metal-organic compounds
Dichlorido[N,N-diethyl-N′-(2-pyridylmethylene)ethane-1,2-diamine]mercury(II)
aDepartment of Chemistry Education, Interdisciplinary Program of Advanced Information and Display Materials, and Center for Plastic Information Systems, Pusan National University, Busan 609-735, Republic of Korea, and bDepartment of Chemistry, Chungnam National University, Daejeon 305-764, Republic of Korea
*Correspondence e-mail: skkang@cnu.ac.kr
The Hg atom in the title compound, [HgCl2(C12H19N3)], adopts a distorted trigonal-bipyramidal geometry, being ligated by two Cl atoms and three N atoms of the N,N-diethyl-N′-(2-pyridylmethylene)ethane-1,2-diamine ligand. The dihedral angle between the HgN3 and HgCl2 least-squares planes is 88.6 (1)°. The Hg—N distances including the pyridine N and the ammonium N atom are about 0.20 Å longer than the Hg—N distance including the imino N atom.
Related literature
For general background to luminescent mercury compounds, see: Elena et al. (2006); Durantaye et al. (2006); Fan et al. (2009). For the syntheses and structures of these compounds, see: Kim et al. (2008); Seo et al. (2009).
Experimental
Crystal data
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Refinement
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Data collection: SMART (Bruker, 2002); cell SAINT (Bruker, 2002); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).
Supporting information
https://doi.org/10.1107/S1600536810000103/tk2606sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810000103/tk2606Isup2.hkl
All of the reagents and solvents were purchased from Aldrich and used without further purification. The N,N-diethyl-N'-pyridine-2-ylmethylene-ethene-1,2-diamine (L) was synthesized by reacting N,N-diethyl-ethylenediamine (15 mmol) and 2-pyridinecarboxaldehyde (15 mmol) in methanol (50 ml). The mixture was stirred for 3 h at room temperature and the solution was evaporated to dryness. The residue was extracted with dichloromethane to give depmed as yellow oil. A solution depmed (5 mmol) in methanol (15 ml) was added slowly to a solution of mercuric chloride (5 mmol) in methanol (15 ml). The mixture was stirred for 12 h at room temperature. The resultant precipitate was collected by filtration and washed several times with cool methanol. The precipitate was dried over vacuum in an oven at room temperature. The crystals were obtained by slow evaporation in a methanol solution. Yield: 53%. Anal. Calcd. for C12H19N3Cl2Hg: C, 30.23; H, 4.02; N, 8.81. Found: C, 29.97; H, 4.21; N, 8.76. 1H-NMR (300 MHz, d6-DMSO) δ; 8.95 (1H, d, J=4.2 Hz), 8.57 (1H, s), 7.97 (1H, t, J=7.8 Hz), 7.62–7.68 (2H, m), 3.82 (2H, t, J=6.5 Hz), 2.94–3.08 (6H, m), 1.19 (6H, s).
All H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93 - 0.97 Å, and with Uiso(H) = 1.2Ueq(C) for aromatic- and methylene-H, and 1.5Ueq(C) for methyl-H atoms.
Much attention has been paid to the design and synthesis of luminescent mercury compounds for the detection and extraction of the mercury (Elena et al., 2006; Durantaye et al., 2006), among which, Hg(II) complexes with pyridine-containing ligands are of importance for their high luminescent efficiency (Fan et al., 2009). Recently, we reported Hg(II) compounds with bis(2-pyridylmethyl)amine (Kim et al., 2008) and with benzyl(2-pyridylmethyl)amine (Seo et al., 2009) as a development of blue fluorescent materials. In this work, we prepared a Hg(II) complex with N,N-diethyl-N'-pyridine-2-ylmethylene-ethene-1,2-diamine (depmed), and its structure and luminescent properties were investigated.
In the title compound, (I), the Hg atom is 5-coordinated by two Cl atoms and three N atoms of the tridentate depmed ligand. The coordination geometry around Hg atom is based on a distorted trigonal bipyramid with the equatorial plane defined by N8, Cl1, and Cl2 atoms, with the other N atoms occupying axial positions. The dihedral angle between the least-squares planes through the N1/N8/N11/Hg atoms and that through the HgCl2 atoms is 88.6 (1)°; the bond angle of N1—Hg—N11 is 139.2 (1)°. The Hg–N1 and Hg–N11 bond distances are each about 0.20Å longer than the Hg–N8 bond distance, Table 1.
The free ligand (depmed) showed strong blue (λmax,PL = 491 nm in DMF) fluorescent emissions upon 280 nm excitation, while Hg(depmed)Cl2 displayed two blue emission (λmax,PL = 309 and 389 nm in DMF) which was tentatively assigned to be an intraligand (IL) 1π-π* transition. The PL (f) versus 9,10-diphenylanthracene was measured to be 0.29% and 0.04% for free ligand (depmed) and Hg(depmed)Cl2, respectively.
For general background to luminescent mercury compounds, see: Elena et al. (2006); Durantaye et al. (2006); Fan et al. (2009). For the syntheses and structures of these compounds, see: Kim et al. (2008); Seo et al. (2009).
Data collection: SMART (Bruker, 2002); cell
SAINT (Bruker, 2002); data reduction: SAINT (Bruker, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).Fig. 1. Molecular structure of (I), showing the atom-numbering scheme and 30% probability ellipsoids. |
[HgCl2(C12H19N3)] | F(000) = 904 |
Mr = 476.79 | Dx = 1.948 Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 5949 reflections |
a = 8.0028 (5) Å | θ = 2.5–26.4° |
b = 16.6507 (9) Å | µ = 9.79 mm−1 |
c = 12.4541 (8) Å | T = 295 K |
β = 101.630 (5)° | Block, colourless |
V = 1625.47 (17) Å3 | 0.27 × 0.24 × 0.23 mm |
Z = 4 |
Bruker SMART CCD area-detector diffractometer | 3124 reflections with I > 2σ(I) |
φ and ω scans | Rint = 0.029 |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | θmax = 28.3°, θmin = 2.1° |
Tmin = 0.085, Tmax = 0.102 | h = −10→10 |
17026 measured reflections | k = −22→22 |
4039 independent reflections | l = −14→16 |
Refinement on F2 | 0 restraints |
Least-squares matrix: full | H-atom parameters constrained |
R[F2 > 2σ(F2)] = 0.026 | w = 1/[σ2(Fo2) + (0.026P)2 + 0.5659P] where P = (Fo2 + 2Fc2)/3 |
wR(F2) = 0.059 | (Δ/σ)max = 0.001 |
S = 1.04 | Δρmax = 0.71 e Å−3 |
4039 reflections | Δρmin = −0.92 e Å−3 |
163 parameters |
[HgCl2(C12H19N3)] | V = 1625.47 (17) Å3 |
Mr = 476.79 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 8.0028 (5) Å | µ = 9.79 mm−1 |
b = 16.6507 (9) Å | T = 295 K |
c = 12.4541 (8) Å | 0.27 × 0.24 × 0.23 mm |
β = 101.630 (5)° |
Bruker SMART CCD area-detector diffractometer | 4039 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2002) | 3124 reflections with I > 2σ(I) |
Tmin = 0.085, Tmax = 0.102 | Rint = 0.029 |
17026 measured reflections |
R[F2 > 2σ(F2)] = 0.026 | 0 restraints |
wR(F2) = 0.059 | H-atom parameters constrained |
S = 1.04 | Δρmax = 0.71 e Å−3 |
4039 reflections | Δρmin = −0.92 e Å−3 |
163 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Hg1 | 0.208069 (19) | 0.190628 (9) | 0.561325 (12) | 0.05266 (7) | |
Cl1 | 0.04834 (16) | 0.20511 (8) | 0.70474 (10) | 0.0766 (3) | |
Cl2 | 0.06896 (15) | 0.15227 (8) | 0.37542 (9) | 0.0756 (3) | |
N1 | 0.3474 (4) | 0.0549 (2) | 0.6108 (3) | 0.0533 (8) | |
C2 | 0.2740 (6) | −0.0156 (3) | 0.6201 (4) | 0.0654 (11) | |
H2 | 0.1555 | −0.0177 | 0.6057 | 0.078* | |
C3 | 0.3629 (7) | −0.0862 (3) | 0.6499 (4) | 0.0697 (12) | |
H3 | 0.3058 | −0.1342 | 0.6553 | 0.084* | |
C4 | 0.5359 (7) | −0.0830 (3) | 0.6708 (4) | 0.0731 (13) | |
H4 | 0.5996 | −0.1292 | 0.6915 | 0.088* | |
C5 | 0.6169 (6) | −0.0108 (3) | 0.6612 (3) | 0.0659 (11) | |
H5 | 0.7353 | −0.0078 | 0.6745 | 0.079* | |
C6 | 0.5184 (5) | 0.0570 (2) | 0.6313 (3) | 0.0527 (9) | |
C7 | 0.5949 (5) | 0.1352 (3) | 0.6185 (3) | 0.0584 (10) | |
H7 | 0.713 | 0.1391 | 0.6283 | 0.07* | |
N8 | 0.5056 (4) | 0.19763 (19) | 0.5946 (3) | 0.0554 (8) | |
C9 | 0.5810 (6) | 0.2749 (3) | 0.5783 (4) | 0.0706 (12) | |
H9A | 0.6906 | 0.2671 | 0.5578 | 0.085* | |
H9B | 0.599 | 0.3057 | 0.6458 | 0.085* | |
C10 | 0.4618 (7) | 0.3196 (2) | 0.4886 (4) | 0.0721 (14) | |
H10A | 0.5111 | 0.3715 | 0.4782 | 0.087* | |
H10B | 0.451 | 0.2899 | 0.4206 | 0.087* | |
N11 | 0.2900 (5) | 0.33175 (19) | 0.5129 (3) | 0.0545 (8) | |
C12 | 0.2909 (6) | 0.3827 (2) | 0.6098 (3) | 0.0597 (10) | |
H12A | 0.3544 | 0.3549 | 0.6736 | 0.072* | |
H12B | 0.1743 | 0.388 | 0.6197 | 0.072* | |
C13 | 0.3658 (7) | 0.4666 (3) | 0.6073 (4) | 0.0860 (15) | |
H13A | 0.3604 | 0.4942 | 0.6742 | 0.129* | |
H13B | 0.3016 | 0.496 | 0.5463 | 0.129* | |
H13C | 0.4825 | 0.4627 | 0.5996 | 0.129* | |
C14 | 0.1738 (7) | 0.3608 (3) | 0.4138 (4) | 0.0836 (15) | |
H14A | 0.1783 | 0.3241 | 0.354 | 0.1* | |
H14B | 0.2134 | 0.4128 | 0.3942 | 0.1* | |
C15 | −0.0096 (8) | 0.3686 (4) | 0.4267 (5) | 0.112 (2) | |
H15A | −0.0782 | 0.3881 | 0.3595 | 0.168* | |
H15B | −0.0157 | 0.4057 | 0.4849 | 0.168* | |
H15C | −0.051 | 0.3171 | 0.444 | 0.168* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Hg1 | 0.04281 (9) | 0.06545 (11) | 0.05013 (10) | −0.00279 (7) | 0.01033 (7) | 0.00321 (7) |
Cl1 | 0.0616 (7) | 0.1078 (9) | 0.0680 (7) | −0.0054 (6) | 0.0312 (6) | −0.0045 (6) |
Cl2 | 0.0637 (7) | 0.0923 (8) | 0.0615 (7) | −0.0041 (6) | −0.0097 (6) | −0.0122 (6) |
N1 | 0.0474 (18) | 0.065 (2) | 0.0478 (18) | 0.0010 (15) | 0.0114 (15) | 0.0030 (15) |
C2 | 0.060 (3) | 0.076 (3) | 0.066 (3) | −0.002 (2) | 0.025 (2) | 0.011 (2) |
C3 | 0.082 (3) | 0.070 (3) | 0.065 (3) | −0.001 (2) | 0.033 (3) | 0.011 (2) |
C4 | 0.092 (4) | 0.068 (3) | 0.062 (3) | 0.023 (3) | 0.024 (3) | 0.014 (2) |
C5 | 0.057 (3) | 0.080 (3) | 0.059 (3) | 0.020 (2) | 0.009 (2) | 0.000 (2) |
C6 | 0.051 (2) | 0.067 (2) | 0.040 (2) | 0.0014 (19) | 0.0081 (17) | −0.0043 (17) |
C7 | 0.037 (2) | 0.080 (3) | 0.058 (2) | 0.003 (2) | 0.0084 (18) | −0.014 (2) |
N8 | 0.0451 (18) | 0.066 (2) | 0.057 (2) | −0.0078 (15) | 0.0133 (16) | −0.0080 (16) |
C9 | 0.052 (3) | 0.069 (3) | 0.095 (4) | −0.008 (2) | 0.025 (3) | −0.004 (3) |
C10 | 0.089 (4) | 0.063 (3) | 0.078 (3) | −0.019 (2) | 0.050 (3) | −0.005 (2) |
N11 | 0.065 (2) | 0.0620 (19) | 0.0372 (17) | −0.0039 (16) | 0.0116 (16) | 0.0066 (14) |
C12 | 0.068 (3) | 0.066 (3) | 0.047 (2) | 0.003 (2) | 0.016 (2) | 0.0030 (19) |
C13 | 0.115 (4) | 0.070 (3) | 0.078 (3) | −0.006 (3) | 0.031 (3) | −0.012 (3) |
C14 | 0.115 (5) | 0.080 (3) | 0.048 (3) | −0.004 (3) | −0.003 (3) | 0.019 (2) |
C15 | 0.099 (5) | 0.117 (5) | 0.102 (4) | 0.024 (4) | −0.024 (4) | 0.018 (4) |
Hg1—Cl1 | 2.4088 (11) | C9—H9A | 0.97 |
Hg1—Cl2 | 2.4431 (11) | C9—H9B | 0.97 |
Hg1—N1 | 2.540 (3) | C10—N11 | 1.480 (6) |
Hg1—N8 | 2.336 (3) | C10—H10A | 0.97 |
Hg1—N11 | 2.544 (3) | C10—H10B | 0.97 |
N1—C2 | 1.328 (5) | N11—C14 | 1.470 (5) |
N1—C6 | 1.341 (5) | N11—C12 | 1.473 (5) |
C2—C3 | 1.385 (6) | C12—C13 | 1.524 (6) |
C2—H2 | 0.93 | C12—H12A | 0.97 |
C3—C4 | 1.357 (6) | C12—H12B | 0.97 |
C3—H3 | 0.93 | C13—H13A | 0.96 |
C4—C5 | 1.384 (6) | C13—H13B | 0.96 |
C4—H4 | 0.93 | C13—H13C | 0.96 |
C5—C6 | 1.383 (6) | C14—C15 | 1.514 (8) |
C5—H5 | 0.93 | C14—H14A | 0.97 |
C6—C7 | 1.462 (6) | C14—H14B | 0.97 |
C7—N8 | 1.262 (5) | C15—H15A | 0.96 |
C7—H7 | 0.93 | C15—H15B | 0.96 |
N8—C9 | 1.452 (5) | C15—H15C | 0.96 |
C9—C10 | 1.511 (7) | ||
N8—Hg1—Cl1 | 122.54 (9) | C10—C9—H9B | 109.9 |
N8—Hg1—Cl2 | 115.75 (9) | H9A—C9—H9B | 108.3 |
Cl1—Hg1—Cl2 | 121.35 (4) | N11—C10—C9 | 113.0 (3) |
N8—Hg1—N1 | 67.63 (11) | N11—C10—H10A | 109 |
Cl1—Hg1—N1 | 100.47 (8) | C9—C10—H10A | 109 |
Cl2—Hg1—N1 | 95.24 (8) | N11—C10—H10B | 109 |
N8—Hg1—N11 | 72.16 (12) | C9—C10—H10B | 109 |
Cl1—Hg1—N11 | 106.49 (8) | H10A—C10—H10B | 107.8 |
Cl2—Hg1—N11 | 96.14 (8) | C14—N11—C12 | 113.3 (4) |
N1—Hg1—N11 | 139.24 (11) | C14—N11—C10 | 109.3 (4) |
C2—N1—C6 | 117.3 (4) | C12—N11—C10 | 113.2 (4) |
C2—N1—Hg1 | 128.9 (3) | C14—N11—Hg1 | 110.7 (3) |
C6—N1—Hg1 | 113.9 (3) | C12—N11—Hg1 | 107.2 (2) |
N1—C2—C3 | 124.1 (4) | C10—N11—Hg1 | 102.5 (2) |
N1—C2—H2 | 117.9 | N11—C12—C13 | 116.6 (3) |
C3—C2—H2 | 117.9 | N11—C12—H12A | 108.1 |
C4—C3—C2 | 117.9 (4) | C13—C12—H12A | 108.1 |
C4—C3—H3 | 121.1 | N11—C12—H12B | 108.1 |
C2—C3—H3 | 121.1 | C13—C12—H12B | 108.1 |
C3—C4—C5 | 119.6 (4) | H12A—C12—H12B | 107.3 |
C3—C4—H4 | 120.2 | C12—C13—H13A | 109.5 |
C5—C4—H4 | 120.2 | C12—C13—H13B | 109.5 |
C6—C5—C4 | 118.7 (4) | H13A—C13—H13B | 109.5 |
C6—C5—H5 | 120.6 | C12—C13—H13C | 109.5 |
C4—C5—H5 | 120.6 | H13A—C13—H13C | 109.5 |
N1—C6—C5 | 122.4 (4) | H13B—C13—H13C | 109.5 |
N1—C6—C7 | 115.8 (3) | N11—C14—C15 | 113.7 (4) |
C5—C6—C7 | 121.8 (4) | N11—C14—H14A | 108.8 |
N8—C7—C6 | 122.0 (4) | C15—C14—H14A | 108.8 |
N8—C7—H7 | 119 | N11—C14—H14B | 108.8 |
C6—C7—H7 | 119 | C15—C14—H14B | 108.8 |
C7—N8—C9 | 122.0 (4) | H14A—C14—H14B | 107.7 |
C7—N8—Hg1 | 120.6 (3) | C14—C15—H15A | 109.5 |
C9—N8—Hg1 | 117.2 (3) | C14—C15—H15B | 109.5 |
N8—C9—C10 | 108.7 (4) | H15A—C15—H15B | 109.5 |
N8—C9—H9A | 109.9 | C14—C15—H15C | 109.5 |
C10—C9—H9A | 109.9 | H15A—C15—H15C | 109.5 |
N8—C9—H9B | 109.9 | H15B—C15—H15C | 109.5 |
Experimental details
Crystal data | |
Chemical formula | [HgCl2(C12H19N3)] |
Mr | 476.79 |
Crystal system, space group | Monoclinic, P21/n |
Temperature (K) | 295 |
a, b, c (Å) | 8.0028 (5), 16.6507 (9), 12.4541 (8) |
β (°) | 101.630 (5) |
V (Å3) | 1625.47 (17) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 9.79 |
Crystal size (mm) | 0.27 × 0.24 × 0.23 |
Data collection | |
Diffractometer | Bruker SMART CCD area-detector |
Absorption correction | Multi-scan (SADABS; Bruker, 2002) |
Tmin, Tmax | 0.085, 0.102 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 17026, 4039, 3124 |
Rint | 0.029 |
(sin θ/λ)max (Å−1) | 0.667 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.026, 0.059, 1.04 |
No. of reflections | 4039 |
No. of parameters | 163 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.71, −0.92 |
Computer programs: SMART (Bruker, 2002), SAINT (Bruker, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).
Hg1—Cl1 | 2.4088 (11) | Hg1—N8 | 2.336 (3) |
Hg1—Cl2 | 2.4431 (11) | Hg1—N11 | 2.544 (3) |
Hg1—N1 | 2.540 (3) |
Acknowledgements
This work was supported by the National Research Foundation of Korea Grant funded by the Korean Government (NO. 2009–0066594).
References
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Much attention has been paid to the design and synthesis of luminescent mercury compounds for the detection and extraction of the mercury (Elena et al., 2006; Durantaye et al., 2006), among which, Hg(II) complexes with pyridine-containing ligands are of importance for their high luminescent efficiency (Fan et al., 2009). Recently, we reported Hg(II) compounds with bis(2-pyridylmethyl)amine (Kim et al., 2008) and with benzyl(2-pyridylmethyl)amine (Seo et al., 2009) as a development of blue fluorescent materials. In this work, we prepared a Hg(II) complex with N,N-diethyl-N'-pyridine-2-ylmethylene-ethene-1,2-diamine (depmed), and its structure and luminescent properties were investigated.
In the title compound, (I), the Hg atom is 5-coordinated by two Cl atoms and three N atoms of the tridentate depmed ligand. The coordination geometry around Hg atom is based on a distorted trigonal bipyramid with the equatorial plane defined by N8, Cl1, and Cl2 atoms, with the other N atoms occupying axial positions. The dihedral angle between the least-squares planes through the N1/N8/N11/Hg atoms and that through the HgCl2 atoms is 88.6 (1)°; the bond angle of N1—Hg—N11 is 139.2 (1)°. The Hg–N1 and Hg–N11 bond distances are each about 0.20Å longer than the Hg–N8 bond distance, Table 1.
The free ligand (depmed) showed strong blue (λmax,PL = 491 nm in DMF) fluorescent emissions upon 280 nm excitation, while Hg(depmed)Cl2 displayed two blue emission (λmax,PL = 309 and 389 nm in DMF) which was tentatively assigned to be an intraligand (IL) 1π-π* transition. The PL quantum yield (f) versus 9,10-diphenylanthracene was measured to be 0.29% and 0.04% for free ligand (depmed) and Hg(depmed)Cl2, respectively.