(4,4′-Dimethyl-2,2′-bipyridine-κ2N,N′)diiodidomercury(II)

Yousefi, M.; Tadayon Pour, N.; Amani, V.; Khavasi, H.R.

doi:10.1107/S1600536808028791

metal-organic compounds

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ISSN: 2056-9890

Volume 64| Part 10| October 2008| Page m1259

doi:10.1107/S1600536808028791

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(4,4′-Dimethyl-2,2′-bipyridine-κ²N,N′)diiodidomercury(II)

Mohammad Yousefi,^a Nasim Tadayon Pour,^a Vahid Amani ^a ^* and Hamid Reza Khavasi ^b

^aIslamic Azad University, Shahr-e-Rey Branch, Tehran, Iran, and ^bDepartment of Chemistry, Shahid Beheshti University, Tehran 1983963113, Iran
^*Correspondence e-mail: v_amani2002@yahoo.com

(Received 5 September 2008; accepted 8 September 2008; online 13 September 2008)

In the molecule of the title compound, [HgI₂(C₁₂H₁₂N₂)], the Hg^II atom is four-coordinated in a distorted tetrahedral configuration by two N atoms from the 4,4′-dimethyl-2,2′-bipyridine ligand and by two I atoms. There is a π–π contact between the pyridine rings [centroid–centroid distance = 3.775 (6) Å].

Related literature

For related literature, see: Khalighi et al. (2008 ); Ahmadi et al. (2008 ); Khavasi et al. (2008 ); Freire et al. (1999 ); Chen et al. (2006 ); Htoon & Ladd (1976 ).

Experimental

Crystal data

[HgI₂(C₁₂H₁₂N₂)]
M_r = 638.63
Triclinic, $[P \overline 1]$
a = 8.4214 (9) Å
b = 9.8391 (10) Å
c = 10.2983 (10) Å
α = 69.383 (8)°
β = 88.448 (8)°
γ = 74.670 (8)°
V = 768.18 (14) Å³
Z = 2
Mo Kα radiation
μ = 14.02 mm⁻¹
T = 298 (2) K
0.38 × 0.25 × 0.12 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1998 ) T_min = 0.022, T_max = 0.183
8874 measured reflections
4123 independent reflections
3467 reflections with I > 2σ(I)
R_int = 0.091

Refinement

R[F² > 2σ(F²)] = 0.048
wR(F²) = 0.159
S = 0.95
4123 reflections
155 parameters
H-atom parameters constrained
Δρ_max = 1.95 e Å⁻³
Δρ_min = −1.38 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Hg1—I1	2.6671 (9)
Hg1—I2	2.6885 (8)
N1—Hg1	2.442 (8)
N2—Hg1	2.402 (10)

I1—Hg1—I2	132.56 (3)
N1—Hg1—I1	111.9 (2)
N1—Hg1—I2	92.87 (19)
N2—Hg1—N1	67.3 (3)
N2—Hg1—I1	104.9 (2)
N2—Hg1—I2	122.2 (2)

Data collection: SMART (Bruker, 1998 ); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808028791/hk2525sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808028791/hk2525Isup2.hkl

checkCIF report

Comment top

Recently, we reported the syntheses and crystal structures of [Zn(5,5'-dmbpy)Cl₂], (II), (Khalighi et al., 2008), [Cd(5,5'-dmbpy)(µ-Cl)₂]_n, (III), (Ahmadi et al., 2008) and {[HgCl(dm4bt)]₂(µ-Cl)₂}, (IV), (Khavasi et al., 2008) [where 5,5'-dmbpy is 5,5'-dimethyl-2,2'-bipyridine and dm4bt is 2,2'-dimethyl-4,4' -bithiazole]. There are several Hg^II complexes, with formula, [HgI₂(N-N)], such as [HgI₂(bipy)], (V), [HgI₂(phen)], (VI), [HgI₂(2,9-dmphen)], (VII), (Freire et al., 1999), [HgI₂(bipy)][HgI₂], (VIII), (Chen et al., 2006) and [HgI₂(TMDA)], (IX), (Htoon & Ladd, 1976) [where bipy is 2,2'-bipyridine, phen is 1,10-phenanthroline, dmphen is 2,9-dimethyl-1,10-phenanthroline and TMDA is tetramethylethylenediamine] have been synthesized and characterized by single-crystal X-ray diffraction methods. We report herein the synthesis and crystal structure of the title compound, (I).

In the title compound, (I), (Fig. 1), the Hg^II atom is four-coordinated in a distorted tetrahedral configuration by two N atoms from 4,4'-dimethyl-2,2'-bipyridine and two I atoms. The Hg—I and Hg—N bond lengths and angles (Table 1) are within normal ranges, as in (V) and (VI).

In the crystal structure, the π–π contact (Fig. 2) between the pyridine rings, Cg2···Cg3ⁱ [symmetry code: (i) 1 - x, -y, -z, where Cg2 and Cg3 are the centroids of the rings (N1/C1–C3/C5/C6) and (N2/C7–C9/C11/C12), respectively] may stabilize the structure, with centroid–centroid distance of 3.775 (6) Å.

Related literature top

For related literature, see: Khalighi et al. (2008); Ahmadi et al. (2008); Khavasi et al. (2008); Freire et al. (1999); Chen et al. (2006); Htoon & Ladd (1976).

Experimental top

For the preparation of the title compound, (I), a solution of 4,4'-dimethyl-2,2'-bipyridine (0.25 g, 1.33 mmol) in methanol (20 ml) was added to a solution of HgI₂ (0.61 g, 1.33 mmol) in acetonitrile (50 ml) and the resulting colorless solution was stirred for 20 min at room temperature, and then it was left to evaporate slowly. After one week, colorless block crystals of (I) were isolated (yield; 0.61 g, 71.8%).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SMART (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008; molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 40% probability level.
	Fig. 2. A packing diagram of the title compound.

(4,4'-Dimethyl-2,2'-bipyridine-κ²N,N')diiodidomercury(II) top

Crystal data top

[HgI₂(C₁₂H₁₂N₂)]	Z = 2
M_r = 638.63	F(000) = 568
Triclinic, P1	D_x = 2.761 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.4214 (9) Å	Cell parameters from 2145 reflections
b = 9.8391 (10) Å	θ = 2.1–29.2°
c = 10.2983 (10) Å	µ = 14.02 mm⁻¹
α = 69.383 (8)°	T = 298 K
β = 88.448 (8)°	Block, colourless
γ = 74.670 (8)°	0.38 × 0.25 × 0.12 mm
V = 768.18 (14) Å³

Data collection top

Bruker SMART CCD area-detector diffractometer	4123 independent reflections
Radiation source: fine-focus sealed tube	3467 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.091
ϕ and ω scans	θ_max = 29.2°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1998)	h = −11→11
T_min = 0.022, T_max = 0.183	k = −13→13
8874 measured reflections	l = −14→14

Refinement top

Refinement on F²	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.048	H-atom parameters constrained
wR(F²) = 0.159	w = 1/[σ²(F_o²) + (0.108P)² + 1.3499P] where P = (F_o² + 2F_c²)/3
S = 0.95	(Δ/σ)_max = 0.002
4123 reflections	Δρ_max = 1.95 e Å⁻³
155 parameters	Δρ_min = −1.38 e Å⁻³
0 restraints	Extinction correction: SHELXTL (Sheldrick, 1998), Fc^*=kFc[1+0.001xFc²λ³/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.0071 (13)

Crystal data top

[HgI₂(C₁₂H₁₂N₂)]	γ = 74.670 (8)°
M_r = 638.63	V = 768.18 (14) Å³
Triclinic, P1	Z = 2
a = 8.4214 (9) Å	Mo Kα radiation
b = 9.8391 (10) Å	µ = 14.02 mm⁻¹
c = 10.2983 (10) Å	T = 298 K
α = 69.383 (8)°	0.38 × 0.25 × 0.12 mm
β = 88.448 (8)°

Data collection top

Bruker SMART CCD area-detector diffractometer	4123 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 1998)	3467 reflections with I > 2σ(I)
T_min = 0.022, T_max = 0.183	R_int = 0.091
8874 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.048	0 restraints
wR(F²) = 0.159	H-atom parameters constrained
S = 0.95	Δρ_max = 1.95 e Å⁻³
4123 reflections	Δρ_min = −1.38 e Å⁻³
155 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

	x	y	z	U_iso*/U_eq
Hg1	0.31760 (5)	0.15247 (5)	0.30109 (4)	0.05970 (19)
I1	0.03155 (9)	0.31134 (10)	0.35551 (9)	0.0704 (2)
I2	0.63357 (8)	0.13618 (9)	0.35681 (7)	0.0594 (2)
N1	0.3481 (10)	0.2223 (10)	0.0514 (8)	0.0520 (16)
N2	0.2438 (12)	−0.0160 (12)	0.2073 (9)	0.0595 (19)
C1	0.3943 (12)	0.3461 (12)	−0.0232 (12)	0.058 (2)
H1	0.4209	0.4042	0.0227	0.069*
C2	0.4037 (14)	0.3905 (12)	−0.1657 (13)	0.064 (3)
H2	0.4374	0.4763	−0.2141	0.077*
C3	0.3630 (12)	0.3066 (10)	−0.2355 (10)	0.053 (2)
C4	0.368 (2)	0.3537 (19)	−0.3901 (13)	0.080 (4)
H4A	0.2607	0.3701	−0.4313	0.096*
H4B	0.4460	0.2758	−0.4127	0.096*
H4C	0.4015	0.4454	−0.4256	0.096*
C5	0.3166 (12)	0.1780 (10)	−0.1574 (9)	0.0512 (18)
H5	0.2901	0.1178	−0.2009	0.061*
C6	0.3098 (10)	0.1393 (10)	−0.0149 (9)	0.0461 (16)
C7	0.2537 (10)	0.0050 (9)	0.0721 (9)	0.0438 (15)
C8	0.2150 (11)	−0.0932 (10)	0.0177 (10)	0.0488 (17)
H8	0.2260	−0.0777	−0.0762	0.059*
C9	0.1602 (11)	−0.2137 (10)	0.1003 (11)	0.0525 (19)
C10	0.1200 (14)	−0.3201 (12)	0.0393 (13)	0.065 (2)
H10A	0.2170	−0.3670	0.0034	0.079*
H10B	0.0348	−0.2648	−0.0346	0.079*
H10C	0.0825	−0.3962	0.1103	0.079*
C11	0.1411 (15)	−0.2305 (14)	0.2394 (12)	0.065 (3)
H11	0.1004	−0.3078	0.2981	0.078*
C12	0.1831 (16)	−0.1319 (15)	0.2875 (11)	0.066 (3)
H12	0.1698	−0.1438	0.3805	0.079*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Hg1	0.0532 (2)	0.0783 (3)	0.0614 (3)	−0.02592 (18)	0.01400 (15)	−0.0362 (2)
I1	0.0537 (4)	0.0824 (5)	0.0729 (4)	−0.0159 (3)	0.0167 (3)	−0.0280 (4)
I2	0.0539 (3)	0.0771 (4)	0.0543 (3)	−0.0294 (3)	0.0096 (2)	−0.0241 (3)
N1	0.056 (4)	0.058 (4)	0.049 (3)	−0.022 (3)	0.010 (3)	−0.022 (3)
N2	0.063 (5)	0.077 (5)	0.047 (4)	−0.029 (4)	0.011 (3)	−0.026 (4)
C1	0.054 (5)	0.052 (5)	0.074 (6)	−0.023 (4)	0.005 (4)	−0.025 (4)
C2	0.061 (5)	0.047 (5)	0.079 (7)	−0.021 (4)	0.010 (5)	−0.013 (4)
C3	0.054 (5)	0.044 (4)	0.056 (5)	−0.013 (3)	0.006 (4)	−0.012 (3)
C4	0.089 (9)	0.089 (9)	0.056 (5)	−0.033 (7)	0.013 (5)	−0.013 (6)
C5	0.057 (5)	0.048 (4)	0.048 (4)	−0.015 (4)	0.009 (3)	−0.016 (3)
C6	0.041 (4)	0.044 (4)	0.052 (4)	−0.011 (3)	0.013 (3)	−0.017 (3)
C7	0.039 (3)	0.042 (3)	0.048 (4)	−0.010 (3)	0.008 (3)	−0.016 (3)
C8	0.047 (4)	0.048 (4)	0.053 (4)	−0.014 (3)	0.012 (3)	−0.020 (3)
C9	0.043 (4)	0.048 (4)	0.061 (5)	−0.012 (3)	0.004 (3)	−0.014 (3)
C10	0.067 (5)	0.049 (5)	0.078 (6)	−0.014 (4)	0.010 (5)	−0.021 (4)
C11	0.071 (6)	0.070 (6)	0.060 (5)	−0.040 (5)	0.007 (5)	−0.013 (5)
C12	0.075 (7)	0.079 (7)	0.050 (4)	−0.040 (5)	0.015 (4)	−0.017 (4)

Geometric parameters (Å, º) top

Hg1—I1	2.6671 (9)	C6—N1	1.334 (12)
Hg1—I2	2.6885 (8)	C6—C7	1.498 (12)
N1—Hg1	2.442 (8)	C7—N2	1.337 (12)
N2—Hg1	2.402 (10)	C7—C8	1.383 (13)
C1—N1	1.342 (13)	C8—C9	1.378 (13)
C1—C2	1.382 (17)	C8—H8	0.9300
C1—H1	0.9300	C9—C11	1.392 (16)
C2—C3	1.377 (17)	C9—C10	1.506 (16)
C2—H2	0.9300	C10—H10A	0.9600
C3—C5	1.389 (13)	C10—H10B	0.9600
C3—C4	1.497 (16)	C10—H10C	0.9600
C4—H4A	0.9600	C11—C12	1.357 (18)
C4—H4B	0.9600	C11—H11	0.9300
C4—H4C	0.9600	C12—N2	1.366 (15)
C5—C6	1.384 (12)	C12—H12	0.9300
C5—H5	0.9300

I1—Hg1—I2	132.56 (3)	C6—C5—C3	120.2 (9)
N1—Hg1—I1	111.9 (2)	C6—C5—H5	119.7
N1—Hg1—I2	92.87 (19)	C3—C5—H5	120.2
N2—Hg1—N1	67.3 (3)	N1—C6—C5	121.6 (8)
N2—Hg1—I1	104.9 (2)	N1—C6—C7	116.6 (8)
N2—Hg1—I2	122.2 (2)	C5—C6—C7	121.7 (8)
C1—N1—Hg1	122.2 (7)	N2—C7—C8	121.2 (8)
C6—N1—Hg1	119.2 (6)	N2—C7—C6	116.1 (8)
C6—N1—C1	118.6 (8)	C8—C7—C6	122.6 (8)
C7—N2—Hg1	120.8 (7)	C9—C8—C7	121.0 (9)
C7—N2—C12	117.4 (9)	C9—C8—H8	119.4
C12—N2—Hg1	121.7 (7)	C7—C8—H8	119.6
N1—C1—C2	122.5 (10)	C8—C9—C11	117.7 (10)
N1—C1—H1	118.7	C8—C9—C10	120.2 (10)
C2—C1—H1	118.8	C11—C9—C10	122.1 (9)
C3—C2—C1	119.5 (10)	C9—C10—H10A	109.2
C3—C2—H2	120.1	C9—C10—H10B	109.6
C1—C2—H2	120.4	H10A—C10—H10B	109.5
C2—C3—C5	117.6 (10)	C9—C10—H10C	109.6
C2—C3—C4	120.8 (11)	H10A—C10—H10C	109.5
C5—C3—C4	121.6 (11)	H10B—C10—H10C	109.5
C3—C4—H4A	109.3	C12—C11—C9	118.7 (10)
C3—C4—H4B	109.5	C12—C11—H11	120.7
H4A—C4—H4B	109.5	C9—C11—H11	120.6
C3—C4—H4C	109.6	N2—C12—C11	123.8 (10)
H4A—C4—H4C	109.5	N2—C12—H12	118.1
H4B—C4—H4C	109.5	C11—C12—H12	118.2

C1—N1—Hg1—I1	79.7 (8)	C5—C6—N1—Hg1	176.7 (6)
C1—N1—Hg1—I2	−58.9 (7)	C7—C6—N1—Hg1	−1.4 (10)
C1—N1—Hg1—N2	177.2 (8)	C5—C6—N1—C1	−0.1 (13)
C6—N1—Hg1—I1	−96.9 (7)	C7—C6—N1—C1	−178.1 (8)
C6—N1—Hg1—I2	124.5 (7)	N1—C6—C7—N2	1.6 (11)
C6—N1—Hg1—N2	0.6 (7)	C5—C6—C7—N2	−176.5 (9)
C7—N2—Hg1—I1	108.1 (7)	N1—C6—C7—C8	−178.0 (8)
C7—N2—Hg1—I2	−78.2 (8)	C5—C6—C7—C8	4.0 (12)
C7—N2—Hg1—N1	0.2 (7)	C6—C7—N2—Hg1	−1.0 (10)
C12—N2—Hg1—I1	−68.7 (9)	C8—C7—N2—Hg1	178.6 (6)
C12—N2—Hg1—I2	104.9 (9)	C6—C7—N2—C12	176.0 (9)
C12—N2—Hg1—N1	−176.6 (10)	C8—C7—N2—C12	−4.5 (14)
C2—C1—N1—C6	−0.1 (15)	N2—C7—C8—C9	1.9 (13)
C2—C1—N1—Hg1	−176.7 (8)	C6—C7—C8—C9	−178.6 (8)
N1—C1—C2—C3	0.7 (16)	C7—C8—C9—C11	1.7 (13)
C1—C2—C3—C5	−1.2 (16)	C7—C8—C9—C10	−179.5 (8)
C1—C2—C3—C4	178.6 (11)	C8—C9—C11—C12	−2.5 (16)
C2—C3—C5—C6	1.1 (14)	C10—C9—C11—C12	178.7 (11)
C4—C3—C5—C6	−178.7 (10)	C9—C11—C12—N2	−0.1 (19)
C3—C5—C6—N1	−0.5 (14)	C11—C12—N2—Hg1	−179.4 (10)
C3—C5—C6—C7	177.4 (8)	C11—C12—N2—C7	3.6 (18)

Experimental details

Crystal data
Chemical formula	[HgI₂(C₁₂H₁₂N₂)]
M_r	638.63
Crystal system, space group	Triclinic, P1
Temperature (K)	298
a, b, c (Å)	8.4214 (9), 9.8391 (10), 10.2983 (10)
α, β, γ (°)	69.383 (8), 88.448 (8), 74.670 (8)
V (Å³)	768.18 (14)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	14.02
Crystal size (mm)	0.38 × 0.25 × 0.12

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 1998)
T_min, T_max	0.022, 0.183
No. of measured, independent and observed [I > 2σ(I)] reflections	8874, 4123, 3467
R_int	0.091
(sin θ/λ)_max (Å⁻¹)	0.686

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.048, 0.159, 0.95
No. of reflections	4123
No. of parameters	155
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.95, −1.38

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SHELXTL (Sheldrick, 2008), SHELXTL (Sheldrick, 2008, ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Selected geometric parameters (Å, º) top

Hg1—I1	2.6671 (9)	N1—Hg1	2.442 (8)
Hg1—I2	2.6885 (8)	N2—Hg1	2.402 (10)

I1—Hg1—I2	132.56 (3)	N2—Hg1—N1	67.3 (3)
N1—Hg1—I1	111.9 (2)	N2—Hg1—I1	104.9 (2)
N1—Hg1—I2	92.87 (19)	N2—Hg1—I2	122.2 (2)

Acknowledgements

We are grateful to the Islamic Azad University, Shahr-e-Rey Branch, for financial support.

References

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