Dibromido(6-methyl-2,2′-bipyridine-κ2N,N′)zinc(II)

Kalateh, K.; Ahmadi, R.; Amani, V.

doi:10.1107/S1600536810035658

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 10| October 2010| Page m1241

doi:10.1107/S1600536810035658

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Dibromido(6-methyl-2,2′-bipyridine-κ²N,N′)zinc(II)

Khadijeh Kalateh,^a Roya Ahmadi ^a and Vahid Amani ^a ^*

^aIslamic Azad University, Shahr-e-Rey Branch, Tehran, Iran
^*Correspondence e-mail: v_amani2002@yahoo.com

(Received 15 June 2010; accepted 5 September 2010; online 11 September 2010)

In the title compound, [ZnBr₂(C₁₁H₁₀N₂)], the Zn^II atom is four-coordinated in a distorted tetrahedral configuration by two N atoms from a 6-methyl-2,2′-bipyridine ligand and two terminal Br atoms. Weak intermolecular C—H⋯Br hydrogen bonds and π–π stacking interactions between the pyridine rings [centroid–centroid distances = 3.763 (5) and 3.835 (6) Å] contribute to crystal-packing effects.

Related literature

For unusual coordination geometries on transition metal atoms, see: Beeston et al. (1998 ), Meyer et al. (1999 ); For related literature, see: Ahmadi et al. (2009 ); Ahmadi, Ebadi et al. (2008 ); Ahmadi, Kalateh et al. (2008 ); Alizadeh et al. (2009 ); Amani et al. (2009 ); Newkome et al. (1982 ); Onggo et al. (1990 , 2005 ).

Experimental

Crystal data

[ZnBr₂(C₁₁H₁₀N₂)]
M_r = 395.40
Monoclinic, P 2₁ /n
a = 7.6445 (7) Å
b = 9.7487 (11) Å
c = 17.8347 (18) Å
β = 96.972 (8)°
V = 1319.3 (2) Å³
Z = 4
Mo Kα radiation
μ = 7.89 mm⁻¹
T = 298 K
0.46 × 0.30 × 0.15 mm

Data collection

Bruker SMART CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2003 ) T_min = 0.076, T_max = 0.310
15389 measured reflections
3567 independent reflections
2498 reflections with I > 2σ(I)
R_int = 0.119

Refinement

R[F² > 2σ(F²)] = 0.086
wR(F²) = 0.207
S = 1.13
3567 reflections
145 parameters
H-atom parameters constrained
Δρ_max = 2.14 e Å⁻³
Δρ_min = −1.14 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1C⋯Br1ⁱ	0.96	2.86	3.805 (14)	169
C8—H8⋯Br1ⁱⁱ	0.93	2.93	3.812 (12)	159
Symmetry codes: (i) $[-x+{\script{3\over 2}}, y+{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (ii) -x+2, -y+2, -z.

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 (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810035658/jj2041sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536810035658/jj2041Isup2.hkl

checkCIF report

Comment top

Sterically hindered ligands such as 6-Methyl-2, 2'-bipyridine (6-mbipy) often convey unusual coordination geometries or oxidation states on transition metal centers (Beeston et al., 1998; Meyer et al. 1999). Numerous complexes with 6-mbipy have been prepared, such as that of mercury (Ahmadi, Ebadi et al., 2008), platin (Amani et al., 2009), lead (Ahmadi et al., 2009), palladium (Newkome et al., 1982), ruthenium (Onggo, Scudder et al., 2005) and iron (Onggo, Hook et al., 1990). Here, we report the synthesis and structure of the title compound, [Zn(C₁₁H₁₀N₂)Br₂].

In the title compound (Fig. 1), the Zn^II atom is four-coordinated in a distorted tetrahedral configuration by two N atoms from one 6-methyl-2,2'-bipyridine and two terminal Br atoms. The Zn—N and Zn—Br bond lengths and angles are within the normal range of [ZnCl₂(6-mbpy)], (Ahmadi, Kalateh et al., 2008) and [ZnBr₂(6,6'-dmbpy)], (Alizadeh et al., 2009) [where 6,6'-dmbpy is 6,6'-dimethyl-2, 2'-bipyridine] respectively.

In the crystal structure, weak intermolecular C—H···Br hydrogen bonds (Table 2) and π···π stacking interactions (Fig. 2, Table 1) between the pyridine rings,Cg1—Cg2 and Cg2—Cg3 contribute to crystal packing effects [where Cg1, Cg2 and Cg3 are centroids of the rings (Zn1/N1/C6—C7/N2), (N1/C2—C6) and (N2/C7—C11), respectively].

Related literature top

For unusual coordination geometries on transition metal centers, see: (Beeston et al. (1998), Meyer et al. (1999); For related literature, see: Ahmadi et al. (2009); Ahmadi, Ebadi, et al. (2008); Ahmadi, Kalateh, et al. (2008); Alizadeh et al. (2009); Amani et al. (2009); Newkome et al. (1982); Onggo et al. (1990, 2005).

Experimental top

For the preparation of the title compound, a solution of 6-methyl-2,2'-bipyridine (0.16 g, 0.15 ml 0.94 mmol) in methanol (10 ml) was added to a solution of ZnBr₂ (0.21 g, 0.94 mmol) in acetonitrile (30 ml) and the resulting colorless solution was stirred for 20 min at 313 K. This solution was left to evaporate slowly at room temperature. After one week, colorless prismatic crystals of the title compound were isolated (yield 0.28 g, 75.3%).

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (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 (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. The molecular structure of the title molecule, [Zn(C₁₁H₁₀N₂)Br₂], with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.
	Fig. 2. Unit-cell packing diagram for [Zn(C₁₁H₁₀N₂)Br₂]. Dashed lines indicate weak C—H···Br intermolecular interactions.

Dibromido(6-methyl-2,2'-bipyridine-κ²N,N')zinc(II) top

Crystal data top

[ZnBr₂(C₁₁H₁₀N₂)]	F(000) = 760
M_r = 395.40	D_x = 1.991 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 985 reflections
a = 7.6445 (7) Å	θ = 2.3–29.4°
b = 9.7487 (11) Å	µ = 7.89 mm⁻¹
c = 17.8347 (18) Å	T = 298 K
β = 96.972 (8)°	Prism, colorless
V = 1319.3 (2) Å³	0.46 × 0.30 × 0.15 mm
Z = 4

Data collection top

Bruker SMART CCD area-detector diffractometer	3567 independent reflections
Radiation source: fine-focus sealed tube	2498 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.119
ϕ and ω scans	θ_max = 29.4°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	h = −8→10
T_min = 0.076, T_max = 0.310	k = −13→13
15389 measured reflections	l = −24→24

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)] = 0.086	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.207	H-atom parameters constrained
S = 1.13	w = 1/[σ²(F_o²) + (0.0565P)² + 8.4252P] where P = (F_o² + 2F_c²)/3
3567 reflections	(Δ/σ)_max = 0.002
145 parameters	Δρ_max = 2.14 e Å⁻³
0 restraints	Δρ_min = −1.14 e Å⁻³

Crystal data top

[ZnBr₂(C₁₁H₁₀N₂)]	V = 1319.3 (2) Å³
M_r = 395.40	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.6445 (7) Å	µ = 7.89 mm⁻¹
b = 9.7487 (11) Å	T = 298 K
c = 17.8347 (18) Å	0.46 × 0.30 × 0.15 mm
β = 96.972 (8)°

Data collection top

Bruker SMART CCD area-detector diffractometer	3567 independent reflections
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	2498 reflections with I > 2σ(I)
T_min = 0.076, T_max = 0.310	R_int = 0.119
15389 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.086	0 restraints
wR(F²) = 0.207	H-atom parameters constrained
S = 1.13	Δρ_max = 2.14 e Å⁻³
3567 reflections	Δρ_min = −1.14 e Å⁻³
145 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
C1	0.651 (2)	0.9482 (15)	0.2106 (6)	0.099 (5)
H1A	0.7590	0.9042	0.2302	0.119*
H1B	0.5594	0.8805	0.2012	0.119*
H1C	0.6183	1.0135	0.2468	0.119*
C2	0.6740 (14)	1.0200 (10)	0.1390 (6)	0.063 (2)
C3	0.6519 (15)	1.1604 (12)	0.1292 (7)	0.074 (3)
H3	0.6227	1.2153	0.1685	0.089*
C4	0.6738 (15)	1.2162 (11)	0.0608 (8)	0.075 (3)
H4	0.6559	1.3097	0.0527	0.090*
C5	0.7221 (13)	1.1355 (10)	0.0041 (6)	0.063 (2)
H5	0.7415	1.1739	−0.0419	0.076*
C6	0.7415 (11)	0.9971 (9)	0.0160 (5)	0.051 (2)
C7	0.7873 (11)	0.8977 (10)	−0.0412 (5)	0.0509 (19)
C8	0.8184 (14)	0.9373 (12)	−0.1129 (6)	0.070 (3)
H8	0.8168	1.0293	−0.1268	0.084*
C9	0.8523 (16)	0.8339 (15)	−0.1639 (6)	0.080 (3)
H9	0.8735	0.8568	−0.2126	0.096*
C10	0.8542 (18)	0.7025 (14)	−0.1426 (6)	0.080 (3)
H10	0.8736	0.6339	−0.1768	0.097*
C11	0.8280 (15)	0.6692 (12)	−0.0710 (6)	0.072 (3)
H11	0.8344	0.5776	−0.0563	0.087*
N1	0.7182 (10)	0.9406 (7)	0.0849 (4)	0.0508 (17)
N2	0.7930 (10)	0.7647 (8)	−0.0208 (4)	0.0530 (17)
Br1	1.04853 (15)	0.69883 (13)	0.15998 (7)	0.0756 (4)
Br2	0.54078 (15)	0.58954 (13)	0.11809 (7)	0.0767 (4)
Zn1	0.76827 (14)	0.73342 (11)	0.09099 (6)	0.0525 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.147 (13)	0.102 (10)	0.056 (6)	0.016 (9)	0.040 (8)	−0.011 (6)
C2	0.063 (6)	0.057 (5)	0.068 (6)	0.004 (5)	0.010 (5)	−0.004 (5)
C3	0.061 (6)	0.070 (7)	0.088 (8)	0.006 (5)	0.001 (5)	−0.018 (6)
C4	0.071 (7)	0.051 (5)	0.102 (9)	0.003 (5)	0.005 (6)	0.013 (6)
C5	0.063 (6)	0.056 (5)	0.070 (6)	0.003 (5)	0.008 (5)	0.015 (5)
C6	0.038 (4)	0.058 (5)	0.056 (5)	−0.005 (4)	−0.001 (3)	0.021 (4)
C7	0.045 (4)	0.063 (5)	0.043 (4)	−0.006 (4)	0.002 (3)	0.009 (4)
C8	0.060 (6)	0.089 (7)	0.058 (6)	−0.018 (5)	0.002 (5)	0.028 (5)
C9	0.076 (7)	0.122 (11)	0.046 (5)	−0.016 (7)	0.018 (5)	−0.005 (6)
C10	0.091 (8)	0.098 (9)	0.056 (6)	−0.006 (7)	0.021 (6)	−0.010 (6)
C11	0.081 (7)	0.073 (7)	0.068 (6)	0.007 (6)	0.029 (6)	−0.004 (5)
N1	0.052 (4)	0.050 (4)	0.052 (4)	0.004 (3)	0.015 (3)	0.008 (3)
N2	0.059 (4)	0.059 (4)	0.042 (3)	−0.001 (4)	0.012 (3)	0.008 (3)
Br1	0.0576 (6)	0.0870 (8)	0.0815 (7)	0.0001 (5)	0.0052 (5)	0.0382 (6)
Br2	0.0673 (7)	0.0768 (7)	0.0878 (8)	−0.0131 (5)	0.0173 (6)	0.0197 (6)
Zn1	0.0560 (6)	0.0509 (6)	0.0528 (6)	0.0038 (5)	0.0149 (4)	0.0129 (4)

Geometric parameters (Å, º) top

C1—C2	1.486 (16)	C7—N2	1.346 (11)
C1—H1A	0.9600	C7—C8	1.383 (12)
C1—H1B	0.9600	C8—C9	1.402 (17)
C1—H1C	0.9600	C8—H8	0.9300
C2—N1	1.312 (12)	C9—C10	1.335 (18)
C2—C3	1.388 (15)	C9—H9	0.9300
C3—C4	1.364 (17)	C10—C11	1.355 (15)
C3—H3	0.9300	C10—H10	0.9300
C4—C5	1.368 (16)	C11—N2	1.342 (13)
C4—H4	0.9300	C11—H11	0.9300
C5—C6	1.370 (13)	N1—Zn1	2.057 (7)
C5—H5	0.9300	N2—Zn1	2.048 (7)
C6—N1	1.378 (10)	Br1—Zn1	2.3617 (16)
C6—C7	1.480 (13)	Br2—Zn1	2.3300 (15)

Cg1···Cg2ⁱ	3.762 (5)	Cg2···Cg3ⁱⁱ	3.835 (6)

C2—C1—H1A	109.5	C7—C8—C9	117.7 (10)
C2—C1—H1B	109.5	C7—C8—H8	121.2
H1A—C1—H1B	109.5	C9—C8—H8	121.2
C2—C1—H1C	109.5	C10—C9—C8	120.1 (10)
H1A—C1—H1C	109.5	C10—C9—H9	120.0
H1B—C1—H1C	109.5	C8—C9—H9	120.0
N1—C2—C3	121.8 (10)	C9—C10—C11	120.0 (11)
N1—C2—C1	115.0 (9)	C9—C10—H10	120.0
C3—C2—C1	123.2 (10)	C11—C10—H10	120.0
C4—C3—C2	118.7 (11)	N2—C11—C10	121.8 (11)
C4—C3—H3	120.7	N2—C11—H11	119.1
C2—C3—H3	120.7	C10—C11—H11	119.1
C3—C4—C5	120.3 (10)	C2—N1—C6	119.5 (8)
C3—C4—H4	119.8	C2—N1—Zn1	127.1 (6)
C5—C4—H4	119.8	C6—N1—Zn1	113.3 (6)
C4—C5—C6	119.1 (10)	C11—N2—C7	119.4 (8)
C4—C5—H5	120.5	C11—N2—Zn1	126.6 (7)
C6—C5—H5	120.5	C7—N2—Zn1	113.8 (6)
C5—C6—N1	120.5 (9)	N2—Zn1—N1	80.9 (3)
C5—C6—C7	124.6 (8)	N2—Zn1—Br2	116.8 (2)
N1—C6—C7	114.9 (8)	N1—Zn1—Br2	117.6 (2)
N2—C7—C8	121.0 (9)	N2—Zn1—Br1	110.1 (2)
N2—C7—C6	116.5 (7)	N1—Zn1—Br1	108.6 (2)
C8—C7—C6	122.4 (9)	Br2—Zn1—Br1	117.30 (6)

N1—C2—C3—C4	1.2 (17)	C5—C6—N1—Zn1	−176.7 (7)
C1—C2—C3—C4	−179.0 (12)	C7—C6—N1—Zn1	3.4 (9)
C2—C3—C4—C5	−2.1 (18)	C10—C11—N2—C7	−1.4 (17)
C3—C4—C5—C6	2.5 (17)	C10—C11—N2—Zn1	−175.1 (9)
C4—C5—C6—N1	−2.0 (15)	C8—C7—N2—C11	−0.5 (14)
C4—C5—C6—C7	177.9 (9)	C6—C7—N2—C11	177.8 (9)
C5—C6—C7—N2	−177.1 (9)	C8—C7—N2—Zn1	174.0 (7)
N1—C6—C7—N2	2.9 (11)	C6—C7—N2—Zn1	−7.7 (10)
C5—C6—C7—C8	1.2 (14)	C11—N2—Zn1—N1	−178.6 (9)
N1—C6—C7—C8	−178.8 (8)	C7—N2—Zn1—N1	7.4 (6)
N2—C7—C8—C9	1.3 (15)	C11—N2—Zn1—Br2	−62.2 (9)
C6—C7—C8—C9	−176.9 (9)	C7—N2—Zn1—Br2	123.7 (6)
C7—C8—C9—C10	−0.1 (17)	C11—N2—Zn1—Br1	74.8 (9)
C8—C9—C10—C11	−2 (2)	C7—N2—Zn1—Br1	−99.2 (6)
C9—C10—C11—N2	3 (2)	C2—N1—Zn1—N2	176.6 (9)
C3—C2—N1—C6	−0.8 (15)	C6—N1—Zn1—N2	−5.8 (6)
C1—C2—N1—C6	179.5 (10)	C2—N1—Zn1—Br2	61.0 (9)
C3—C2—N1—Zn1	176.7 (8)	C6—N1—Zn1—Br2	−121.3 (5)
C1—C2—N1—Zn1	−3.0 (14)	C2—N1—Zn1—Br1	−75.2 (8)
C5—C6—N1—C2	1.2 (13)	C6—N1—Zn1—Br1	102.5 (6)
C7—C6—N1—C2	−178.7 (8)

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1C···Br1ⁱⁱⁱ	0.96	2.86	3.805 (14)	169
C8—H8···Br1ⁱⁱ	0.93	2.93	3.812 (12)	159

Symmetry codes: (ii) −x+2, −y+2, −z; (iii) −x+3/2, y+1/2, −z+1/2.

Experimental details

Crystal data
Chemical formula	[ZnBr₂(C₁₁H₁₀N₂)]
M_r	395.40
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	298
a, b, c (Å)	7.6445 (7), 9.7487 (11), 17.8347 (18)
β (°)	96.972 (8)
V (Å³)	1319.3 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	7.89
Crystal size (mm)	0.46 × 0.30 × 0.15

Data collection
Diffractometer	Bruker SMART CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Sheldrick, 2003)
T_min, T_max	0.076, 0.310
No. of measured, independent and observed [I > 2σ(I)] reflections	15389, 3567, 2498
R_int	0.119
(sin θ/λ)_max (Å⁻¹)	0.690

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.086, 0.207, 1.13
No. of reflections	3567
No. of parameters	145
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	2.14, −1.14

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

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1C···Br1ⁱ	0.96	2.86	3.805 (14)	169
C8—H8···Br1ⁱⁱ	0.93	2.93	3.812 (12)	159

Symmetry codes: (i) −x+3/2, y+1/2, −z+1/2; (ii) −x+2, −y+2, −z.

Acknowledgements

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

References

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