catena-Poly[[bis­(ethyl­enediamine)copper(II)]-μ-sulfato]

Abstract

In the title compound, [Cu(SO₄)(C₂H₈N₂)₂]_n, the Cu, S and two O atoms lie on a mirror plane. The Cu atom is in a distorted octa­hedral environment and the ethyl­enediamine ligand is in a gauche conformation. The sulfate dianion is bridging, forming a one-dimensional chain. A two-dimensional net parallel to (001) is generated by N—H⋯O hydrogen bonding between the chains.

Related literature

For related Cu(II) ethyl­enediamine complexes, see: Cullen & Lingafelter (1970 ▶); Bertini et al. (1979 ▶); Healy et al. (1978 ▶); Manriquez et al. (1996 ▶); Taylor et al. (2006 ▶). A similar variation of axial Cu—O distances is found in many weakly coord­inating anions such as sulfate (Castro et al., 2002 ▶), nitrate (Plater et al., 2008 ▶), perchlorate (Bernhardt et al., 2001 ▶) or triflate (Liu et al., 2007 ▶). The anisotropic mosaicity was treated according to Duisenberg (1983 ▶).

Experimental

Crystal data

• [Cu(SO₄)(C₂H₈N₂)₂]

• M _r = 279.81

• Orthorhombic,

• a = 14.4959 (3) Å

• b = 9.63748 (8) Å

• c = 13.87746 (17) Å

• V = 1938.73 (5) ų

• Z = 8

• Mo Kα radiation

• μ = 2.47 mm⁻¹

• T = 110 K

• 0.36 × 0.21 × 0.06 mm

Data collection

• Nonius KappaCCD diffractometer

• Absorption correction: analytical (SADABS; Sheldrick, 2008a ▶) T _min = 0.489, T _max = 0.910

• 29167 measured reflections

• 2204 independent reflections

• 1990 reflections with I > 2σ(I)

• R _int = 0.032

Refinement

• R[F ² > 2σ(F ²)] = 0.019

• wR(F ²) = 0.048

• S = 1.10

• 2204 reflections

• 86 parameters

• H atoms treated by a mixture of independent and constrained refinement

• Δρ_max = 0.44 e Å⁻³

• Δρ_min = −0.56 e Å⁻³

Data collection: COLLECT (Nonius, 1999 ▶); cell refinement: PEAKREF (Schreurs, 2005 ▶); data reduction: Eval15 (Schreurs et al., 2010 ▶) and SADABS (Sheldrick, 2008a ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008b ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008b ▶); molecular graphics: PLATON (Spek, 2009 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

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

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

Cu1—N1	2.0173 (8)
Cu1—N2	2.0226 (8)
Cu1—O1	2.3575 (9)
Cu1—O3i	2.4673 (9)

N1ii—Cu1—N1	91.62 (4)
N1—Cu1—N2ii	176.81 (3)
N1—Cu1—N2	85.22 (3)
N2ii—Cu1—N2	97.95 (4)
N1—Cu1—O1	92.50 (3)
N2—Cu1—O1	87.27 (3)
N1—Cu1—O3i	92.95 (3)
N2—Cu1—O3i	87.59 (3)
O1—Cu1—O3i	172.18 (3)

N1—C1—C2—N2

53.74 (10)

Symmetry codes: (i) ; (ii) .

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯O2	0.858 (16)	2.280 (16)	3.0944 (11)	158.5 (14)
N1—H2N⋯O3iii	0.839 (17)	2.274 (17)	3.0642 (11)	157.1 (17)
N2—H3N⋯O2iv	0.845 (17)	2.125 (17)	2.9636 (10)	171.6 (16)
N2—H4N⋯O2v	0.859 (15)	2.210 (15)	3.0308 (10)	159.7 (14)

Symmetry codes: (iii) ; (iv) ; (v) .

supplementary crystallographic information

Comment

Ethylenediamine (en) complexes of transition metals belong to the most studied compounds in inorganic chemistry. In the case of copper sulfate the tris(ethylenediamine) complex is known at room temperature (Cullen & Lingafelter, 1970) as well as at 120 K after a solid-solid phase transition (Bertini et al., 1979). These crystal structures show the copper in an octahedral geometry and the sulfate is not coordinated to the metal but hydrogen bonded to the amine groups.

Here, we report the crystal structure of the bis(ethylenediamine) complex of copper sulfate (I), in which the sulfate is bridging two copper centers. The compound thus forms a polymeric chain by coordination, which runs in the direction of the c axis (Fig. 1). The copper, the sulfur and two O atoms are in special positions on the crystallographic mirror plane of the orthorhombic space group Cmca. Bridging sulfate ions are very common in copper complexes. For example, in [Cu(en)(H₂O)₂]SO₄, the sulfate is a bridging ligand and a one-dimensional chain is formed by coordination (Healy et al., 1978; Manriquez et al., 1996; Taylor et al., 2006).

As expected, the ethylenediamine ligand is in a gauche conformation (Table 1) and the copper is in a distorted octahedral environment. The nitrogen atoms form the equatorial plane with Cu—N distances (2.0173 (8) and 2.0226 (8) Å), which are shorter than in the room temperature structure of the tris(ethylenediamine) complex (2.150 (2) Å). The two axial positions are occupied by oxygen atoms of sulfate anions with much longer distances than in the equatorial plane. This can be explained by the Jahn-Teller effect in Cu(II) compounds. The Cu—O distances (2.3575 (9) and 2.4673 (9) Å) also differ significantly compared to each other. Such differences are not uncommon with copper complexes of weakly coordinating anions like sulfate (Castro et al., 2002), nitrate (Plater et al., 2008), perchlorate (Bernhardt et al., 2001) or trifluoromethanesulfonate (Liu et al., 2007).

The coordinated NH₂ groups act as hydrogen bond donors and the non-coordinated sulfate O-atoms act as acceptors (Table 2). Two hydrogen bonds are formed within the coordination polymer via H1N and H4N. Two hydrogen bonds via H2N and H3N are between the chains resulting in a two-dimensional net in the b,c-plane (Figures 2 and 3). This two-dimensional motif is also reflected in the plate shaped crystal habitus, where the a-direction has the smallest dimension.

Experimental

2.04 g of copper sulfate pentahydrate (8.17 mmol) were dissolved in 150 ml of water and brought to boiling temperature. Then 2 ml of ethylenediamine (37 mmol) were added dropwise. The resulting deep blue solution was concentrated at 333 K and atmospheric pressure. In the concentrated solution, crystals appeared after 2 days of evaporation at room temperature.

Refinement

An anisotropic mosaic model was used in the intensity integration with hkl = (0,0,1) as anisotropic vector (Duisenberg, 1983). Hydrogen atoms were located in difference Fourier maps. N—H hydrogen atoms were refined freely with isotropic displacement parameters. C—H hydrogen atoms were refined using a riding model with C—H = 0.99 Å and with U_iso(H) = 1.2 times U_eq(C).

Figures

Fig. 1.

: Displacement ellipsoid plot of (I), drawn at the 50% probability level. Only three units of the polymeric chain are shown. View along the b axis. Symmetry operations i: -x, 0.5 - y, z - 1/2; ii: -x, 0.5 - y, z + 1/2; iii: -x, y, z.

Fig. 2.

: Packing of (I) in the crystal viewed along the b axis. C—H hydrogen atoms are omitted for clarity. Hydrogen bonds are drawn as dashed lines.

Fig. 3.

: Packing of (I) in the crystal viewed along the a axis. C—H hydrogen atoms are omitted for clarity. Hydrogen bonds are drawn as dashed lines.

Crystal data

[Cu(SO4)(C2H8N2)2]	F(000) = 1160
Mr = 279.81	Dx = 1.917 Mg m−3
Orthorhombic, Cmca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2bc 2	Cell parameters from 21936 reflections
a = 14.4959 (3) Å	θ = 2.5–35.0°
b = 9.63748 (8) Å	µ = 2.47 mm−1
c = 13.87746 (17) Å	T = 110 K
V = 1938.73 (5) Å3	Plate, blue
Z = 8	0.36 × 0.21 × 0.06 mm

Data collection

Nonius KappaCCD diffractometer	2204 independent reflections
Radiation source: rotating anode	1990 reflections with I > 2σ(I)
graphite	Rint = 0.032
φ and ω scans	θmax = 35.0°, θmin = 2.8°
Absorption correction: analytical (SADABS; Sheldrick, 2008a)	h = −23→23
Tmin = 0.489, Tmax = 0.910	k = −15→15
29167 measured reflections	l = −20→22

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)] = 0.019	Hydrogen site location: difference Fourier map
wR(F2) = 0.048	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	w = 1/[σ2(Fo2) + (0.0208P)2 + 2.1845P] where P = (Fo2 + 2Fc2)/3
2204 reflections	(Δ/σ)max = 0.001
86 parameters	Δρmax = 0.44 e Å−3
0 restraints	Δρmin = −0.56 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
Cu1	0.0000	0.226359 (15)	0.385553 (11)	0.00587 (4)
S1	0.0000	0.24252 (3)	0.13888 (2)	0.00541 (5)
O1	0.0000	0.32265 (9)	0.22939 (6)	0.00932 (16)
O2	0.08343 (5)	0.15354 (7)	0.13383 (5)	0.01049 (12)
O3	0.0000	0.34145 (9)	0.05699 (7)	0.00990 (16)
N1	0.09978 (5)	0.08890 (8)	0.35157 (6)	0.00890 (13)
H1N	0.0983 (10)	0.0830 (15)	0.2899 (12)	0.018 (4)*
H2N	0.0882 (13)	0.0121 (18)	0.3774 (10)	0.022 (4)*
N2	0.10526 (6)	0.35659 (8)	0.41674 (6)	0.00842 (12)
H3N	0.0944 (12)	0.4387 (18)	0.3986 (11)	0.020 (4)*
H4N	0.1142 (11)	0.3552 (15)	0.4779 (11)	0.016 (4)*
C1	0.18950 (6)	0.14531 (9)	0.38195 (7)	0.01121 (15)
H1A	0.2397	0.1034	0.3434	0.013*
H1B	0.2007	0.1241	0.4508	0.013*
C2	0.18704 (7)	0.30147 (9)	0.36647 (7)	0.01045 (15)
H2A	0.2438	0.3445	0.3926	0.013*
H2B	0.1833	0.3227	0.2968	0.013*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
Cu1	0.00700 (7)	0.00409 (6)	0.00652 (7)	0.000	0.000	−0.00089 (4)
S1	0.00864 (12)	0.00388 (10)	0.00371 (11)	0.000	0.000	−0.00008 (8)
O1	0.0172 (4)	0.0071 (4)	0.0036 (4)	0.000	0.000	−0.0017 (3)
O2	0.0111 (3)	0.0101 (3)	0.0102 (3)	0.0040 (2)	0.0003 (2)	−0.0006 (2)
O3	0.0192 (4)	0.0057 (3)	0.0048 (4)	0.000	0.000	0.0012 (3)
N1	0.0094 (3)	0.0064 (3)	0.0109 (3)	−0.0003 (2)	−0.0013 (3)	−0.0010 (2)
N2	0.0126 (3)	0.0064 (3)	0.0063 (3)	−0.0012 (2)	0.0005 (2)	−0.0004 (2)
C1	0.0091 (4)	0.0088 (3)	0.0157 (4)	0.0001 (3)	−0.0027 (3)	−0.0002 (3)
C2	0.0103 (4)	0.0094 (3)	0.0116 (4)	−0.0024 (3)	0.0012 (3)	−0.0003 (3)

Geometric parameters (Å, °)

Cu1—N1i	2.0172 (8)	N1—H1N	0.858 (16)
Cu1—N1	2.0173 (8)	N1—H2N	0.839 (17)
Cu1—N2i	2.0226 (8)	N2—C2	1.4745 (12)
Cu1—N2	2.0226 (8)	N2—H3N	0.845 (17)
Cu1—O1	2.3575 (9)	N2—H4N	0.859 (15)
Cu1—O3ii	2.4673 (9)	C1—C2	1.5207 (13)
S1—O1	1.4745 (9)	C1—H1A	0.9900
S1—O3	1.4834 (9)	C1—H1B	0.9900
S1—O2i	1.4842 (7)	C2—H2A	0.9900
S1—O2	1.4842 (7)	C2—H2B	0.9900
N1—C1	1.4712 (12)
N1i—Cu1—N1	91.62 (4)	C1—N1—H1N	109.4 (10)
N1i—Cu1—N2i	85.22 (3)	Cu1—N1—H1N	105.0 (10)
N1—Cu1—N2i	176.81 (3)	C1—N1—H2N	112.3 (12)
N1i—Cu1—N2	176.81 (3)	Cu1—N1—H2N	109.6 (12)
N1—Cu1—N2	85.22 (3)	H1N—N1—H2N	111.3 (14)
N2i—Cu1—N2	97.95 (4)	C2—N2—Cu1	106.36 (5)
N1i—Cu1—O1	92.50 (3)	C2—N2—H3N	110.2 (11)
N1—Cu1—O1	92.50 (3)	Cu1—N2—H3N	112.1 (11)
N2i—Cu1—O1	87.27 (3)	C2—N2—H4N	110.0 (10)
N2—Cu1—O1	87.27 (3)	Cu1—N2—H4N	108.4 (10)
N1i—Cu1—O3ii	92.95 (3)	H3N—N2—H4N	109.7 (14)
N1—Cu1—O3ii	92.95 (3)	N1—C1—C2	107.73 (7)
N2i—Cu1—O3ii	87.59 (3)	N1—C1—H1A	110.2
N2—Cu1—O3ii	87.59 (3)	C2—C1—H1A	110.2
O1—Cu1—O3ii	172.18 (3)	N1—C1—H1B	110.2
O1—S1—O3	108.42 (5)	C2—C1—H1B	110.2
O1—S1—O2i	110.05 (3)	H1A—C1—H1B	108.5
O3—S1—O2i	109.58 (3)	N2—C2—C1	107.97 (7)
O1—S1—O2	110.05 (3)	N2—C2—H2A	110.1
O3—S1—O2	109.59 (3)	C1—C2—H2A	110.1
O2i—S1—O2	109.14 (6)	N2—C2—H2B	110.1
S1—O1—Cu1	125.23 (5)	C1—C2—H2B	110.1
C1—N1—Cu1	108.92 (5)	H2A—C2—H2B	108.4
O3—S1—O1—Cu1	180.0	N2—Cu1—N1—C1	9.25 (6)
O2i—S1—O1—Cu1	60.16 (3)	O1—Cu1—N1—C1	96.30 (6)
O2—S1—O1—Cu1	−60.16 (3)	N1—Cu1—N2—C2	19.71 (6)
N1i—Cu1—O1—S1	−45.86 (2)	N2i—Cu1—N2—C2	−159.89 (4)
N1—Cu1—O1—S1	45.86 (2)	O1—Cu1—N2—C2	−73.03 (6)
N2i—Cu1—O1—S1	−130.95 (2)	Cu1—N1—C1—C2	−35.63 (9)
N2—Cu1—O1—S1	130.95 (2)	Cu1—N2—C2—C1	−44.31 (8)
N1i—Cu1—N1—C1	−171.12 (4)	N1—C1—C2—N2	53.74 (10)

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

Hydrogen-bond geometry (Å, °)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O2	0.858 (16)	2.280 (16)	3.0944 (11)	158.5 (14)
N1—H2N···O3iii	0.839 (17)	2.274 (17)	3.0642 (11)	157.1 (17)
N2—H3N···O2iv	0.845 (17)	2.125 (17)	2.9636 (10)	171.6 (16)
N2—H4N···O2v	0.859 (15)	2.210 (15)	3.0308 (10)	159.7 (14)

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