Di-μ-chlorido-bis­({2-[(4-bromo­phen­yl)­imino­meth­yl]pyridine-κ2N,N′}­chloridomercury(II))

Mahmoudi, A.; Dehghanpour, S.; Khalaj, M.; Pakravan, S.

doi:10.1107/S1600536809025641

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 8| August 2009| Page m889

doi:10.1107/S1600536809025641

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Di-μ-chlorido-bis({2-[(4-bromophenyl)iminomethyl]pyridine-κ²N,N′}chloridomercury(II))

Ali Mahmoudi,^a ^* Saeed Dehghanpour,^b Mehdi Khalaj ^c and Shabnam Pakravan ^a

^aDepartment of Chemistry, Islamic Azad University, Karaj Branch, Karaj, Iran, ^bDepartment of Chemistry, Alzahra University, PO Box 1993891176, Vanak, Tehran, Iran, and ^cDepartment of Chemistry, Islamic Azad University, Buinzahra Branch, Qazvin, Iran
^*Correspondence e-mail: Mahmoudi_Ali@yahoo.com

(Received 11 June 2009; accepted 2 July 2009; online 11 July 2009)

The unique Hg^II ion in the title centrosymmetric dinuclear complex, [Hg₂Cl₄(C₁₂H₉BrN₂)₂], is in a distorted trigonal–bipyramidal coordination environment formed by the bis-chelating N-heterocyclic ligand, two bridging Cl atoms and one terminal Cl atom. One of the bridging Hg—Cl bonds is significantly longer than the other.

Related literature

For background information on diimine complexes, see: Dehghanpour & Mahmoudi (2007 ); Dehghanpour, Mahmoudi, Khalaj & Salmanpour (2007 ). For related crystal structures, see: Mahmoudi et al. (2009 ); Dehghanpour, Mahmoudi, Khalaj, Salmanpour & Adib (2007 ).

Experimental

Crystal data

[Hg₂Cl₄(C₁₂H₉BrN₂)₂]
M_r = 1065.22
Monoclinic, P 2₁ /n
a = 7.6697 (2) Å
b = 15.0247 (4) Å
c = 12.2129 (4) Å
β = 96.738 (1)°
V = 1397.63 (7) Å³
Z = 2
Mo Kα radiation
μ = 14.24 mm⁻¹
T = 100 K
0.10 × 0.10 × 0.05 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (APEX2; Bruker, 2005 ) T_min = 0.280, T_max = 0.491
17922 measured reflections
4047 independent reflections
3636 reflections with I > 2σ(I)
R_int = 0.032

Refinement

R[F² > 2σ(F²)] = 0.019
wR(F²) = 0.041
S = 1.01
4047 reflections
163 parameters
H-atom parameters constrained
Δρ_max = 0.97 e Å⁻³
Δρ_min = −1.15 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Hg1—N2	2.318 (2)
Hg1—Cl1	2.3799 (7)
Hg1—N1	2.472 (2)
Hg1—Cl2	2.4941 (7)
Hg1—Cl2ⁱ	2.8799 (6)

N2—Hg1—Cl1	129.00 (6)
N2—Hg1—N1	70.58 (7)
Cl1—Hg1—N1	107.12 (5)
N2—Hg1—Cl2	102.20 (6)
Cl1—Hg1—Cl2	128.74 (3)
N1—Hg1—Cl2	90.35 (5)
N2—Hg1—Cl2ⁱ	88.36 (6)
Cl1—Hg1—Cl2ⁱ	90.07 (2)
N1—Hg1—Cl2ⁱ	158.28 (5)
Cl2—Hg1—Cl2ⁱ	88.926 (19)
Hg1—Cl2—Hg1ⁱ	91.074 (19)
Symmetry code: (i) -x, -y+1, -z.

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2; data reduction: APEX2; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: PLATON (Spek, 2009 ); software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809025641/lh2844sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809025641/lh2844Isup2.hkl

checkCIF report

Comment top

In our ongoing studies on the synthesis, structural and spectroscopic characterization of transition metal complexes with diimine ligands (Dehghanpour & Mahmoudi, 2007; Dehghanpour, Mahmoudi, Khalaj, Salmanpour & Adib (2007), we report herein the crystal structure of the title complex. The title compound was prepared by the reaction of HgCl₂ with (4-bromophenyl)pyridin-2-ylmethyleneamine.

The molecluar structure of the title complex (I) is shown in (Fig. 1). The unique Hg^II ion in is in a distorted trigonal-bipyramidal coordination environment formed by a bis-chelating ligand, two bridging Cl atoms and one terminal Cl atom. One of the bridging Hg-Cl bonds is significantly longer than the other.

Related literature top

For background information on diimine complexes, see: Dehghanpour & Mahmoudi (2007); Dehghanpour, Mahmoudi, Khalaj & Salmanpour (2007). For related crystal structures, see: Mahmoudi et al. (2009); Dehghanpour, Mahmoudi, Khalaj, Salmanpour & Adib (2007).

Experimental top

The title complex was prepared by the reaction of HgCl₂ and (4-bromophenyl)pyridin-2-ylmethyleneamine (molar ratio 1:1) in acetonitrile at room temperature. The solution was then concentrated under vacuum, and diffusion of diethyl ether vapor into the concentrated solution gave yellow crystals of (I) in 69% yield. Calc. for C₁₂H₉BrCl₂HgN₂: C 27.06, H 1.70, N 5.26%; found: C 27.01, H 1.72, N 5.20%.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: APEX2 (Bruker, 2005); data reduction: APEX2 (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

Fig. 1. The molecular structure od the title complex, with displacement ellipsoids drawn at the 50% probability level. H atoms are represented as spheres of arbitrary radius [symmetry code: (a) -x, -y+1, -z].

Di-µ-chlorido-bis({2-[(4-bromophenyl)iminomethyl]pyridine- κ²N,N'}chloridomercury(II)) top

Crystal data top

[Hg₂Cl₄(C₁₂H₉BrN₂)₂]	F(000) = 976
M_r = 1065.22	D_x = 2.531 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 8129 reflections
a = 7.6697 (2) Å	θ = 2.2–29.7°
b = 15.0247 (4) Å	µ = 14.24 mm⁻¹
c = 12.2129 (4) Å	T = 100 K
β = 96.738 (1)°	Prism, yellow
V = 1397.63 (7) Å³	0.10 × 0.10 × 0.05 mm
Z = 2

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	4047 independent reflections
Radiation source: fine-focus sealed tube	3636 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.032
Detector resolution: 0 pixels mm^-1	θ_max = 30.0°, θ_min = 2.2°
ϕ and ω scans	h = −10→10
Absorption correction: multi-scan (APEX2; Bruker, 2005)	k = −21→20
T_min = 0.280, T_max = 0.491	l = −17→17
17922 measured reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.019	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.041	H-atom parameters constrained
S = 1.01	w = 1/[σ²(F_o²) + (0.015P)² + 1.35P] where P = (F_o² + 2F_c²)/3
4047 reflections	(Δ/σ)_max = 0.001
163 parameters	Δρ_max = 0.97 e Å⁻³
0 restraints	Δρ_min = −1.15 e Å⁻³

Crystal data top

[Hg₂Cl₄(C₁₂H₉BrN₂)₂]	V = 1397.63 (7) Å³
M_r = 1065.22	Z = 2
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.6697 (2) Å	µ = 14.24 mm⁻¹
b = 15.0247 (4) Å	T = 100 K
c = 12.2129 (4) Å	0.10 × 0.10 × 0.05 mm
β = 96.738 (1)°

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	4047 independent reflections
Absorption correction: multi-scan (APEX2; Bruker, 2005)	3636 reflections with I > 2σ(I)
T_min = 0.280, T_max = 0.491	R_int = 0.032
17922 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.019	0 restraints
wR(F²) = 0.041	H-atom parameters constrained
S = 1.01	Δρ_max = 0.97 e Å⁻³
4047 reflections	Δρ_min = −1.15 e Å⁻³
163 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	0.170956 (13)	0.446982 (7)	0.108289 (9)	0.02080 (3)
Br1	0.86964 (5)	0.10383 (2)	−0.01114 (3)	0.04340 (9)
Cl1	0.42148 (9)	0.53787 (4)	0.15929 (7)	0.03126 (16)
Cl2	0.04621 (9)	0.39647 (4)	−0.07921 (5)	0.02143 (12)
N1	0.2551 (3)	0.29234 (14)	0.15931 (18)	0.0183 (4)
N2	−0.0272 (3)	0.38863 (15)	0.21855 (18)	0.0192 (4)
C1	−0.0010 (3)	0.30362 (17)	0.2535 (2)	0.0192 (5)
C2	−0.1169 (4)	0.26078 (18)	0.3146 (2)	0.0207 (5)
H2A	−0.0974	0.2006	0.3366	0.025*
C3	−0.2618 (4)	0.30668 (18)	0.3433 (2)	0.0219 (5)
H3A	−0.3420	0.2788	0.3861	0.026*
C4	−0.2871 (4)	0.39390 (18)	0.3083 (2)	0.0218 (5)
H4A	−0.3842	0.4272	0.3275	0.026*
C5	−0.1679 (4)	0.43198 (18)	0.2445 (2)	0.0209 (5)
H5A	−0.1878	0.4911	0.2184	0.025*
C6	0.1522 (4)	0.25556 (18)	0.2214 (2)	0.0212 (5)
H6A	0.1752	0.1965	0.2471	0.025*
C7	0.3966 (3)	0.24488 (18)	0.1221 (2)	0.0194 (5)
C8	0.4078 (4)	0.15213 (19)	0.1228 (2)	0.0239 (5)
H8A	0.3193	0.1175	0.1508	0.029*
C9	0.5489 (4)	0.1107 (2)	0.0824 (2)	0.0270 (6)
H9A	0.5572	0.0476	0.0820	0.032*
C10	0.6778 (4)	0.1622 (2)	0.0425 (2)	0.0260 (6)
C11	0.6691 (4)	0.25420 (19)	0.0398 (2)	0.0230 (5)
H11A	0.7587	0.2884	0.0122	0.028*
C12	0.5255 (3)	0.29538 (18)	0.0786 (2)	0.0206 (5)
H12A	0.5151	0.3584	0.0756	0.025*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Hg1	0.02163 (5)	0.01490 (5)	0.02590 (6)	−0.00157 (4)	0.00290 (4)	0.00198 (4)
Br1	0.04489 (19)	0.03626 (17)	0.0548 (2)	0.01823 (15)	0.03004 (17)	0.01083 (16)
Cl1	0.0233 (3)	0.0157 (3)	0.0531 (5)	−0.0016 (2)	−0.0027 (3)	−0.0017 (3)
Cl2	0.0274 (3)	0.0159 (3)	0.0210 (3)	0.0040 (2)	0.0029 (2)	0.0000 (2)
N1	0.0210 (10)	0.0147 (10)	0.0187 (10)	0.0018 (8)	0.0009 (8)	−0.0002 (8)
N2	0.0221 (10)	0.0163 (10)	0.0194 (10)	−0.0008 (8)	0.0028 (8)	0.0005 (8)
C1	0.0227 (12)	0.0171 (12)	0.0179 (12)	0.0002 (9)	0.0025 (10)	0.0003 (9)
C2	0.0278 (13)	0.0152 (12)	0.0189 (12)	−0.0014 (10)	0.0027 (10)	0.0027 (9)
C3	0.0248 (13)	0.0226 (13)	0.0188 (12)	−0.0017 (10)	0.0043 (10)	0.0028 (10)
C4	0.0234 (12)	0.0201 (12)	0.0221 (13)	0.0042 (10)	0.0034 (10)	0.0019 (10)
C5	0.0256 (13)	0.0170 (12)	0.0203 (12)	0.0028 (10)	0.0030 (10)	0.0031 (10)
C6	0.0271 (13)	0.0162 (12)	0.0202 (12)	0.0018 (10)	0.0030 (10)	0.0014 (10)
C7	0.0201 (11)	0.0202 (12)	0.0175 (12)	0.0025 (10)	0.0004 (9)	0.0005 (10)
C8	0.0281 (13)	0.0203 (13)	0.0244 (13)	0.0015 (11)	0.0071 (11)	0.0030 (11)
C9	0.0365 (15)	0.0199 (13)	0.0258 (14)	0.0089 (11)	0.0086 (12)	0.0027 (11)
C10	0.0283 (13)	0.0273 (14)	0.0236 (13)	0.0088 (11)	0.0077 (11)	0.0036 (11)
C11	0.0231 (12)	0.0252 (13)	0.0209 (12)	0.0008 (11)	0.0038 (10)	0.0014 (11)
C12	0.0225 (12)	0.0204 (12)	0.0187 (12)	0.0003 (10)	0.0017 (10)	0.0011 (10)

Geometric parameters (Å, º) top

Hg1—N2	2.318 (2)	C3—H3A	0.9500
Hg1—Cl1	2.3799 (7)	C4—C5	1.392 (4)
Hg1—N1	2.472 (2)	C4—H4A	0.9500
Hg1—Cl2	2.4941 (7)	C5—H5A	0.9500
Hg1—Cl2ⁱ	2.8799 (6)	C6—H6A	0.9500
Br1—C10	1.894 (3)	C7—C8	1.396 (4)
Cl2—Hg1ⁱ	2.8799 (6)	C7—C12	1.399 (4)
N1—C6	1.282 (3)	C8—C9	1.389 (4)
N1—C7	1.418 (3)	C8—H8A	0.9500
N2—C5	1.330 (3)	C9—C10	1.388 (4)
N2—C1	1.354 (3)	C9—H9A	0.9500
C1—C2	1.384 (4)	C10—C11	1.385 (4)
C1—C6	1.471 (4)	C11—C12	1.394 (4)
C2—C3	1.387 (4)	C11—H11A	0.9500
C2—H2A	0.9500	C12—H12A	0.9500
C3—C4	1.385 (4)

N2—Hg1—Cl1	129.00 (6)	C3—C4—H4A	120.5
N2—Hg1—N1	70.58 (7)	C5—C4—H4A	120.5
Cl1—Hg1—N1	107.12 (5)	N2—C5—C4	122.4 (2)
N2—Hg1—Cl2	102.20 (6)	N2—C5—H5A	118.8
Cl1—Hg1—Cl2	128.74 (3)	C4—C5—H5A	118.8
N1—Hg1—Cl2	90.35 (5)	N1—C6—C1	120.8 (2)
N2—Hg1—Cl2ⁱ	88.36 (6)	N1—C6—H6A	119.6
Cl1—Hg1—Cl2ⁱ	90.07 (2)	C1—C6—H6A	119.6
N1—Hg1—Cl2ⁱ	158.28 (5)	C8—C7—C12	119.9 (2)
Cl2—Hg1—Cl2ⁱ	88.926 (19)	C8—C7—N1	123.3 (2)
Hg1—Cl2—Hg1ⁱ	91.074 (19)	C12—C7—N1	116.8 (2)
C6—N1—C7	121.4 (2)	C9—C8—C7	119.7 (3)
C6—N1—Hg1	113.18 (17)	C9—C8—H8A	120.2
C7—N1—Hg1	125.39 (17)	C7—C8—H8A	120.2
C5—N2—C1	118.8 (2)	C10—C9—C8	119.4 (3)
C5—N2—Hg1	123.96 (18)	C10—C9—H9A	120.3
C1—N2—Hg1	117.19 (17)	C8—C9—H9A	120.3
N2—C1—C2	121.8 (2)	C11—C10—C9	122.1 (3)
N2—C1—C6	118.2 (2)	C11—C10—Br1	119.4 (2)
C2—C1—C6	119.9 (2)	C9—C10—Br1	118.5 (2)
C1—C2—C3	119.3 (2)	C10—C11—C12	118.2 (3)
C1—C2—H2A	120.4	C10—C11—H11A	120.9
C3—C2—H2A	120.4	C12—C11—H11A	120.9
C4—C3—C2	118.6 (2)	C11—C12—C7	120.7 (3)
C4—C3—H3A	120.7	C11—C12—H12A	119.7
C2—C3—H3A	120.7	C7—C12—H12A	119.7
C3—C4—C5	119.0 (2)

N2—Hg1—Cl2—Hg1ⁱ	88.09 (6)	C6—C1—C2—C3	−179.4 (2)
Cl1—Hg1—Cl2—Hg1ⁱ	−89.22 (3)	C1—C2—C3—C4	0.9 (4)
N1—Hg1—Cl2—Hg1ⁱ	158.29 (5)	C2—C3—C4—C5	0.8 (4)
Cl2ⁱ—Hg1—Cl2—Hg1ⁱ	0.0	C1—N2—C5—C4	1.5 (4)
N2—Hg1—N1—C6	−0.60 (18)	Hg1—N2—C5—C4	178.0 (2)
Cl1—Hg1—N1—C6	125.53 (18)	C3—C4—C5—N2	−2.1 (4)
Cl2—Hg1—N1—C6	−103.42 (18)	C7—N1—C6—C1	−175.9 (2)
Cl2ⁱ—Hg1—N1—C6	−15.4 (3)	Hg1—N1—C6—C1	1.6 (3)
N2—Hg1—N1—C7	176.8 (2)	N2—C1—C6—N1	−2.1 (4)
Cl1—Hg1—N1—C7	−57.1 (2)	C2—C1—C6—N1	175.8 (3)
Cl2—Hg1—N1—C7	73.94 (19)	C6—N1—C7—C8	18.2 (4)
Cl2ⁱ—Hg1—N1—C7	161.92 (14)	Hg1—N1—C7—C8	−159.0 (2)
Cl1—Hg1—N2—C5	86.3 (2)	C6—N1—C7—C12	−164.6 (2)
N1—Hg1—N2—C5	−177.1 (2)	Hg1—N1—C7—C12	18.3 (3)
Cl2—Hg1—N2—C5	−91.0 (2)	C12—C7—C8—C9	1.3 (4)
Cl2ⁱ—Hg1—N2—C5	−2.5 (2)	N1—C7—C8—C9	178.5 (3)
Cl1—Hg1—N2—C1	−97.14 (19)	C7—C8—C9—C10	0.5 (4)
N1—Hg1—N2—C1	−0.46 (18)	C8—C9—C10—C11	−1.1 (5)
Cl2—Hg1—N2—C1	85.56 (18)	C8—C9—C10—Br1	179.6 (2)
Cl2ⁱ—Hg1—N2—C1	174.10 (18)	C9—C10—C11—C12	0.0 (4)
C5—N2—C1—C2	0.4 (4)	Br1—C10—C11—C12	179.3 (2)
Hg1—N2—C1—C2	−176.4 (2)	C10—C11—C12—C7	1.8 (4)
C5—N2—C1—C6	178.2 (2)	C8—C7—C12—C11	−2.5 (4)
Hg1—N2—C1—C6	1.4 (3)	N1—C7—C12—C11	−179.8 (2)
N2—C1—C2—C3	−1.6 (4)

Symmetry code: (i) −x, −y+1, −z.

Experimental details

Crystal data
Chemical formula	[Hg₂Cl₄(C₁₂H₉BrN₂)₂]
M_r	1065.22
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	100
a, b, c (Å)	7.6697 (2), 15.0247 (4), 12.2129 (4)
β (°)	96.738 (1)
V (Å³)	1397.63 (7)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	14.24
Crystal size (mm)	0.10 × 0.10 × 0.05

Data collection
Diffractometer	Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (APEX2; Bruker, 2005)
T_min, T_max	0.280, 0.491
No. of measured, independent and observed [I > 2σ(I)] reflections	17922, 4047, 3636
R_int	0.032
(sin θ/λ)_max (Å⁻¹)	0.703

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.019, 0.041, 1.01
No. of reflections	4047
No. of parameters	163
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.97, −1.15

Computer programs: APEX2 (Bruker, 2005), SHELXTL (Sheldrick, 2008), PLATON (Spek, 2009).

Selected geometric parameters (Å, º) top

Hg1—N2	2.318 (2)	Hg1—Cl2	2.4941 (7)
Hg1—Cl1	2.3799 (7)	Hg1—Cl2ⁱ	2.8799 (6)
Hg1—N1	2.472 (2)

N2—Hg1—Cl1	129.00 (6)	N2—Hg1—Cl2ⁱ	88.36 (6)
N2—Hg1—N1	70.58 (7)	Cl1—Hg1—Cl2ⁱ	90.07 (2)
Cl1—Hg1—N1	107.12 (5)	N1—Hg1—Cl2ⁱ	158.28 (5)
N2—Hg1—Cl2	102.20 (6)	Cl2—Hg1—Cl2ⁱ	88.926 (19)
Cl1—Hg1—Cl2	128.74 (3)	Hg1—Cl2—Hg1ⁱ	91.074 (19)
N1—Hg1—Cl2	90.35 (5)

Symmetry code: (i) −x, −y+1, −z.

Acknowledgements

AM acknowledges the Islamic Azad University Research Council for partial support of this work.

References

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