Dibromido(2,2′:6′,2′′-terpyridine-κ³ N,N′,N′′)zinc(II)

Abstract

In the title compound, [ZnBr₂(C₁₅H₁₁N₃)], the Zn^II ion is five-coordinated by the three N atoms from a 2,2′:6′,2′′-terpyridine ligand (terpy) and two bromide anions in a distorted trigonal bipyramidal configuration. Each mol­ecule is situated on a twofold rotational axis that passes through the Zn^II ion and the central ring of the terpy ligand. In the crystal structure, aromatic π–π inter­actions between terpy ligands [centroid–centroid distances = 3.6265 (9) Å] link mol­ecules into stacks propagated in the [001] direction.

Related literature

For related structures, see: Alizadeh et al. (2009 ▶); Mahmoudi et al. (2009 ▶); Huang et al. (2009 ▶); Ma et al. (2009 ▶); Bai et al. (2009 ▶).

Experimental

Crystal data

• [ZnBr₂(C₁₅H₁₁N₃)]

• M _r = 458.46

• Monoclinic,

• a = 17.0972 (5) Å

• b = 9.3528 (3) Å

• c = 11.5334 (4) Å

• β = 126.051 (1)°

• V = 1491.08 (8) ų

• Z = 4

• Mo Kα radiation

• μ = 7.00 mm⁻¹

• T = 296 K

• 0.20 × 0.18 × 0.16 mm

Data collection

• Bruker SMART APEXII CCD diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 2005 ▶) T _min = 0.335, T _max = 0.401 (expected range = 0.273–0.326)

• 9665 measured reflections

• 1457 independent reflections

• 1371 reflections with I > 2σ(I)

• R _int = 0.019

Refinement

• R[F ² > 2σ(F ²)] = 0.015

• wR(F ²) = 0.039

• S = 1.08

• 1457 reflections

• 97 parameters

• H-atom parameters constrained

• Δρ_max = 0.27 e Å⁻³

• Δρ_min = −0.29 e Å⁻³

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXTL.

Supplementary Material

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

supplementary crystallographic information

Comment

As a contribution to structural characterization of 2,2':6',2''-terpyridine complexes (Alizadeh et al., 2009; Huang et al., 2009; Ma et al., 2009; Bai et al., 2009) we present here the title complex (I).

In (I) (Fig. 1), the Zn^II ion is five-coordinated in a distorted trigonal bipyramidal configuration by three N atoms from a 2,2':6',2''-terpyridine ligand and by two Br anions. The Zn–Br and Zn–N bond lengths are within normal ranges (Mahmoudi et al., 2009).

In the crystal structure, the π–π stacking interactions between aromatic rings of Cg1 and Cg2 [Cg1 and Cg2 are (N1, C6 — C8, C7ⁱ, C6ⁱ) and (N2, C1 — C5) ring centroids, respectively, symmetry code: (i) -x + 1, y, -z + 1/2] are observed, with a centroid–centroid distances of 3.6265 (9) Å.

Experimental

The title compound was synthesized hydrothermally in a Teflon-lined autoclave (25 mL) by heating a mixture of 2,2':6',2''-terpyridine (0.2 mmol), ZnBr₂ (0.2 mmol) and one drop of Et₃N (pH ≈ 8–9) in water (10 mL) at 393 K for 3 d. Crystals suitable for X-ray analysis were obtained.

Refinement

All H atoms were included in calculated positions, with C—H distances fixed to 0.93 Å and were refined in the riding-model approximation, with U_iso(H) = 1.2 U_eq (C).

Figures

Fig. 1.

The molecular structure of the title compound with the atom-labelling scheme [symmetry code: (A) -x, + 1, y, -z + 1/2]. Displacement ellipsoids are drawn at the 50% probability level. H atoms are presented as small spheres of arbitrary radius.

Fig. 2.

A portion of the crystal packing showing the π–π interactions (dashed lines) between the aromatic rings.

Crystal data

[ZnBr2(C15H11N3)]	F(000) = 888
Mr = 458.46	Dx = 2.042 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1580 reflections
a = 17.0972 (5) Å	θ = 2.5–26.3°
b = 9.3528 (3) Å	µ = 7.00 mm−1
c = 11.5334 (4) Å	T = 296 K
β = 126.051 (1)°	Block, colourless
V = 1491.08 (8) Å3	0.20 × 0.18 × 0.16 mm
Z = 4

Data collection

Bruker SMART APEXII CCD diffractometer	1457 independent reflections
Radiation source: fine-focus sealed tube	1371 reflections with I > 2σ(I)
graphite	Rint = 0.019
φ and ω scans	θmax = 26.0°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2005)	h = −21→21
Tmin = 0.335, Tmax = 0.401	k = −11→11
9665 measured reflections	l = −14→14

Refinement

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)] = 0.015	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.039	H-atom parameters constrained
S = 1.08	w = 1/[σ2(Fo2) + (0.0184P)2 + 1.2604P] where P = (Fo2 + 2Fc2)/3
1457 reflections	(Δ/σ)max < 0.001
97 parameters	Δρmax = 0.27 e Å−3
0 restraints	Δρmin = −0.29 e Å−3

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.

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 (Ų)

	x	y	z	Uiso*/Ueq
Br1	0.380531 (15)	0.11870 (2)	0.03979 (2)	0.04022 (8)
Zn1	0.5000	0.25499 (3)	0.2500	0.02736 (8)
N1	0.5000	0.4802 (2)	0.2500	0.0253 (4)
N2	0.58982 (11)	0.31649 (16)	0.18054 (15)	0.0288 (3)
C1	0.63375 (14)	0.2248 (2)	0.1474 (2)	0.0352 (4)
H1	0.6256	0.1272	0.1525	0.042*
C2	0.69093 (14)	0.2696 (2)	0.1056 (2)	0.0392 (4)
H2	0.7210	0.2033	0.0838	0.047*
C3	0.70254 (14)	0.4137 (2)	0.0970 (2)	0.0394 (4)
H3	0.7411	0.4461	0.0700	0.047*
C4	0.65606 (13)	0.5102 (2)	0.12890 (18)	0.0346 (4)
H4	0.6620	0.6081	0.1219	0.042*
C5	0.60056 (12)	0.45792 (18)	0.17152 (16)	0.0268 (4)
C6	0.54892 (12)	0.55136 (18)	0.21013 (16)	0.0263 (3)
C7	0.54910 (13)	0.69976 (19)	0.20701 (19)	0.0337 (4)
H7	0.5815	0.7485	0.1767	0.040*
C8	0.5000	0.7736 (3)	0.2500	0.0367 (6)
H8	0.5000	0.8730	0.2500	0.044*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Br1	0.04910 (14)	0.03300 (12)	0.03959 (12)	−0.01116 (8)	0.02667 (10)	−0.00711 (7)
Zn1	0.03545 (17)	0.01984 (14)	0.03395 (16)	0.000	0.02441 (14)	0.000
N1	0.0293 (10)	0.0231 (10)	0.0253 (9)	0.000	0.0170 (9)	0.000
N2	0.0322 (8)	0.0264 (8)	0.0335 (7)	−0.0007 (6)	0.0224 (7)	0.0004 (6)
C1	0.0407 (11)	0.0311 (10)	0.0417 (10)	0.0025 (8)	0.0285 (9)	−0.0011 (8)
C2	0.0372 (11)	0.0487 (12)	0.0398 (10)	0.0025 (9)	0.0271 (9)	−0.0038 (9)
C3	0.0354 (10)	0.0545 (12)	0.0380 (10)	−0.0069 (9)	0.0271 (9)	−0.0022 (9)
C4	0.0367 (10)	0.0359 (10)	0.0339 (9)	−0.0072 (8)	0.0222 (8)	0.0005 (8)
C5	0.0268 (9)	0.0287 (9)	0.0235 (7)	−0.0027 (7)	0.0139 (7)	0.0004 (7)
C6	0.0274 (9)	0.0247 (8)	0.0237 (7)	−0.0027 (7)	0.0133 (7)	0.0007 (6)
C7	0.0360 (10)	0.0268 (9)	0.0351 (9)	−0.0042 (8)	0.0193 (8)	0.0030 (7)
C8	0.0426 (16)	0.0201 (12)	0.0409 (14)	0.000	0.0210 (13)	0.000

Geometric parameters (Å, °)

Br1—Zn1	2.4179 (2)	C2—H2	0.9300
Zn1—N1	2.106 (2)	C3—C4	1.388 (3)
Zn1—N2i	2.1861 (14)	C3—H3	0.9300
Zn1—N2	2.1861 (14)	C4—C5	1.389 (2)
Zn1—Br1i	2.4179 (2)	C4—H4	0.9300
N1—C6i	1.3441 (19)	C5—C6	1.485 (2)
N1—C6	1.3441 (19)	C6—C7	1.388 (3)
N2—C1	1.336 (2)	C7—C8	1.385 (2)
N2—C5	1.348 (2)	C7—H7	0.9300
C1—C2	1.385 (3)	C8—C7i	1.385 (2)
C1—H1	0.9300	C8—H8	0.9300
C2—C3	1.374 (3)
N1—Zn1—N2i	74.75 (4)	C3—C2—H2	120.5
N1—Zn1—N2	74.75 (4)	C1—C2—H2	120.5
N2i—Zn1—N2	149.49 (8)	C2—C3—C4	119.27 (17)
N1—Zn1—Br1	121.815 (7)	C2—C3—H3	120.4
N2i—Zn1—Br1	98.34 (4)	C4—C3—H3	120.4
N2—Zn1—Br1	97.60 (4)	C3—C4—C5	118.78 (18)
N1—Zn1—Br1i	121.815 (7)	C3—C4—H4	120.6
N2i—Zn1—Br1i	97.60 (4)	C5—C4—H4	120.6
N2—Zn1—Br1i	98.34 (4)	N2—C5—C4	121.69 (16)
Br1—Zn1—Br1i	116.370 (14)	N2—C5—C6	114.99 (14)
C6i—N1—C6	120.6 (2)	C4—C5—C6	123.32 (16)
C6i—N1—Zn1	119.68 (10)	N1—C6—C7	121.01 (16)
C6—N1—Zn1	119.68 (10)	N1—C6—C5	114.25 (15)
C1—N2—C5	118.88 (15)	C7—C6—C5	124.74 (15)
C1—N2—Zn1	124.80 (12)	C8—C7—C6	118.57 (17)
C5—N2—Zn1	116.32 (11)	C8—C7—H7	120.7
N2—C1—C2	122.43 (18)	C6—C7—H7	120.7
N2—C1—H1	118.8	C7i—C8—C7	120.2 (2)
C2—C1—H1	118.8	C7i—C8—H8	119.9
C3—C2—C1	118.93 (18)	C7—C8—H8	119.9
N2i—Zn1—N1—C6i	0.68 (9)	C1—C2—C3—C4	−0.6 (3)
N2—Zn1—N1—C6i	−179.32 (9)	C2—C3—C4—C5	1.3 (3)
Br1—Zn1—N1—C6i	91.12 (8)	C1—N2—C5—C4	−0.1 (2)
Br1i—Zn1—N1—C6i	−88.88 (8)	Zn1—N2—C5—C4	179.88 (12)
N2i—Zn1—N1—C6	−179.32 (9)	C1—N2—C5—C6	179.87 (15)
N2—Zn1—N1—C6	0.68 (9)	Zn1—N2—C5—C6	−0.19 (18)
Br1—Zn1—N1—C6	−88.88 (8)	C3—C4—C5—N2	−0.9 (3)
Br1i—Zn1—N1—C6	91.12 (8)	C3—C4—C5—C6	179.12 (16)
N1—Zn1—N2—C1	179.71 (15)	C6i—N1—C6—C7	−0.96 (12)
N2i—Zn1—N2—C1	179.71 (15)	Zn1—N1—C6—C7	179.04 (12)
Br1—Zn1—N2—C1	−59.30 (14)	C6i—N1—C6—C5	179.02 (15)
Br1i—Zn1—N2—C1	58.90 (14)	Zn1—N1—C6—C5	−0.98 (15)
N1—Zn1—N2—C5	−0.23 (11)	N2—C5—C6—N1	0.74 (19)
N2i—Zn1—N2—C5	−0.23 (11)	C4—C5—C6—N1	−179.33 (14)
Br1—Zn1—N2—C5	120.76 (11)	N2—C5—C6—C7	−179.29 (16)
Br1i—Zn1—N2—C5	−121.05 (11)	C4—C5—C6—C7	0.6 (3)
C5—N2—C1—C2	0.8 (3)	N1—C6—C7—C8	1.9 (2)
Zn1—N2—C1—C2	−179.16 (14)	C5—C6—C7—C8	−178.10 (13)
N2—C1—C2—C3	−0.4 (3)	C6—C7—C8—C7i	−0.91 (11)

Symmetry codes: (i) −x+1, y, −z+1/2.