catena-Poly[[(5,5′-dimethyl-2,2′-bi­pyridine-κ² N,N′)cadmium(II)]-di-μ-iodido]

Abstract

In the title coordination polymer, [CdI₂(C₁₂H₁₂N₂)]_n, the Cd²⁺ ion lies on a twofold rotation axis: it is six-coordinated in a distorted cis-CdN₂I₄ octa­hedral geometry by two N atoms from a chelating 5,5′-dimethyl-2,2′-bipyridine ligands and four bridging iodide anions. The bridging function of the iodide ions leads to a chain structure propagating in [001].

Related literature

For related structures, see: Ahmadi et al. (2008 ▶); Albada et al. (2004 ▶); Amani et al. (2007 ▶, 2009 ▶); Chattopadhyay et al. (2008 ▶); Guo et al. (2006 ▶); Kalateh et al. (2008 ▶, 2010 ▶); Khalighi et al. (2008 ▶); Maheshwari et al. (2007 ▶); Tadayon Pour et al. (2008 ▶); Yu et al. (2007 ▶).

Experimental

Crystal data

• [CdI₂(C₁₂H₁₂N₂)]

• M _r = 550.45

• Monoclinic,

• a = 19.086 (4) Å

• b = 10.057 (2) Å

• c = 7.8451 (16) Å

• β = 101.80 (3)°

• V = 1474.0 (5) ų

• Z = 4

• Mo Kα radiation

• μ = 5.65 mm⁻¹

• T = 298 K

• 0.25 × 0.15 × 0.12 mm

Data collection

• Bruker SMART CCD diffractometer

• Absorption correction: multi-scan (SADABS; Bruker, 1998 ▶) T _min = 0.380, T _max = 0.510

• 8294 measured reflections

• 1981 independent reflections

• 1832 reflections with I > 2σ(I)

• R _int = 0.062

Refinement

• R[F ² > 2σ(F ²)] = 0.037

• wR(F ²) = 0.098

• S = 1.23

• 1981 reflections

• 79 parameters

• H-atom parameters constrained

• Δρ_max = 1.30 e Å⁻³

• Δρ_min = −1.43 e Å⁻³

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

Supplementary Material

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

Table 1. Selected bond lengths (Å).

Cd1—N1	2.347 (3)
Cd1—I1	2.8586 (7)
Cd1—I1i	3.1628 (8)

Symmetry code: (i) .

supplementary crystallographic information

Comment

In a recent paper, we reported the synthes and crystal structure of [Cd(5,5'-dmbpy)(µ-Cl)₂]_n, (Ahmadi et al., 2008) and [Cd(4,4'-dmbpy)(DMSO)I₂], (Kalateh et al., 2010) [where 5,5'-dmbpy is 5,5'-dimethyl-2,2'-bipyridine and 4,4'-dmbpy is 4,4'-dimethyl-2,2'-bipyridine].

5,5'-Dimethyl-2,2'-bipyridine (5,5'-dmbipy), is a good bidentate ligand, and numerous complexes with 5,5'-dmbipy have been prepared, such as that of zinc (Khalighi et al., 2008), indium (Kalateh et al., 2008), iron (Amani et al., 2007), platin (Amani et al., 2009; Maheshwari et al., 2007), copper (Albada et al., 2004) and mercury (Tadayon Pour et al., 2008).

There are several Cd^II polymer complexes, with formula, [Cd(N—N)(µ-I)₂]_n, such as [Cd(phen)(µ-I)₂]_n, (Guo et al., 2006), [Cd(bipy)(µ-I)₂]_n, (Yu et al., 2007) and [Cd(ampy)(µ-I)₂]_n, (Chattopadhyay et al., 2008) [where phen is 1,10-phenanthroline , bipy is 2,2'-bipyridine and ampy is 2-aminomethylpyridine] have been synthesized and characterized by single-crystal X-ray diffraction methods. Here, we report the synthesis and structure of the title compound.

The asymmetric unit of the title compound, (Fig. 1), contains one half -molecule; a twofold rotation axis passes through the Cd atom. The Cd^II atom is six-coordinated in a distorted octahedral configuration by two N atoms from 5,5'-dimethyl-2,2'-bipyridine and four bridging I atoms. The bridging function of the iodo atoms leads to a one-dimensional chain structure. The Cd—I and Cd—N bond lengths and angles (Table 1) are within normal range [Cd(phen)(µ-I)₂]_n, (Guo et al., 2006) and [Cd(bipy)(µ-I)₂]_n, (Yu et al., 2007).

Experimental

A solution of 5,5'-dimethyl-2,2'-bipyridine (0.25 g, 1.33 mmol) in methanol (10 ml) was added to a solution of CdI₂ (0.49 g, 1.33 mmol) in methanol (10 ml) at room temperature. Colourless blocks of (I) were obtained by methanol diffusion to a colorless solution in DMSO. Suitable crystals were isolated after one week (yield; 0.52 g, 71.0%).

Refinement

All H atoms were positioned geometrically, with C—H = 0.93Å and constrained to ride on their parent atoms, with U_iso(H) = 1.2U_eq.

Figures

Fig. 1.

Fragment of a polymeric chain in (I) with displacement ellipsoids drawn at the 50% probability level. [Symmetry code: (a) -x+1, y, -z+5/2].

Crystal data

[CdI2(C12H12N2)]	F(000) = 1008
Mr = 550.45	Dx = 2.480 Mg m−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 351 reflections
a = 19.086 (4) Å	θ = 2.2–29.3°
b = 10.057 (2) Å	µ = 5.65 mm−1
c = 7.8451 (16) Å	T = 298 K
β = 101.80 (3)°	Block, colorless
V = 1474.0 (5) Å3	0.25 × 0.15 × 0.12 mm
Z = 4

Data collection

Bruker SMART CCD diffractometer	1981 independent reflections
Radiation source: fine-focus sealed tube	1832 reflections with I > 2σ(I)
graphite	Rint = 0.062
phi and ω scans	θmax = 29.3°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 1998)	h = −26→26
Tmin = 0.380, Tmax = 0.510	k = −13→12
8294 measured reflections	l = −10→10

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)] = 0.037	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.098	H-atom parameters constrained
S = 1.23	w = 1/[σ2(Fo2) + (0.0571P)2 + 0.4175P] where P = (Fo2 + 2Fc2)/3
1981 reflections	(Δ/σ)max = 0.037
79 parameters	Δρmax = 1.30 e Å−3
0 restraints	Δρmin = −1.43 e Å−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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
C1	0.3791 (2)	0.7656 (5)	1.0047 (5)	0.0482 (9)
H1	0.3615	0.6825	0.9652	0.058*
C2	0.3413 (3)	0.8765 (5)	0.9329 (6)	0.0546 (11)
C3	0.2732 (3)	0.8623 (8)	0.7991 (8)	0.0758 (17)
H3A	0.2792	0.9020	0.6917	0.114*
H3B	0.2350	0.9062	0.8395	0.114*
H3C	0.2619	0.7698	0.7807	0.114*
C4	0.3706 (3)	0.9988 (5)	0.9920 (6)	0.0590 (12)
H4	0.3478	1.0767	0.9473	0.071*
C5	0.4327 (3)	1.0059 (5)	1.1151 (6)	0.0545 (10)
H5	0.4521	1.0881	1.1531	0.065*
C6	0.4666 (2)	0.8885 (4)	1.1833 (5)	0.0398 (8)
N1	0.43894 (18)	0.7698 (3)	1.1264 (4)	0.0414 (7)
Cd1	0.5000	0.57933 (4)	1.2500	0.04719 (14)
I1	0.407345 (14)	0.39302 (3)	1.03947 (3)	0.04393 (12)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C1	0.049 (2)	0.048 (2)	0.0463 (19)	0.0039 (18)	0.0055 (16)	0.0064 (16)
C2	0.050 (2)	0.066 (3)	0.051 (2)	0.013 (2)	0.0171 (18)	0.019 (2)
C3	0.054 (3)	0.100 (5)	0.071 (3)	0.012 (3)	0.005 (2)	0.027 (3)
C4	0.074 (3)	0.049 (3)	0.058 (2)	0.021 (2)	0.023 (2)	0.015 (2)
C5	0.077 (3)	0.035 (2)	0.055 (2)	0.012 (2)	0.023 (2)	0.0084 (17)
C6	0.051 (2)	0.0328 (18)	0.0388 (17)	0.0020 (14)	0.0168 (15)	0.0021 (12)
N1	0.0470 (17)	0.0366 (17)	0.0400 (14)	0.0018 (13)	0.0074 (12)	0.0052 (12)
Cd1	0.0564 (3)	0.0300 (2)	0.0463 (2)	0.000	−0.01021 (18)	0.000
I1	0.04992 (19)	0.03831 (18)	0.04068 (17)	−0.00834 (9)	0.00254 (11)	−0.00433 (8)

Geometric parameters (Å, °)

C1—N1	1.331 (6)	C5—H5	0.9300
C1—C2	1.384 (6)	C6—N1	1.344 (5)
C1—H1	0.9300	C6—C6i	1.474 (9)
C2—C4	1.391 (8)	Cd1—N1	2.347 (3)
C2—C3	1.501 (8)	Cd1—N1i	2.347 (3)
C3—H3A	0.9600	Cd1—I1	2.8586 (7)
C3—H3B	0.9600	Cd1—I1i	2.8586 (7)
C3—H3C	0.9600	Cd1—I1ii	3.1628 (8)
C4—C5	1.369 (9)	Cd1—I1iii	3.1629 (8)
C4—H4	0.9300	I1—Cd1iii	3.1629 (8)
C5—C6	1.399 (6)
N1—C1—C2	124.4 (5)	C5—C6—C6i	122.5 (3)
N1—C1—H1	117.8	C1—N1—C6	119.2 (4)
C2—C1—H1	117.8	C1—N1—Cd1	123.4 (3)
C1—C2—C4	115.8 (5)	C6—N1—Cd1	117.3 (3)
C1—C2—C3	120.8 (5)	N1i—Cd1—N1	70.55 (18)
C4—C2—C3	123.3 (5)	N1i—Cd1—I1	165.97 (9)
C2—C3—H3A	109.5	N1—Cd1—I1	95.74 (9)
C2—C3—H3B	109.5	N1i—Cd1—I1i	95.74 (9)
H3A—C3—H3B	109.5	N1—Cd1—I1i	165.97 (9)
C2—C3—H3C	109.5	I1—Cd1—I1i	98.09 (3)
H3A—C3—H3C	109.5	N1i—Cd1—I1ii	86.26 (8)
H3B—C3—H3C	109.5	N1—Cd1—I1ii	85.51 (8)
C5—C4—C2	120.9 (4)	I1—Cd1—I1ii	95.844 (16)
C5—C4—H4	119.6	I1i—Cd1—I1ii	90.771 (16)
C2—C4—H4	119.6	N1i—Cd1—I1iii	85.51 (8)
C4—C5—C6	119.4 (5)	N1—Cd1—I1iii	86.26 (8)
C4—C5—H5	120.3	I1—Cd1—I1iii	90.771 (16)
C6—C5—H5	120.3	I1i—Cd1—I1iii	95.842 (16)
N1—C6—C5	120.2 (4)	I1ii—Cd1—I1iii	169.91 (2)
N1—C6—C6i	117.4 (2)	Cd1—I1—Cd1iii	89.229 (16)
N1—C1—C2—C4	1.8 (7)	C6—N1—Cd1—N1i	−0.26 (19)
N1—C1—C2—C3	−178.5 (4)	C1—N1—Cd1—I1	2.9 (3)
C1—C2—C4—C5	−0.7 (7)	C6—N1—Cd1—I1	−177.2 (3)
C3—C2—C4—C5	179.6 (5)	C1—N1—Cd1—I1i	−167.5 (2)
C2—C4—C5—C6	−0.5 (7)	C6—N1—Cd1—I1i	12.3 (5)
C4—C5—C6—N1	0.9 (6)	C1—N1—Cd1—I1ii	−92.5 (3)
C4—C5—C6—C6i	−179.7 (4)	C6—N1—Cd1—I1ii	87.4 (3)
C2—C1—N1—C6	−1.5 (6)	C1—N1—Cd1—I1iii	93.3 (3)
C2—C1—N1—Cd1	178.4 (3)	C6—N1—Cd1—I1iii	−86.8 (3)
C5—C6—N1—C1	0.1 (6)	N1i—Cd1—I1—Cd1iii	74.4 (3)
C6i—C6—N1—C1	−179.4 (4)	N1—Cd1—I1—Cd1iii	86.32 (8)
C5—C6—N1—Cd1	−179.8 (3)	I1i—Cd1—I1—Cd1iii	−96.013 (15)
C6i—C6—N1—Cd1	0.7 (5)	I1ii—Cd1—I1—Cd1iii	172.370 (15)
C1—N1—Cd1—N1i	179.8 (4)	I1iii—Cd1—I1—Cd1iii	0.0

Symmetry codes: (i) −x+1, y, −z+5/2; (ii) x, −y+1, z+1/2; (iii) −x+1, −y+1, −z+2.