Di-μ-chlorido-bis­{[2-(benzyl­imino­meth­yl)pyridine-κ² N,N′]chloridomercury(II)} dichloridomercury(II)

Abstract

The Hg^II ion in the title centrosymmetric dinuclear complex, [Hg₂Cl₄(C₁₃H₁₂N₂)₂]·[HgCl₂], adopts a distorted square-pyramidal geometry, being coordinated by the bis-chelating N-heterocyclic ligand, two bridging Cl atoms and one terminal Cl atom. One of the bridging Hg—Cl bonds [2.8428 (11) Å] is significantly longer than the other [2.5327 (10) Å]. In the crystal, there are weak π–π inter­actions [centroid–centroid distance = 3.630 (3) Å] between the aromatic rings of the discrete units. The HgCl₂ adduct molecule is located on an inversion centre and has an Hg—Cl bond length of 2.2875 (11) Å.

Related literature

For general background to luminescent mercury compounds, see: Elena et al. (2006 ▶); Durantaye et al. (2006 ▶); Fan et al. (2009 ▶); He et al. (2008 ▶). For syntheses and structures of Hg(II) complexes, see: Kim & Kang (2010 ▶); Kim et al. (2010 ▶).

Experimental

Crystal data

• [Hg₂Cl₄(C₁₃H₁₂N₂)₂]·[HgCl₂]

• M _r = 1206.96

• Monoclinic,

• a = 10.1329 (2) Å

• b = 8.1141 (1) Å

• c = 19.0591 (2) Å

• β = 92.939 (1)°

• V = 1564.97 (4) ų

• Z = 2

• Mo Kα radiation

• μ = 15.22 mm⁻¹

• T = 295 K

• 0.17 × 0.13 × 0.12 mm

Data collection

• Bruker SMART CCD area-detector diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2002 ▶) T _min = 0.104, T _max = 0.158

• 16269 measured reflections

• 3892 independent reflections

• 3279 reflections with I > 2σ(I)

• R _int = 0.027

Refinement

• R[F ² > 2σ(F ²)] = 0.025

• wR(F ²) = 0.055

• S = 1.04

• 3892 reflections

• 178 parameters

• H-atom parameters constrained

• Δρ_max = 1.21 e Å⁻³

• Δρ_min = −1.18 e Å⁻³

Data collection: SMART (Bruker, 2002 ▶); cell refinement: 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 ▶).

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Selected geometric parameters (Å, °).

Hg1—N8	2.347 (4)
Hg1—N1	2.373 (3)
Hg1—Cl1	2.4338 (12)

N8—Hg1—N1	70.74 (12)
N8—Hg1—Cl1	113.97 (9)
N1—Hg1—Cl1	106.32 (9)
N8—Hg1—Cl2	95.92 (9)
N1—Hg1—Cl2	138.01 (8)
Cl1—Hg1—Cl2	115.34 (4)
N8—Hg1—Cl2i	142.19 (9)
N1—Hg1—Cl2i	83.87 (8)
Cl1—Hg1—Cl2i	99.58 (4)
Cl2—Hg1—Cl2i	84.37 (3)

Symmetry code: (i) .

supplementary crystallographic information

Comment

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). In a previous report (Kim & Kang, 2010), we presented a structure of white Hg(II) complex with benzyl(2-pyridylmethylene)amine(bpma), (bpma)HgCl₂, concerning its luminescence behavior (Kim et al., 2010; He et al., 2008). The reported white crystals were obtained after recrystallization from methanol solution in a day. However, we could find another yellow crystals in 3–4 days in the same solution. Herein, we report the structure of separated yellow crystals, [(bpma)HgCl₂]₂ HgCl₂.

In (I), Fig. 1, the Hg1^II ion is coordinated by two N atoms of heterocyclic ligand, two bridging Cl atoms and one terminal Cl atom. The angles around Hg1 atoms are in the range of 70.74 (12) – 142.19 (9)°, suggesting the coordination geometry around the Hg1 atom is described as a distorted square pyrdmid with an apical position of Cl1 atom. One of the bridging Hg1—Cl bonds (2.843 (1) Å) is significantly longer than the other (2.533 (1) Å). The phenyl ring on the bpma ligand is twisted out of the pyridine plane, and form a dihedral angel of 81.21 (11)°. In the crystal structure, there are weak π-π interactions [centroid-centroid distance = 3.630 (3) Å] between the aromatic rings of the discrete units.

Experimental

Benzyl(2-pyridylmethylene)amine (bpma) was synthesized from the reaction of 2-pyridinecarboxylaldehyde and benzylamine. And bpma reacted with mercury dichloride in methanol to yield the titled complex. The yellow crystals were separated from white crystals in 3–4 days from methanol solution. The detailed synthetic method was previously reported (Kim & Kang, 2010).

Refinement

All H atoms were positioned geometrically and refined using a riding model, with C—H = 0.93 - 0.97 Å, and with U_iso(H) = 1.2U_eq(C). The maximum and minimum residual electron density peaks were located at 0.79 and 0.63 Å, respectively, from the Hg1 atom.

Figures

Fig. 1.

Molecular structure of (I), showing the atom-numbering scheme and 30% probability ellipsoids [symmetry code: (i) -x, -y + 1, -z; (ii) -x, -y + 2, -z].

Crystal data

[Hg2Cl4(C13H12N2)2]·[HgCl2]	F(000) = 1100
Mr = 1206.96	Dx = 2.561 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 5840 reflections
a = 10.1329 (2) Å	θ = 2.2–28.0°
b = 8.1141 (1) Å	µ = 15.22 mm−1
c = 19.0591 (2) Å	T = 295 K
β = 92.939 (1)°	Block, yellow
V = 1564.97 (4) Å3	0.17 × 0.13 × 0.12 mm
Z = 2

Data collection

Bruker SMART CCD area-detector diffractometer	3279 reflections with I > 2σ(I)
φ and ω scans	Rint = 0.027
Absorption correction: multi-scan (SADABS; Bruker, 2002)	θmax = 28.3°, θmin = 2.1°
Tmin = 0.104, Tmax = 0.158	h = −13→10
16269 measured reflections	k = −10→10
3892 independent reflections	l = −25→25

Refinement

Refinement on F2	0 restraints
Least-squares matrix: full	H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.025	w = 1/[σ2(Fo2) + (0.025P)2 + 1.1429P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.055	(Δ/σ)max < 0.001
S = 1.04	Δρmax = 1.21 e Å−3
3892 reflections	Δρmin = −1.18 e Å−3
178 parameters

Special details

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
Hg1	0.092853 (16)	0.45122 (2)	0.092463 (9)	0.04770 (6)
Cl1	0.02059 (13)	0.19456 (15)	0.14429 (6)	0.0625 (3)
Cl2	−0.09059 (10)	0.64548 (14)	0.05096 (6)	0.0503 (3)
N1	0.3257 (3)	0.4310 (4)	0.08642 (17)	0.0395 (7)
C2	0.3903 (5)	0.3289 (6)	0.0459 (2)	0.0515 (11)
H2	0.3421	0.2636	0.0137	0.062*
C3	0.5252 (5)	0.3161 (7)	0.0498 (3)	0.0637 (14)
H3	0.5671	0.2431	0.0206	0.076*
C4	0.5977 (5)	0.4107 (8)	0.0965 (3)	0.0700 (17)
H4	0.6895	0.4035	0.0997	0.084*
C5	0.5319 (5)	0.5178 (7)	0.1392 (3)	0.0623 (14)
H5	0.5789	0.5839	0.1716	0.075*
C6	0.3952 (4)	0.5253 (5)	0.1331 (2)	0.0422 (9)
C7	0.3196 (4)	0.6329 (5)	0.1779 (2)	0.0457 (10)
H7	0.3644	0.7015	0.2101	0.055*
N8	0.1950 (4)	0.6345 (4)	0.17363 (18)	0.0451 (8)
C9	0.1223 (6)	0.7461 (6)	0.2188 (3)	0.0658 (14)
H9A	0.0734	0.8259	0.1899	0.079*
H9B	0.1844	0.8057	0.2498	0.079*
C10	0.0277 (4)	0.6506 (6)	0.2621 (2)	0.0495 (10)
C11	−0.1060 (5)	0.6560 (8)	0.2474 (3)	0.0740 (16)
H11	−0.1404	0.7177	0.2096	0.089*
C12	−0.1907 (5)	0.5681 (11)	0.2896 (3)	0.090 (2)
H12	−0.2816	0.5723	0.28	0.108*
C13	−0.1409 (6)	0.4767 (8)	0.3446 (3)	0.0747 (17)
H13	−0.1975	0.4182	0.3724	0.09*
C14	−0.0083 (6)	0.4711 (6)	0.3589 (3)	0.0625 (13)
H14	0.0259	0.4081	0.3963	0.075*
C15	0.0756 (5)	0.5576 (5)	0.3184 (3)	0.0531 (11)
H15	0.1662	0.5537	0.329	0.064*
Hg2	0	1	0	0.04776 (7)
Cl3	0.21296 (11)	0.91503 (18)	0.02343 (7)	0.0664 (3)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Hg1	0.03772 (9)	0.05296 (12)	0.05168 (11)	−0.00140 (7)	−0.00498 (7)	0.00188 (7)
Cl1	0.0824 (8)	0.0537 (7)	0.0518 (6)	−0.0145 (6)	0.0082 (6)	0.0031 (5)
Cl2	0.0455 (6)	0.0592 (7)	0.0456 (6)	0.0081 (5)	−0.0034 (4)	0.0008 (5)
N1	0.0362 (17)	0.0416 (19)	0.0408 (18)	−0.0014 (14)	0.0015 (14)	0.0033 (15)
C2	0.058 (3)	0.047 (3)	0.050 (3)	0.005 (2)	0.009 (2)	0.001 (2)
C3	0.063 (3)	0.062 (3)	0.068 (3)	0.018 (3)	0.024 (3)	0.020 (3)
C4	0.037 (2)	0.083 (4)	0.091 (4)	0.011 (3)	0.014 (3)	0.040 (3)
C5	0.046 (3)	0.069 (3)	0.071 (3)	−0.014 (2)	−0.012 (2)	0.021 (3)
C6	0.037 (2)	0.044 (2)	0.045 (2)	−0.0056 (16)	−0.0036 (17)	0.0101 (18)
C7	0.057 (3)	0.041 (2)	0.039 (2)	−0.0116 (19)	−0.0028 (18)	0.0030 (17)
N8	0.058 (2)	0.0355 (19)	0.0425 (19)	0.0052 (15)	0.0057 (16)	−0.0015 (14)
C9	0.094 (4)	0.043 (3)	0.063 (3)	0.011 (3)	0.020 (3)	−0.008 (2)
C10	0.056 (3)	0.045 (2)	0.048 (2)	0.010 (2)	0.007 (2)	−0.0124 (19)
C11	0.065 (3)	0.101 (4)	0.054 (3)	0.025 (3)	−0.008 (3)	−0.008 (3)
C12	0.043 (3)	0.154 (7)	0.071 (4)	−0.004 (3)	0.000 (3)	−0.034 (4)
C13	0.073 (4)	0.096 (5)	0.056 (3)	−0.025 (3)	0.013 (3)	−0.019 (3)
C14	0.073 (4)	0.055 (3)	0.060 (3)	−0.001 (2)	0.006 (3)	−0.006 (2)
C15	0.049 (3)	0.048 (3)	0.063 (3)	0.005 (2)	0.002 (2)	−0.009 (2)
Hg2	0.03219 (11)	0.05415 (15)	0.05669 (15)	0.00592 (9)	−0.00021 (10)	0.00053 (11)
Cl3	0.0374 (6)	0.0813 (9)	0.0799 (9)	0.0158 (6)	−0.0035 (5)	0.0004 (7)

Geometric parameters (Å, °)

Hg1—N8	2.347 (4)	C7—H7	0.93
Hg1—N1	2.373 (3)	N8—C9	1.473 (5)
Hg1—Cl1	2.4338 (12)	C9—C10	1.510 (7)
Hg1—Cl2	2.5327 (10)	C9—H9A	0.97
Hg1—Cl2i	2.8428 (11)	C9—H9B	0.97
Cl2—Hg1i	2.8428 (11)	C10—C11	1.370 (7)
N1—C2	1.328 (5)	C10—C15	1.379 (6)
N1—C6	1.345 (5)	C11—C12	1.402 (9)
C2—C3	1.369 (6)	C11—H11	0.93
C2—H2	0.93	C12—C13	1.360 (10)
C3—C4	1.363 (8)	C12—H12	0.93
C3—H3	0.93	C13—C14	1.359 (8)
C4—C5	1.385 (8)	C13—H13	0.93
C4—H4	0.93	C14—C15	1.371 (7)
C5—C6	1.385 (6)	C14—H14	0.93
C5—H5	0.93	C15—H15	0.93
C6—C7	1.465 (6)	Hg2—Cl3ii	2.2875 (11)
C7—N8	1.262 (5)	Hg2—Cl3	2.2875 (11)
N8—Hg1—N1	70.74 (12)	N8—C7—H7	119.3
N8—Hg1—Cl1	113.97 (9)	C6—C7—H7	119.3
N1—Hg1—Cl1	106.32 (9)	C7—N8—C9	119.8 (4)
N8—Hg1—Cl2	95.92 (9)	C7—N8—Hg1	116.2 (3)
N1—Hg1—Cl2	138.01 (8)	C9—N8—Hg1	123.9 (3)
Cl1—Hg1—Cl2	115.34 (4)	N8—C9—C10	110.8 (4)
N8—Hg1—Cl2i	142.19 (9)	N8—C9—H9A	109.5
N1—Hg1—Cl2i	83.87 (8)	C10—C9—H9A	109.5
Cl1—Hg1—Cl2i	99.58 (4)	N8—C9—H9B	109.5
Cl2—Hg1—Cl2i	84.37 (3)	C10—C9—H9B	109.5
Hg1—Cl2—Hg1i	95.63 (3)	H9A—C9—H9B	108.1
C2—N1—C6	118.8 (4)	C11—C10—C15	118.8 (5)
C2—N1—Hg1	126.3 (3)	C11—C10—C9	121.4 (5)
C6—N1—Hg1	114.7 (3)	C15—C10—C9	119.8 (4)
N1—C2—C3	122.5 (5)	C10—C11—C12	119.6 (5)
N1—C2—H2	118.8	C10—C11—H11	120.2
C3—C2—H2	118.8	C12—C11—H11	120.2
C4—C3—C2	119.8 (5)	C13—C12—C11	120.4 (5)
C4—C3—H3	120.1	C13—C12—H12	119.8
C2—C3—H3	120.1	C11—C12—H12	119.8
C3—C4—C5	118.5 (5)	C14—C13—C12	119.8 (6)
C3—C4—H4	120.7	C14—C13—H13	120.1
C5—C4—H4	120.7	C12—C13—H13	120.1
C4—C5—C6	119.2 (5)	C13—C14—C15	120.4 (5)
C4—C5—H5	120.4	C13—C14—H14	119.8
C6—C5—H5	120.4	C15—C14—H14	119.8
N1—C6—C5	121.2 (4)	C14—C15—C10	120.9 (5)
N1—C6—C7	116.9 (4)	C14—C15—H15	119.5
C5—C6—C7	121.8 (4)	C10—C15—H15	119.5
N8—C7—C6	121.4 (4)	Cl3ii—Hg2—Cl3	180

Symmetry codes: (i) −x, −y+1, −z; (ii) −x, −y+2, −z.