (3)
O10.9753 (2)0.25000.33493 (19)0.0549 (10)
O20.5679 (2)0.25000.51182 (18)0.0441 (9)
N10.9098 (2)0.25000.4479 (2)0.0326 (9)
N20.7355 (2)0.25000.5230 (2)0.0330 (9)
C10.9938 (3)0.25000.4084 (3)0.0409 (12)
C21.0897 (3)0.25000.4426 (3)0.0464 (14)
H2A1.14800.25000.41360.056*
C31.0957 (4)0.25000.5183 (3)0.0512 (15)
H3A1.15850.25000.54150.061*
C41.0068 (4)0.25000.5625 (3)0.0425 (13)
C50.9155 (3)0.25000.5242 (3)0.0325 (11)
C60.8217 (3)0.25000.5640 (3)0.0327 (11)
C70.8228 (4)0.25000.6423 (3)0.0411 (12)
C80.7279 (4)0.25000.6775 (3)0.0530 (14)
H8A0.72440.25000.72950.064*
C90.6412 (4)0.25000.6367 (3)0.0489 (15)
H9A0.57870.25000.66040.059*
C100.6474 (3)0.25000.5576 (3)0.0382 (13)
C111.0056 (4)0.25000.6427 (3)0.0576 (16)
H11A1.06630.25000.66890.069*
C120.9174 (4)0.25000.6808 (3)0.0537 (15)
H12A0.91830.25000.73290.064*
C131.0535 (4)0.25000.2795 (3)0.0527 (15)
H13A1.09560.35610.28430.063*0.50
H13B1.09560.14390.28430.063*0.50
C140.9988 (4)0.25000.2065 (3)0.081 (2)
H14A1.04680.25000.16630.122*
H14B0.95720.14460.20320.122*0.50
H14C0.95720.35540.20320.122*0.50
C150.4675 (3)0.25000.5431 (3)0.0578 (17)
H15A0.45760.14420.57400.069*0.50
H15B0.45760.35580.57400.069*0.50
C160.3943 (4)0.25000.4794 (3)0.0608 (17)
H16A0.32660.25000.49870.091*
H16B0.40460.35540.44940.091*0.50
H16C0.40460.14460.44940.091*0.50
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Zn10.0278 (3)0.0404 (3)0.0285 (3)0.0000.0007 (2)0.000
Cl10.0576 (6)0.0440 (6)0.0523 (6)0.0023 (5)0.0032 (5)0.0099 (5)
O10.0288 (18)0.102 (3)0.034 (2)0.0000.0083 (16)0.000
O20.0246 (17)0.070 (3)0.038 (2)0.0000.0068 (15)0.000
N10.024 (2)0.042 (3)0.031 (2)0.0000.0012 (17)0.000
N20.030 (2)0.040 (2)0.029 (2)0.0000.0015 (19)0.000
C10.030 (2)0.045 (3)0.048 (3)0.0000.000 (3)0.000
C20.023 (2)0.064 (4)0.052 (4)0.0000.006 (2)0.000
C30.030 (3)0.058 (4)0.065 (4)0.0000.013 (3)0.000
C40.036 (3)0.047 (3)0.044 (3)0.0000.009 (2)0.000
C50.030 (2)0.030 (3)0.037 (3)0.0000.008 (2)0.000
C60.034 (3)0.035 (3)0.029 (3)0.0000.005 (2)0.000
C70.052 (3)0.044 (3)0.027 (3)0.0000.002 (2)0.000
C80.062 (4)0.072 (4)0.025 (3)0.0000.009 (3)0.000
C90.040 (3)0.072 (4)0.034 (3)0.0000.009 (3)0.000
C100.033 (3)0.049 (4)0.033 (3)0.0000.006 (2)0.000
C110.048 (3)0.076 (5)0.048 (4)0.0000.025 (3)0.000
C120.054 (3)0.077 (5)0.029 (3)0.0000.008 (3)0.000
C130.038 (3)0.069 (4)0.050 (4)0.0000.017 (3)0.000
C140.051 (4)0.149 (7)0.044 (4)0.0000.013 (3)0.000
C150.030 (3)0.096 (5)0.047 (4)0.0000.011 (3)0.000
C160.034 (3)0.093 (5)0.056 (4)0.0000.003 (3)0.000
Geometric parameters (Å, º) top
Zn1—N12.065 (3)C7—C81.406 (7)
Zn1—N22.118 (4)C7—C121.431 (7)
Zn1—Cl12.2022 (10)C8—C91.362 (7)
Zn1—Cl1i2.2022 (10)C8—H8A0.9300
O1—C11.336 (6)C9—C101.415 (6)
O1—C131.434 (5)C9—H9A0.9300
O2—C101.335 (5)C11—C121.353 (7)
O2—C151.443 (5)C11—H11A0.9300
N1—C11.318 (5)C12—H12A0.9300
N1—C51.366 (6)C13—C141.493 (7)
N2—C101.322 (5)C13—H13A0.9700
N2—C61.358 (5)C13—H13B0.9700
C1—C21.410 (6)C14—H14A0.9600
C2—C31.356 (7)C14—H14B0.9600
C2—H2A0.9300C14—H14C0.9600
C3—C41.418 (7)C15—C161.496 (7)
C3—H3A0.9300C15—H15A0.9700
C4—C51.390 (6)C15—H15B0.9700
C4—C111.434 (7)C16—H16A0.9600
C5—C61.433 (6)C16—H16B0.9600
C6—C71.400 (6)C16—H16C0.9600
N1—Zn1—N279.43 (13)C7—C8—H8A119.5
N1—Zn1—Cl1112.53 (5)C8—C9—C10119.1 (5)
N2—Zn1—Cl1112.90 (4)C8—C9—H9A120.5
N1—Zn1—Cl1i112.53 (5)C10—C9—H9A120.5
N2—Zn1—Cl1i112.90 (4)N2—C10—O2114.2 (4)
Cl1—Zn1—Cl1i119.74 (6)N2—C10—C9121.3 (4)
C1—O1—C13123.1 (4)O2—C10—C9124.5 (4)
C10—O2—C15119.3 (4)C12—C11—C4120.8 (5)
C1—N1—C5119.2 (4)C12—C11—H11A119.6
C1—N1—Zn1126.6 (3)C4—C11—H11A119.6
C5—N1—Zn1114.2 (3)C11—C12—C7121.0 (5)
C10—N2—C6119.4 (4)C11—C12—H12A119.5
C10—N2—Zn1128.4 (3)C7—C12—H12A119.5
C6—N2—Zn1112.3 (3)O1—C13—C14104.6 (4)
N1—C1—O1111.8 (4)O1—C13—H13A110.8
N1—C1—C2122.0 (5)C14—C13—H13A110.8
O1—C1—C2126.3 (4)O1—C13—H13B110.8
C3—C2—C1119.0 (5)C14—C13—H13B110.8
C3—C2—H2A120.5H13A—C13—H13B108.9
C1—C2—H2A120.5C13—C14—H14A109.5
C2—C3—C4120.5 (5)C13—C14—H14B109.5
C2—C3—H3A119.7H14A—C14—H14B109.5
C4—C3—H3A119.7C13—C14—H14C109.5
C5—C4—C3116.6 (5)H14A—C14—H14C109.5
C5—C4—C11118.9 (5)H14B—C14—H14C109.5
C3—C4—C11124.5 (5)O2—C15—C16107.6 (4)
N1—C5—C4122.7 (4)O2—C15—H15A110.2
N1—C5—C6116.6 (4)C16—C15—H15A110.2
C4—C5—C6120.7 (5)O2—C15—H15B110.2
N2—C6—C7123.3 (4)C16—C15—H15B110.2
N2—C6—C5117.5 (4)H15A—C15—H15B108.5
C7—C6—C5119.2 (4)C15—C16—H16A109.5
C6—C7—C8116.0 (4)C15—C16—H16B109.5
C6—C7—C12119.3 (5)H16A—C16—H16B109.5
C8—C7—C12124.6 (5)C15—C16—H16C109.5
C9—C8—C7121.0 (4)H16A—C16—H16C109.5
C9—C8—H8A119.5H16B—C16—H16C109.5
N2—Zn1—N1—C1180.0C10—N2—C6—C70.000 (1)
Cl1—Zn1—N1—C169.44 (5)Zn1—N2—C6—C7180.0
Cl1i—Zn1—N1—C169.44 (5)C10—N2—C6—C5180.0
N2—Zn1—N1—C50.0Zn1—N2—C6—C50.0
Cl1—Zn1—N1—C5110.56 (5)N1—C5—C6—N20.0
Cl1i—Zn1—N1—C5110.56 (5)C4—C5—C6—N2180.0
N1—Zn1—N2—C10180.0N1—C5—C6—C7180.000 (1)
Cl1—Zn1—N2—C1069.87 (5)C4—C5—C6—C70.000 (1)
Cl1i—Zn1—N2—C1069.87 (5)N2—C6—C7—C80.000 (1)
N1—Zn1—N2—C60.0C5—C6—C7—C8180.000 (1)
Cl1—Zn1—N2—C6110.13 (5)N2—C6—C7—C12180.000 (1)
Cl1i—Zn1—N2—C6110.13 (5)C5—C6—C7—C120.000 (1)
C5—N1—C1—O1180.0C6—C7—C8—C90.000 (1)
Zn1—N1—C1—O10.0C12—C7—C8—C9180.000 (1)
C5—N1—C1—C20.0C7—C8—C9—C100.000 (1)
Zn1—N1—C1—C2180.0C6—N2—C10—O2180.0
C13—O1—C1—N1180.0Zn1—N2—C10—O20.0
C13—O1—C1—C20.0C6—N2—C10—C90.000 (1)
N1—C1—C2—C30.000 (1)Zn1—N2—C10—C9180.0
O1—C1—C2—C3180.0C15—O2—C10—N2180.0
C1—C2—C3—C40.000 (1)C15—O2—C10—C90.000 (1)
C2—C3—C4—C50.000 (1)C8—C9—C10—N20.000 (1)
C2—C3—C4—C11180.000 (1)C8—C9—C10—O2180.000 (1)
C1—N1—C5—C40.000 (1)C5—C4—C11—C120.000 (1)
Zn1—N1—C5—C4180.0C3—C4—C11—C12180.000 (1)
C1—N1—C5—C6180.0C4—C11—C12—C70.000 (2)
Zn1—N1—C5—C60.0C6—C7—C12—C110.000 (2)
C3—C4—C5—N10.0C8—C7—C12—C11180.000 (1)
C11—C4—C5—N1180.0C1—O1—C13—C14180.0
C3—C4—C5—C6180.0C10—O2—C15—C16180.0
C11—C4—C5—C60.000 (1)
Symmetry code: (i) x, y+1/2, z.

Experimental details

Crystal data
Chemical formula[ZnCl2(C16H16N2O2)]
Mr404.58
Crystal system, space groupOrthorhombic, Pnma
Temperature (K)291
a, b, c (Å)13.255 (3), 7.4403 (15), 17.874 (4)
V3)1762.7 (6)
Z4
Radiation typeMo Kα
µ (mm1)1.71
Crystal size (mm)0.20 × 0.18 × 0.17
Data collection
DiffractometerBruker APEX-II CCD detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 1996)
Tmin, Tmax0.727, 0.760
No. of measured, independent and
observed [I > 2σ(I)] reflections
5148, 1741, 1303
Rint0.052
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.048, 0.089, 1.08
No. of reflections1741
No. of parameters136
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.34, 0.58

Computer programs: SMART (Siemens, 1996), SAINT (Siemens, 1994), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and DIAMOND (Brandenburg, 2005).

Selected geometric parameters (Å, º) top
Zn1—N12.065 (3)Zn1—Cl12.2022 (10)
Zn1—N22.118 (4)Zn1—Cl1i2.2022 (10)
N1—Zn1—N279.43 (13)N1—Zn1—Cl1i112.53 (5)
N1—Zn1—Cl1112.53 (5)N2—Zn1—Cl1i112.90 (4)
N2—Zn1—Cl1112.90 (4)Cl1—Zn1—Cl1i119.74 (6)
Symmetry code: (i) x, y+1/2, z.
 

Acknowledgements

We are grateful to Mrs Li for her assistance with the X-ray crystallographic analysis.

References

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