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Acta Cryst. (2009). E65, m15-m16    [ doi:10.1107/S1600536808040269 ]

Bis([mu]-N,N'-di-3-pyridylpyridine-2,6-dicarboxamide)bis[dichloridomercury(II)] N,N-dimethylformamide disolvate

L.-H. Huang and J. Wu

Abstract top

The asymmetric unit of the binuclear title complex, [Hg2Cl4(C17H13N5O2)2]·2C3H7NO, contains one-half of the centrosymmetric molecule and one dimethylformamide solvent molecule. The HgII atom is four-coordinated by two N atoms from two ligands and two Cl atoms in a distorted tetrahedral coordination geometry. Intramolecular N-H...O hydrogen bonds may be effective in the stabilization of the structure. In the crystal structure, [pi]-[pi] contacts between pyridine rings [centroid-to-centroid distances 3.629 (3) and 3.595 (3) Å] may further stabilize the structure.

Comment top

The expansion of the field of metal–organic frameworks (MOFs) of predetermined structure depends on the judicious choice of new linkers and nodes of appropriate coordination algorithms (Ockwig et al., 2005). Rigid polydentate N-donor ligands are typical linkers employed in such a work. N,N'-bis(pyridin-3-yl)-2,6-pyridinedicarboxamide, with a rigid conjugated clamp-like configuration, is a convenient bridging ligand for the syntheses of cyclic complexes (Qin et al., 2003; Baer et al., 2002). In this work, we selected this ligand as linker, to generate the new title coordination complex, and we report herein its crystal structure.

The asymmetric unit of the title compound (Fig. 1) contains one-half molecule and an N,N-dimethylformamide (DMF) molecule, where the bond lengths (Allen et al., 1987) and angles are within normal ranges. The HgII atom is four-coordinated by two N atoms from two ligands and two Cl atoms in a distorted tetrahedral coordination geometry (Table 1). The two HgII atoms are bridged with two N,N'-bis(pyridin-3-yl)-2,6-pyridinedicarboxamide ligands to form a porous MOF with 28-membered macroring. The pyridine rings A (N1/C1–C5), B (N3/C7–C11) and C (N5/C13–C17) are oriented at dihedral angles of A/B = 3.31 (3)°, A/C = 62.29 (3)° and B/C = 60.76 (3)°. The intramolecular N—H···O hydrogen bonds (Table 2, Fig. 1) may be effective in the stabilization of the structure.

In the crystal structure, the π–π contacts between the pyridine rings, Cg1—Cg2i and Cg3—Cg3ii [symmetry codes: (i) 2 - x, 1 - y, -z; (ii) -x, 2 - y, 1 - z, where Cg1, Cg2 and Cg3 are centroids of the rings A (N1/C1–C5), B (N3/C7–C11) and C (N5/C13–C17), respectively] may further stabilize the structure, with centroid–centroid distances of 3.629 (3) Å and 3.595 (3) Å.

Related literature top

For general background, see: Ockwig et al. (2005); Qin et al. (2003); Baer et al. (2002). For bond-length data, see: Allen et al. (1987).

Experimental top

For the preparation of the title compound, the ligand N,N'-bis-(pyridin-3-yl)-2,6-pyridinedicarboxamide (0.016 g, 0.05 mmol) in DMF (5 ml) was added dropwise to a solution of HgCl2 (0.028 g, 0.1 mmol) in methanol (5 ml). The precipitate was filtered and the resulting solution was allowed to stand at room temperature in the dark. After one week high quality colorless crystals were obtained and dried in air.

Computing details top

Data collection: CrystalClear (Rigaku/MSC, 2006); cell refinement: CrystalClear (Rigaku/MSC, 2006); data reduction: CrystalClear (Rigaku/MSC, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2003).

Figures top
[Figure 1] Fig. 1. The asymmetric unit of the title molecule, with the atom-numbering scheme. Hydrogen bonds are shown as dashed lines.
Bis(µ-N,N'-di-3-pyridylpyridine-2,6- dicarboxamide)bis[dichloridomercury(II)] N,N-dimethylformamide disolvate top
Crystal data top
[Hg2Cl4(C17H13N5O2)2]·2C3H7NOZ = 1
Mr = 1327.82F(000) = 640
Triclinic, P1Dx = 1.951 Mg m−3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 7.4947 (15) ÅCell parameters from 3289 reflections
b = 12.262 (3) Åθ = 2.9–26.0°
c = 13.284 (3) ŵ = 7.08 mm−1
α = 79.79 (3)°T = 294 K
β = 73.74 (3)°Prism, colourless
γ = 76.21 (3)°0.20 × 0.18 × 0.17 mm
V = 1130.2 (5) Å3
Data collection top
Rigaku Saturn 724
diffractometer		4422 independent reflections
Radiation source: fine-focus sealed tube3995 reflections with I > 2σ(I)
graphiteRint = 0.030
Detector resolution: 28.5714 pixels mm-1θmax = 26.0°, θmin = 2.9°
dtprofit.ref scansh = −9→9
Absorption correction: numerical
(CrystalClear; Rigaku/MSC, 2006)		k = −15→15
Tmin = 0.332, Tmax = 0.379l = −16→16
12347 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)] = 0.029Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.054H-atom parameters constrained
S = 1.03 w = 1/[σ2(Fo2) + (0.0195P)2 + 0.7349P]
where P = (Fo2 + 2Fc2)/3
4422 reflections(Δ/σ)max = 0.002
291 parametersΔρmax = 0.65 e Å−3
0 restraintsΔρmin = −0.83 e Å−3
Crystal data top
[Hg2Cl4(C17H13N5O2)2]·2C3H7NOγ = 76.21 (3)°
Mr = 1327.82V = 1130.2 (5) Å3
Triclinic, P1Z = 1
a = 7.4947 (15) ÅMo Kα radiation
b = 12.262 (3) ŵ = 7.08 mm−1
c = 13.284 (3) ÅT = 294 K
α = 79.79 (3)°0.20 × 0.18 × 0.17 mm
β = 73.74 (3)°
Data collection top
Rigaku Saturn 724
diffractometer		4422 independent reflections
Absorption correction: numerical
(CrystalClear; Rigaku/MSC, 2006)		3995 reflections with I > 2σ(I)
Tmin = 0.332, Tmax = 0.379Rint = 0.030
12347 measured reflectionsθmax = 26.0°
Refinement top
R[F2 > 2σ(F2)] = 0.029H-atom parameters constrained
wR(F2) = 0.054Δρmax = 0.65 e Å−3
S = 1.03Δρmin = −0.83 e Å−3
4422 reflectionsAbsolute structure: ?
291 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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*/Ueq
Hg10.47943 (3)0.144664 (13)0.675659 (12)0.04821 (7)
Cl10.39934 (16)−0.03890 (9)0.72493 (9)0.0566 (3)
Cl20.26095 (18)0.30392 (9)0.61184 (9)0.0611 (3)
O10.2543 (5)0.4774 (3)1.1235 (2)0.0738 (10)
O2−0.1219 (4)0.9357 (2)0.7985 (2)0.0511 (7)
O30.3641 (4)0.5771 (2)0.7182 (2)0.0546 (8)
N10.4906 (4)0.2103 (2)0.8281 (2)0.0358 (7)
N20.2824 (4)0.4689 (2)0.9507 (2)0.0337 (7)
H2A0.25840.50870.89410.040*
N30.1061 (4)0.6871 (2)0.9285 (2)0.0316 (7)
N40.0775 (4)0.7801 (2)0.7310 (2)0.0352 (7)
H4A0.14520.71510.74590.042*
N50.2361 (4)0.8435 (2)0.4443 (2)0.0387 (7)
N60.6833 (5)0.5377 (3)0.6475 (2)0.0417 (8)
C10.5503 (5)0.1381 (3)0.9066 (3)0.0387 (9)
H70.61180.06450.89440.046*
C20.5222 (5)0.1712 (3)1.0037 (3)0.0401 (9)
H80.56340.11981.05690.048*
C30.4326 (5)0.2808 (3)1.0236 (3)0.0388 (9)
H90.41240.30361.08970.047*
C40.3738 (5)0.3557 (3)0.9418 (3)0.0313 (8)
C50.4047 (5)0.3161 (3)0.8456 (3)0.0323 (8)
H110.36390.36540.79110.039*
C60.2281 (5)0.5222 (3)1.0382 (3)0.0385 (9)
C70.1299 (5)0.6438 (3)1.0247 (3)0.0315 (8)
C80.0694 (5)0.7050 (3)1.1103 (3)0.0419 (9)
H140.08860.67151.17590.050*
C9−0.0202 (5)0.8169 (3)1.0963 (3)0.0432 (9)
H15−0.06010.86071.15190.052*
C10−0.0493 (5)0.8622 (3)0.9980 (3)0.0384 (9)
H16−0.11210.93670.98670.046*
C110.0159 (5)0.7954 (3)0.9168 (3)0.0323 (8)
C12−0.0168 (5)0.8443 (3)0.8101 (3)0.0346 (8)
C130.0691 (5)0.8157 (3)0.6251 (3)0.0324 (8)
C14−0.1022 (5)0.8551 (3)0.5975 (3)0.0397 (9)
H20−0.21650.86040.64880.048*
C15−0.0995 (6)0.8861 (3)0.4925 (3)0.0437 (10)
H21−0.21270.91150.47200.052*
C160.0711 (6)0.8796 (3)0.4179 (3)0.0424 (10)
H220.07130.90100.34710.051*
C170.2348 (5)0.8112 (3)0.5462 (3)0.0341 (8)
H230.35000.78470.56450.041*
C180.8658 (6)0.5671 (4)0.6339 (4)0.0574 (12)
H24A0.91040.59820.56200.086*
H24B0.95520.50050.65040.086*
H24C0.85260.62200.68020.086*
C190.6793 (7)0.4444 (4)0.5953 (4)0.0645 (13)
H25A0.55250.43080.61370.097*
H25B0.76300.37780.61740.097*
H25C0.71960.46290.52020.097*
C200.5254 (6)0.5959 (3)0.7025 (3)0.0470 (10)
H260.53630.65650.73220.056*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Hg10.06800 (12)0.04056 (10)0.03301 (9)−0.01143 (8)−0.00684 (7)−0.00492 (7)
Cl10.0584 (7)0.0423 (6)0.0694 (7)−0.0179 (5)−0.0136 (6)−0.0004 (5)
Cl20.0773 (8)0.0504 (6)0.0618 (7)−0.0063 (6)−0.0364 (6)−0.0009 (5)
O10.125 (3)0.0519 (19)0.0363 (17)0.0185 (19)−0.0330 (18)−0.0114 (14)
O20.0582 (18)0.0368 (15)0.0444 (16)0.0123 (14)−0.0092 (14)−0.0039 (13)
O30.0463 (18)0.0508 (18)0.0482 (17)0.0070 (14)0.0008 (14)−0.0013 (14)
N10.0415 (18)0.0313 (16)0.0329 (16)−0.0063 (14)−0.0069 (14)−0.0047 (13)
N20.0470 (18)0.0270 (15)0.0231 (15)0.0000 (13)−0.0109 (13)0.0006 (12)
N30.0299 (15)0.0311 (16)0.0310 (16)−0.0052 (13)−0.0035 (13)−0.0043 (13)
N40.0411 (18)0.0278 (15)0.0287 (16)0.0016 (13)−0.0053 (13)−0.0002 (13)
N50.050 (2)0.0323 (16)0.0319 (17)−0.0067 (15)−0.0090 (15)−0.0024 (14)
N60.050 (2)0.0349 (17)0.0342 (17)−0.0052 (15)−0.0043 (15)−0.0021 (14)
C10.039 (2)0.0321 (19)0.040 (2)−0.0018 (16)−0.0055 (17)−0.0050 (17)
C20.044 (2)0.036 (2)0.037 (2)−0.0031 (17)−0.0159 (18)0.0055 (17)
C30.050 (2)0.036 (2)0.031 (2)−0.0041 (18)−0.0150 (18)−0.0041 (16)
C40.0338 (19)0.0305 (18)0.0276 (18)−0.0051 (15)−0.0075 (15)−0.0006 (15)
C50.042 (2)0.0294 (18)0.0243 (18)−0.0056 (16)−0.0101 (15)0.0007 (15)
C60.044 (2)0.041 (2)0.029 (2)−0.0039 (18)−0.0095 (17)−0.0072 (17)
C70.0316 (19)0.0341 (19)0.0273 (18)−0.0065 (15)−0.0045 (15)−0.0045 (15)
C80.045 (2)0.051 (2)0.029 (2)−0.0106 (19)−0.0050 (17)−0.0096 (18)
C90.048 (2)0.044 (2)0.037 (2)−0.0104 (19)0.0008 (18)−0.0206 (18)
C100.037 (2)0.034 (2)0.043 (2)−0.0042 (16)−0.0050 (17)−0.0120 (17)
C110.0293 (18)0.0325 (19)0.0319 (19)−0.0071 (15)−0.0004 (15)−0.0063 (16)
C120.033 (2)0.032 (2)0.035 (2)−0.0030 (16)−0.0058 (16)−0.0025 (16)
C130.039 (2)0.0212 (17)0.035 (2)−0.0014 (15)−0.0110 (16)−0.0010 (15)
C140.039 (2)0.0318 (19)0.048 (2)−0.0065 (17)−0.0102 (18)−0.0053 (17)
C150.051 (2)0.0291 (19)0.059 (3)−0.0043 (18)−0.030 (2)−0.0036 (19)
C160.064 (3)0.029 (2)0.040 (2)−0.0092 (19)−0.024 (2)−0.0007 (17)
C170.039 (2)0.0298 (18)0.0311 (19)−0.0017 (16)−0.0099 (16)−0.0016 (15)
C180.058 (3)0.059 (3)0.054 (3)−0.019 (2)−0.013 (2)0.005 (2)
C190.058 (3)0.053 (3)0.074 (3)−0.016 (2)0.010 (2)−0.024 (2)
C200.064 (3)0.036 (2)0.033 (2)0.003 (2)−0.012 (2)−0.0016 (17)
Geometric parameters (Å, °) top
Hg1—N5i2.295 (3)C3—H90.9300
Hg1—N12.337 (3)C4—C51.387 (5)
Hg1—Cl12.3994 (12)C5—H110.9300
Hg1—Cl22.4249 (14)C6—C71.501 (5)
O1—C61.215 (4)C7—C81.383 (5)
O2—C121.219 (4)C8—C91.381 (5)
O3—C201.238 (5)C8—H140.9300
N1—C51.333 (4)C9—C101.381 (5)
N1—C11.348 (5)C9—H150.9300
N2—C61.349 (4)C10—C111.378 (5)
N2—C41.404 (4)C10—H160.9300
N2—H2A0.8600C11—C121.501 (5)
N3—C71.338 (4)C13—C171.379 (5)
N3—C111.343 (4)C13—C141.386 (5)
N4—C121.354 (4)C14—C151.374 (5)
N4—C131.412 (4)C14—H200.9300
N4—H4A0.8600C15—C161.377 (6)
N5—C161.332 (5)C15—H210.9300
N5—C171.340 (4)C16—H220.9300
N5—Hg1i2.295 (3)C17—H230.9300
N6—C201.320 (5)C18—H24A0.9600
N6—C191.449 (5)C18—H24B0.9600
N6—C181.451 (5)C18—H24C0.9600
C1—C21.365 (5)C19—H25A0.9600
C1—H70.9300C19—H25B0.9600
C2—C31.387 (5)C19—H25C0.9600
C2—H80.9300C20—H260.9300
C3—C41.392 (5)
N5i—Hg1—N1106.50 (11)C9—C8—H14120.7
N5i—Hg1—Cl1117.02 (8)C7—C8—H14120.7
N1—Hg1—Cl1108.03 (8)C10—C9—C8118.6 (4)
N5i—Hg1—Cl2103.20 (9)C10—C9—H15120.7
N1—Hg1—Cl299.40 (8)C8—C9—H15120.7
Cl1—Hg1—Cl2120.60 (4)C11—C10—C9119.1 (4)
C5—N1—C1119.2 (3)C11—C10—H16120.5
C5—N1—Hg1118.8 (2)C9—C10—H16120.5
C1—N1—Hg1120.8 (2)N3—C11—C10123.2 (3)
C6—N2—C4127.2 (3)N3—C11—C12117.7 (3)
C6—N2—H2A116.4C10—C11—C12119.1 (3)
C4—N2—H2A116.4O2—C12—N4124.1 (3)
C7—N3—C11117.0 (3)O2—C12—C11120.6 (3)
C12—N4—C13122.6 (3)N4—C12—C11115.3 (3)
C12—N4—H4A118.7C17—C13—C14118.5 (3)
C13—N4—H4A118.7C17—C13—N4119.7 (3)
C16—N5—C17118.8 (3)C14—C13—N4121.8 (3)
C16—N5—Hg1i122.1 (2)C15—C14—C13118.6 (4)
C17—N5—Hg1i118.7 (2)C15—C14—H20120.7
C20—N6—C19120.9 (4)C13—C14—H20120.7
C20—N6—C18121.5 (4)C14—C15—C16119.9 (4)
C19—N6—C18117.6 (3)C14—C15—H21120.1
N1—C1—C2121.1 (3)C16—C15—H21120.1
N1—C1—H7119.4N5—C16—C15121.8 (4)
C2—C1—H7119.4N5—C16—H22119.1
C1—C2—C3120.6 (3)C15—C16—H22119.1
C1—C2—H8119.7N5—C17—C13122.5 (3)
C3—C2—H8119.7N5—C17—H23118.8
C2—C3—C4118.1 (3)C13—C17—H23118.8
C2—C3—H9120.9N6—C18—H24A109.5
C4—C3—H9120.9N6—C18—H24B109.5
C5—C4—C3118.3 (3)H24A—C18—H24B109.5
C5—C4—N2117.5 (3)N6—C18—H24C109.5
C3—C4—N2124.2 (3)H24A—C18—H24C109.5
N1—C5—C4122.6 (3)H24B—C18—H24C109.5
N1—C5—H11118.7N6—C19—H25A109.5
C4—C5—H11118.7N6—C19—H25B109.5
O1—C6—N2123.9 (4)H25A—C19—H25B109.5
O1—C6—C7120.5 (3)N6—C19—H25C109.5
N2—C6—C7115.5 (3)H25A—C19—H25C109.5
N3—C7—C8123.5 (3)H25B—C19—H25C109.5
N3—C7—C6117.1 (3)O3—C20—N6126.0 (4)
C8—C7—C6119.5 (3)O3—C20—H26117.0
C9—C8—C7118.7 (4)N6—C20—H26117.0
N5i—Hg1—N1—C599.7 (3)C6—C7—C8—C9179.8 (3)
Cl1—Hg1—N1—C5−133.8 (2)C7—C8—C9—C101.4 (6)
Cl2—Hg1—N1—C5−7.2 (3)C8—C9—C10—C11−1.6 (6)
N5i—Hg1—N1—C1−92.7 (3)C7—N3—C11—C100.7 (5)
Cl1—Hg1—N1—C133.8 (3)C7—N3—C11—C12−178.3 (3)
Cl2—Hg1—N1—C1160.5 (3)C9—C10—C11—N30.6 (6)
C5—N1—C1—C20.9 (6)C9—C10—C11—C12179.6 (3)
Hg1—N1—C1—C2−166.7 (3)C13—N4—C12—O22.8 (6)
N1—C1—C2—C3−0.7 (6)C13—N4—C12—C11−177.2 (3)
C1—C2—C3—C4−0.4 (6)N3—C11—C12—O2168.8 (3)
C2—C3—C4—C51.2 (5)C10—C11—C12—O2−10.3 (5)
C2—C3—C4—N2−179.7 (3)N3—C11—C12—N4−11.2 (5)
C6—N2—C4—C5175.5 (4)C10—C11—C12—N4169.7 (3)
C6—N2—C4—C3−3.6 (6)C12—N4—C13—C17129.3 (4)
C1—N1—C5—C40.0 (5)C12—N4—C13—C14−51.0 (5)
Hg1—N1—C5—C4167.8 (3)C17—C13—C14—C151.0 (5)
C3—C4—C5—N1−1.0 (5)N4—C13—C14—C15−178.7 (3)
N2—C4—C5—N1179.8 (3)C13—C14—C15—C16−1.2 (5)
C4—N2—C6—O10.8 (7)C17—N5—C16—C151.1 (5)
C4—N2—C6—C7−179.0 (3)Hg1i—N5—C16—C15−171.3 (3)
C11—N3—C7—C8−0.9 (5)C14—C15—C16—N50.1 (6)
C11—N3—C7—C6179.1 (3)C16—N5—C17—C13−1.2 (5)
O1—C6—C7—N3−179.9 (4)Hg1i—N5—C17—C13171.4 (3)
N2—C6—C7—N30.0 (5)C14—C13—C17—N50.1 (5)
O1—C6—C7—C80.1 (6)N4—C13—C17—N5179.9 (3)
N2—C6—C7—C8−180.0 (3)C19—N6—C20—O32.2 (6)
N3—C7—C8—C9−0.1 (6)C18—N6—C20—O3179.9 (4)
Symmetry codes: (i) −x+1, −y+1, −z+1.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O30.862.323.090 (4)149
N2—H2A···N30.862.272.692 (2)110
N4—H4A···O30.862.062.870 (4)156
N4—H4A···N30.862.332.714 (3)107
Table 1
Selected geometric parameters (Å, °) top
Hg1—N5i2.295 (3)Hg1—Cl12.3994 (12)
Hg1—N12.337 (3)Hg1—Cl22.4249 (14)
N5i—Hg1—N1106.50 (11)N5i—Hg1—Cl2103.20 (9)
N5i—Hg1—Cl1117.02 (8)N1—Hg1—Cl299.40 (8)
N1—Hg1—Cl1108.03 (8)Cl1—Hg1—Cl2120.60 (4)
Symmetry codes: (i) −x+1, −y+1, −z+1.
Table 2
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N2—H2A···O30.862.323.090 (4)149
N2—H2A···N30.862.272.692 (2)110
N4—H4A···O30.862.062.870 (4)156
N4—H4A···N30.862.332.714 (3)107
Acknowledgements top

The authors thank Professor Hou Hong-Wei of Zhengzhou University for his help.

references
References top

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