catena-Poly[[bis­[1-(2-hydroxy­ethyl)-1H-tetra­zole-κN ⁴]copper(II)]-di-μ-chlorido]: a powder study

Abstract

The crystal structure of the title polymeric complex, [CuCl₂(C₃H₆N₄O)₂]_n, was obtained by the Rietveld refinement from laboratory X-ray powder diffraction data collected at room temperature. The unique Cu^II ion lies on an inversion center and is in a slightly distorted octa­hedral coordination environment. In the hydroxy­ethyl group, all H atoms, the O atom and its attached C atom are disordered over two positions; the site occupancy factors are ca 0.6 and 0.4. The OH group is involved in an intra­molecular O—H⋯N hydrogen bond.

Related literature

For related literature, see: Ivashkevich et al. (2001 ▶); Ivashkevich, Lyakhov et al. (2005 ▶); Ivashkevich, Voitekhovich & Lyakhov (2005 ▶); Stassen et al. (2002 ▶); Werner et al. (1985 ▶); Allen (2002 ▶); Virovets et al. (1995 ▶, 1996 ▶).

Experimental

Crystal data

• [CuCl₂(C₃H₆N₄O)₂]

• M _r = 362.69

• Monoclinic,

• a = 13.3349 (11) Å

• b = 6.7406 (6) Å

• c = 7.3419 (5) Å

• β = 105.450 (8)°

• V = 636.08 (9) ų

• Z = 2

• Cu Kα radiation

• T = 295 (2) K

• Specimen shape: flat sheet

• 30 × 30 × 1 mm

• Specimen prepared at 100 kPa

• Specimen prepared at 295(2) K

• Particle morphology: plate, green

Data collection

• HZG-4A (Carl Zeiss, Jena) diffractometer

• Specimen mounting: packed powder pellet

• Specimen mounted in reflection mode

• Scan method: step

• 2θ_min = 5.0, 2θ_max = 100.0°

• Increment in 2θ = 0.02°

Refinement

• R _p = 0.042

• R _wp = 0.067

• R _exp = 0.086

• R _B = 0.029

• S = 0.78

• Wavelength of incident radiation: 1.5418 Å

• Excluded region(s): none

• Profile function: pseudo-Voigt

• 785 reflections

• 48 parameters

• 21 restraints

• H-atom parameters constrained

• Preferred orientation correction: Marsh–Dollase function (Marsh, 1932 ▶; Dollase, 1986 ▶)

Data collection: local program; cell refinement: FULLPROF (Rodríguez-Carvajal, 2001 ▶); data reduction: local program; program(s) used to refine structure: FULLPROF and SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ▶) and PLATON (Spek, 2003 ▶); software used to prepare material for publication: FULLPROF and PLATON.

Supplementary Material

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

Table 1. Selected geometric parameters (Å, °).

Cu—Cl	2.234 (7)
Cu—N4	1.979 (10)
Cu—Cli	3.008 (7)
Cu—Cuii	4.9835 (4)

Cl—Cu—N4	89.8 (7)
Cl—Cu—Cli	90.8 (2)
Cl—Cu—Cliii	180
Cl—Cu—N4iii	90.2 (7)
Cl—Cu—Cliv	89.2 (2)
Cli—Cu—N4	92.6 (5)
N4—Cu—N4iii	180
Cliv—Cu—N4	87.4 (5)
Cu—Cl—Cuii	143.5 (2)

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .

Table 2. Hydrogen-bond geometry (Å, °).

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1⋯N2	0.82	2.35	3.08 (3)	149
O2—H2⋯N2	0.82	2.46	3.02 (3)	126
C5—H5⋯Clii	0.93	2.72	3.34 (2)	126

Symmetry code: (ii) .

supplementary crystallographic information

Comment

Complexes of copper(II) chloride with substituted tetrazoles attract attention because of their magnetic bahaviour at low temperatures. Among them, there are layered coordination polymers with square grids of only Cu and Cl atoms, of the composition CuCl₂L₂, where L = 1-ethyltetrazole (Virovets et al., 1995), 1-allyltetrazole (Virovets et al., 1996), 1-(2-azidoethyl)terazole (Ivashkevich et al., 2001), 1-(2-chloroethyl)tetrazole (Stassen et al., 2002), 1-benzyltetrazole (Ivashkevich, Voitekhovich & Lyakhov, 2005), and 1-methyltetrazole (Ivashkevich, Lyakhov, Ivashkevich, Degtyarik & Gaponik, 2005). These compounds crystallize in the space group P2₁/c and are isotypic. Here, we present another example, poly[[bis(1-(2-hydroxyethyl)tetrazole-N⁴)copper(II)]-di-µ-chloro], (I), (Fig. 1). As it is difficult to obtain single crystals for structural analysis, the compound (I) was investigated by X-ray powder diffraction.

The Cu atom lies on inversion center and shows a slightly distorted octahedral coordination environment. Equatorial sites are occupied by two trans positioned N atoms and two Cl atoms; Cl atoms lying in axial positions are essentially more distant from the Cu atom (Table 1). Each Cl atom is a bridge between the neighbouring Cu atoms, forming two different in length Cu—Cl bonds, with Cu—Cl—Cu angle of 143.4 (2)°. These bonds are responsible for the formation of polymeric layers parallel to the yz plane (Fig. 2). Within a layer, the shortest Cu···Cu distance is 4.9835 (4) Å, whereas between two neighbouring layers, the closest Cu centers are separated by cell dimension a. Only van der Waals interactions are between the layers.

The 2-hydroxyethyl substituent at the tetrazole ring atom N1 was found to be disordered over two positions, with almost equal occupancies of 0.562 (12) for C71—O1 and 0.438 (12) for C72—O2 (Fig. 1). For both positions, OH groups are involved in intramolecular hydrogen bonds O—H···N. There are also hydrogen bonds C—H···Cl (Table 2).

Experimental

A solution, containing 2.13 g (0.0125 mol) of CuCl₂.2H₂O in 75 ml of ethanol, was added to a slightly heated solution of 1-(2-hydroxyethyl)tetrazole (2.85 g, 0.025 mol) in a solvent mixture (45 ml of ethanol and 30 ml of n-buthanol), with stirring at room temperature. After stirring the reaction mixture for 10 min, the obtained green crystals of (I) were filtered off, air dried and recrystallized from (ethanol—n-buthanol) mixture (v/v = 4:1) [3.55 g, yield 78.3%]. Calc.(%): Cu 17.52, Cl 19.59. Found (%): Cu 18.2, Cl 20.1.

Refinement

The monoclinic unit-cell dimensions of (I) were determined with the indexing program TREOR90 (Werner et al., 1985). The obtained values indicated isotypism of (I) with layered coordination polymers CuCl₂L₂ (L = 1-alkyltetrazole) that crystallize in the monoclinic space group P2₁/c. This space group and the atomic coordinates of CuCl₂L₂ with L = 1-ethyltetrazole (Virovets et al., 1995) were used as starting parameters for the Rietveld refinement with the FULLPROF program (Rodríguez-Carvajal, 2001). Background intensity was found by Fourier filtering technique as implemented in the FULLPROF program, under visual inspection of the resulting background curve. Correction for profile asymmetry was made for reflections up to 2θ=30°. A Marsh-Dollase correction of intensities for [100] preferred orientation of plate-like grains in the sample (Marsh, 1932; Dollase, 1986) was applied.

The Rietveld refinement, performed primarily by using individual isotropic displacement parameters for non-H atoms, revealed rather high values of B_iso for atoms of C—O fragment. From this fact an assumption was made that C—O fragment was disordered over two positions. It was confirmed in subsequent refinement by introducing disorder positions for the above C and O atoms. In final refinement, all non-H atoms were refined with overall B_iso parameter.

All H atoms were placed in geometrically calculated positions, using the program SHELXL97 (Sheldrick, 2008), with displacement parameter B_iso(H)=1.2B_iso(C) for H atom at C5 tetrazole ring atom and B_iso(H)=1.5B_iso(C,O) for the methylene and hydroxyl groups.

Soft restraints on some interatomic distances and bond angles of ligand molecule, based on a geometric analysis of a large number of 1-substituted tetrazoles (Cambridge Structural Database, version 5.29 of November 2007; Allen, 2002), were used in the Rietved refinement. Observed, calculated and difference difraction patterns are shown in Fig. 3.

Figures

Fig. 1.

The asymmetric unit of (I) with the atomic numbering scheme. 2-hydroxyethyl substituent is shown as disordered over two positions.

Fig. 2.

Layered structure of (I), viewed along the b axis. Disordered 2-hydroxyethyl substituent is shown only in position with occupancy factor of 0.562 (12).

Fig. 3.

The Rietveld plot, showing the observed (circles), calculated (line) and difference patterns for (I). The reflection positions are shown above the difference pattern.

Crystal data

[CuCl2(C3H6N4O)2]	F000 = 366.0
Mr = 362.69	Dx = 1.894 Mg m−3
Monoclinic, P21/c	Cu Kα radiation λ = 1.5418 Å
Hall symbol: -P 2ybc	T = 295 (2) K
a = 13.3349 (11) Å	Specimen shape: flat sheet
b = 6.7406 (6) Å	30 × 30 × 1 mm
c = 7.3419 (5) Å	Specimen prepared at 100 kPa
β = 105.450 (8)º	Specimen prepared at 295(2) K
V = 636.08 (9) Å3	Particle morphology: plate, green
Z = 2

Data collection

HZG-4A (Carl Zeiss, Jena) diffractometer	T = 295 K
Monochromator: Ni filtered	2θmin = 5.00, 2θmax = 100.00º
Specimen mounting: packed powder pellet	Increment in 2θ = 0.02º
Specimen mounted in reflection mode	Increment in 2θ = 0.02º
Scan method: step

Refinement

Refinement on Inet	Excluded region(s): none
Least-squares matrix: full with fixed elements per cycle	Profile function: psevdo-Voigt
Rp = 0.042	48 parameters
Rwp = 0.067	21 restraints
Rexp = 0.086	H-atom parameters constrained
RB = 0.029	Weighting scheme based on measured s.u.'s ?
S = 0.78	(Δ/σ)max = 0.02
Wavelength of incident radiation: 1.5418 Å	Preferred orientation correction: Marsh–Dollase function (Marsh, 1932; Dollase, 1986)

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
Cu	0.00000	0.00000	0.50000	0.0309 (10)*
Cl	−0.0624 (4)	0.2048 (11)	0.2569 (10)	0.0309 (10)*
N1	0.24708 (16)	0.3706 (2)	0.583 (4)	0.0309 (10)*
N2	0.2982 (2)	0.19676 (13)	0.595 (3)	0.0309 (10)*
N3	0.2308 (2)	0.05581 (18)	0.577 (3)	0.0309 (10)*
N4	0.1358 (4)	0.1377 (3)	0.553 (4)	0.0309 (10)*
C5	0.14654 (16)	0.3314 (4)	0.545 (5)	0.0309 (10)*
H5	0.09292	0.42403	0.51621	0.0309 (10)*
C6	0.3006 (6)	0.5643 (10)	0.5973 (16)	0.0309 (10)*
H61A	0.24602	0.66346	0.56434	0.0309 (10)*	0.562 (12)
H61B	0.33551	0.56618	0.49731	0.0309 (10)*	0.562 (12)
C71	0.3778 (18)	0.641 (2)	0.768 (3)	0.0309 (10)*	0.562 (12)
H71A	0.41791	0.74586	0.73283	0.0309 (10)*	0.562 (12)
H71B	0.34071	0.69633	0.85467	0.0309 (10)*	0.562 (12)
O1	0.4451 (15)	0.489 (3)	0.862 (5)	0.0309 (10)*	0.562 (12)
H1	0.42627	0.38207	0.81168	0.0309 (10)*	0.562 (12)
H62A	0.31564	0.60902	0.72756	0.0309 (10)*	0.438 (12)
H62B	0.25331	0.65967	0.52039	0.0309 (10)*	0.438 (12)
C72	0.3987 (12)	0.565 (7)	0.539 (4)	0.0309 (10)*	0.438 (12)
H72A	0.38957	0.48960	0.42321	0.0309 (10)*	0.438 (12)
H72B	0.41727	0.69967	0.51599	0.0309 (10)*	0.438 (12)
O2	0.479 (2)	0.480 (6)	0.684 (5)	0.0309 (10)*	0.438 (12)
H2	0.46854	0.35907	0.68929	0.0309 (10)*	0.438 (12)

Geometric parameters (Å, °)

Cu—Cl	2.234 (7)	N3—N4	1.350 (11)
Cu—N4	1.979 (10)	N4—C5	1.316 (4)
Cu—Cli	3.008 (7)	C6—C71	1.49 (2)
Cu—Clii	2.234 (7)	C6—C72	1.48 (2)
Cu—N4ii	1.979 (10)	C5—H5	0.9300
Cu—Cliii	3.008 (7)	C6—H61B	0.9700
O1—C71	1.41 (3)	C6—H62A	0.9700
O2—C72	1.42 (5)	C6—H61A	0.9700
O1—H1	0.8200	C6—H62B	0.9700
O2—H2	0.8200	C71—H71A	0.9700
N1—N2	1.346 (6)	C71—H71B	0.9700
N1—C5	1.321 (15)	C72—H72A	0.9700
N1—C6	1.478 (8)	C72—H72B	0.9700
N2—N3	1.291 (7)	Cu—Cuiv	4.9835 (4)
Cl—Cu—N4	89.8 (7)	N1—C6—C72	115 (2)
Cl—Cu—Cli	90.8 (2)	N1—C6—C71	125.5 (14)
Cl—Cu—Clii	180	O1—C71—C6	111.5 (15)
Cl—Cu—N4ii	90.2 (7)	O2—C72—C6	110 (2)
Cl—Cu—Cliii	89.2 (2)	N1—C5—H5	126.00
Cli—Cu—N4	92.6 (5)	N4—C5—H5	126.00
Clii—Cu—N4	90.2 (7)	N1—C6—H61B	106.00
N4—Cu—N4ii	180	N1—C6—H62A	108.00
Cliii—Cu—N4	87.4 (5)	N1—C6—H62B	108.00
Cli—Cu—Clii	89.2 (2)	C71—C6—H61A	106.00
Cli—Cu—N4ii	87.4 (5)	C71—C6—H61B	106.00
Cli—Cu—Cliii	180.00	H61A—C6—H61B	106.00
Clii—Cu—N4ii	89.8 (7)	C72—C6—H62A	109.00
Clii—Cu—Cliii	90.8 (2)	C72—C6—H62B	109.00
Cliii—Cu—N4ii	92.6 (5)	H62A—C6—H62B	107.00
Cu—Cl—Cuiv	143.5 (2)	N1—C6—H61A	106.00
C71—O1—H1	109.00	O1—C71—H71A	109.00
C72—O2—H2	109.00	O1—C71—H71B	109.00
N2—N1—C6	122.6 (7)	C6—C71—H71B	109.00
C5—N1—C6	129.4 (6)	H71A—C71—H71B	108.00
N2—N1—C5	107.9 (5)	C6—C71—H71A	109.00
N1—N2—N3	107.9 (6)	C6—C72—H72A	110.00
N2—N3—N4	108.4 (3)	C6—C72—H72B	110.00
Cu—N4—N3	127.6 (3)	O2—C72—H72A	110.00
N3—N4—C5	107.5 (8)	O2—C72—H72B	109.00
Cu—N4—C5	124.1 (9)	H72A—C72—H72B	108.00
N1—C5—N4	107.8 (9)

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

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1···N2	0.8200	2.3500	3.08 (3)	149.00
O2—H2···N2	0.8200	2.4600	3.02 (3)	126.00
C5—H5···Cliv	0.9300	2.7200	3.34 (2)	126.00

Symmetry codes: (iv) −x, y+1/2, −z+1/2.