supplementary materials


bt5731 scheme

Acta Cryst. (2012). E68, m47-m48    [ doi:10.1107/S1600536811051658 ]

trans-Bis(ethylenediamine-[kappa]2N,N')bis(6-methyl-2,2,4-trioxo-3,4-dihydro-1,2[lambda]6,3-oxathiazin-3-ido-[kappa]N)copper(II)

N. Dege, G. Demirtas and H. Içbudak

Abstract top

In the crystal structure of the title compound, [Cu(C4H4NO4S)2(C2H8N2)2], the Cu2+ ion resides on a centre of symmetry. The environment of Cu2+ ion is a distorted octahedron. The axial bond lengths between the CuII ion and the N atoms are considerably longer than the equatorial bond distances between the CuII ion and the N atoms of the ethylenediamine ligand as a consequence of the Jahn-Teller effect. The molecular conformation is stabilized by intramolecular N-H...O hydrogen bonds. In the crystal, molecules are connected by intermolecular N-H...O hydrogen bonds into chains running along the a axis.

Comment top

Clauss and Jensen discovered acesulfame (Clauss & Jensen, 1973). Acesulfame (acs), (C4H5SO4N), is systematically named 6-methyl-1,2,3-oxathiazin-4(3H)-one 2,2-dioxide and an oxathiazinone dioxide. It, meanwhile, is known as 6-methyl-3,4-dihydro-1,2,3-oxathiazin-4-one 2,2-dioxide or acetosulfam. Acesulfame has been widely used as a non-caloric artificial sweetener (Duffy et al. 1998; O'Brien Nabors, 2001) since 1988, after the FDA (US Food and Drug Administration) granted approval. Acesulfame which is nonnutritive sweetener have been widely used by the food industries to replace sugars in foods. Acesulfame is without calories and it is not digested, accumulated and changed in the human metabolism and quickly excreted from the body (Duffy et al., 1998; O'Brien Nabors, 2001). Furthermore, acesulfam K can withstand high cooking temperature (Duffy et al., 1998). The artificial sweetener acesulfame has not only biological importance but also interest chemical properties. Because acesulfame ion (acs) has potential donor atoms as the imino nitrogen, ring oxygen, one carbonyl and two sulfonyl O atoms, which can be utilized in forming coordination bonds with different metal ions (İçbudak et al., 2006).

The crystal structures of acesulfame and its metal complexes have been reported previously (Beck et al., 1985; Bulut et al., 2005; Cavicchioli et al., 2010; İçbudak et al., 2005a; İçbudak et al., 2006; İçbudak et al., 2007b; Şahin et al., 2009; Şahin et al., 2010; Velaga et al., 2010). Furthermore, NMR (Beck et al., 1985), electronic (İçbudak et al., 2006; İçbudak et al., 2007a; İçbudak et al., 2007b), IR (Beck et al., 1985; İçbudak et al., 2006; İçbudak et al., 2007a; İçbudak et al., 2007b), mass (İçbudak et al. 2005b) spectroscopies, thermal analysis (İçbudak et al., 2005b; İçbudak et al., 2006; İçbudak et al., 2007a; İçbudak et al., 2007b), magnetic susceptibility (İçbudak et al., 2006; İçbudak et al., 2007a), conductivity (İçbudak et al., 2007b) studies have been performed on the metal complexes of acesulme. In addition, the stability belong to different form of the acesulfame have being studied (Velaga et al., 2010).

Here, we report trans-bis(acesulfamato-N)bis(ethylenediamine-N,N')copper(II) coplex as shown Fig. 1. In the crystal structure, Cu2+ ion is six-coordination by six N atoms from two ethylenediamine and two acesulfamato ligands in a octahedron coordination geometry. Similarly, the Cu2+ complexes in literature had been reported in octahedron coordination geometry (Bulut et al., 2005; İçbudak et al., 2007b; Pariya et al., 1998a; Pariya et al., 1998b; Şahin et al., 2010). The bond distances between Cu2+ and N atoms for the Cu1—N1, Cu1—N2 and Cu1—N3 were found as 2.7432 (15) Å, 2.0091 (15) Å and 2.0103 (14) Å, respectively. As can be seen, the Cu1—N1 bond distance longer than the Cu1—N2 and Cu1—N3 bond distances and this is called as the Jahn-Teller effect (Jahn & Teller, 1937). Cu(II) with d9 electronic configuration is Jahn-Teller active in an octahedron coordination sphere. Because of odd d electron occupies one of the d-orbitals, crystal structure has structural flexibility (Kozlevčar et al., 2006). The crystal structure reported by (Şahin et al., 2010) is similarly the our crystal structure with Jahn-Teller effect. The bond distance between N atoms in axial positions and Cu2+ ion had been reported as 2.7175 (16) Å by (Şahin et al., 2010). The bond distances of some crystal structures that has Jahn-Teller effect in literature are given in Table 3. Because of the N1—Cu1—N2 and N1—Cu1—N3 bond angles are 86.96 (5)° and 87.86 (5)°, repectively, the ethylenediamine group in equatorial plane and acesulfamato ligand axial position are almost perpendicular to each other. Some of the bond distances and bond angles belong to crystal structure are given in Table 1.

The title compound, trans-bis(acesulfamato-N)bis(ethylenediamine-N,N')copper(II), has intramolecular and intermolecular N—H···O hydrogen bonds. These hydrogen bonds play an important role for packing of molecules. The intra- and intermolecular hydrogen bonds are occurred via the Ocarbonyl and Osuphonyl of acesulfamoto ligand which are donor atoms. Inramolecular N3—H3B···O4 and N3—H3A···O2iii [symmetry code iii: -x + 1, -y + 1, -z + 1] hydrogen bonds are between the N atoms of ethylenediamine coordinated with the Cu2+ ion and the Osulfonyl and Ocarbonyl of acesulfamato ligand. The geometric parameters of these hydrogen bonds are 0.82 (2) Å, 2.21 (82) Å, 2.905 (2) Å, 144 (2)° and 0.87 (2) Å, 2.21 (2) Å, 2.973 (2) Å, 147.5 (19)°, respectively. The intermolecular hydrogen bonds are between the N atoms of ethylenediamine and the Ocarbonyl and other Osulfonyl atoms of acesulfamato ligand. The details of hydrogen bonds are shown in Table 2. In the crystal structure, the N2—H2B···O1 intermolecular hydrogen bonds along the [001] produce R22(12) motifs. Similarly, the N2—H2A···O4 intermolecular hydrogen bonds along the [100] create R22(12) ring motifs. The two-dimensional sheet are produced by the combination of the N—H···O intermolecular hydrogen bonds at the ac-plane as shown Fig. 2.

Related literature top

For background to acesulfame [systematic name: 6-methyl-1,2,3-oxathiazin-4(3H)-one 2,2-dioxide], see: Clauss & Jensen (1973); Duffy & Anderson (1998); O'Brien Nabors (2001); İçbudak et al. (2006) For the crystal structures of acesulfame and its metal complexes, see: Beck et al. (1985); Bulut et al. (2005); Cavicchioli et al. (2010); İçbudak et al. (2005a, 2006, 2007b); Şahin et al. (2009, 2010); Velaga et al. (2010) and for spectroscopic, thermal analysis, magnetic susceptibility and conductivity studies on metal complexes of acesulme, see: Beck et al. (1985); İçbudak et al. (2005a,b, 2006, 2007a,b). For Cu2+ complexes with an octahedron coordination geometry, see: Bulut et al. (2005); İçbudak et al. (2007b); Pariya et al. (1998a,b); Şahin et al. (2010). For the Jahn–Teller effect, see: Jahn & Teller (1937). For the structural flexibility owing to the electronic configuration, see: Kozlevčar et al. (2006). For [please specify], see: Petric et al. (1998);

Experimental top

The complex was prepared upon treatment of 1 mmol [Cu(acs)2(H2O)] in 50 ml e thanol with 2 mmol e thylenediamine in 50 ml e thanol by stirring for 2 h at 50 C temperature. After cooling the reaction mixture to room temperature, the formed violet crystals were filtered, washed with alcohol and acetone, and dried in vacuum.

Refinement top

H atoms attached to C atoms were positioned geometrically [C—H=0.930, 0.960 or 0.970 Å] and treated as riding with Uiso(H)=1.2Ueq(C) and 1.5Ueq(C). Other H atoms were located in a difference map and refined freely.

Computing details top

Data collection: X-AREA (Stoe & Cie, 2002); cell refinement: X-AREA (Stoe & Cie, 2002); data reduction: X-RED (Stoe & Cie, 2002); program(s) used to solve structure: WinGX (Farrugia, 1997) and SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997)and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing the atomic numbering scheme. Displacement ellipsoids are drawn at the 50% probability level.
[Figure 2] Fig. 2. The two-dimensional sheet structure of the title compound with the hydrogen bonds.
trans-Bis(ethylenediamine-κ2N,N')bis(6-methyl-2,2,4- trioxo-3,4-dihydro-1,2λ6,3-oxathiazin-3-ido-κN)copper(II) top
Crystal data top
[Cu(C4H4NO4S)2(C2H8N2)2]F(000) = 526
Mr = 508.03Dx = 1.640 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 28030 reflections
a = 6.9853 (3) Åθ = 2.3–28.0°
b = 17.5355 (6) ŵ = 1.32 mm1
c = 8.4092 (4) ÅT = 296 K
β = 93.017 (3)°Prism, violet
V = 1028.62 (7) Å30.75 × 0.47 × 0.32 mm
Z = 2
Data collection top
Stoe IPDS 2
diffractometer
2023 independent reflections
Radiation source: fine-focus sealed tube1865 reflections with I > 2σ(I)
graphiteRint = 0.036
w–scan rotationθmax = 26.0°, θmin = 2.3°
Absorption correction: integration
(X-RED32; Stoe & Cie, 2002)
h = 88
Tmin = 0.438, Tmax = 0.678k = 2121
14620 measured reflectionsl = 1010
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.024Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.065H atoms treated by a mixture of independent and constrained refinement
S = 1.09 w = 1/[σ2(Fo2) + (0.0309P)2 + 0.3289P]
where P = (Fo2 + 2Fc2)/3
2023 reflections(Δ/σ)max = 0.001
150 parametersΔρmax = 0.23 e Å3
0 restraintsΔρmin = 0.25 e Å3
Crystal data top
[Cu(C4H4NO4S)2(C2H8N2)2]V = 1028.62 (7) Å3
Mr = 508.03Z = 2
Monoclinic, P21/cMo Kα radiation
a = 6.9853 (3) ŵ = 1.32 mm1
b = 17.5355 (6) ÅT = 296 K
c = 8.4092 (4) Å0.75 × 0.47 × 0.32 mm
β = 93.017 (3)°
Data collection top
Stoe IPDS 2
diffractometer
2023 independent reflections
Absorption correction: integration
(X-RED32; Stoe & Cie, 2002)
1865 reflections with I > 2σ(I)
Tmin = 0.438, Tmax = 0.678Rint = 0.036
14620 measured reflectionsθmax = 26.0°
Refinement top
R[F2 > 2σ(F2)] = 0.024H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.065Δρmax = 0.23 e Å3
S = 1.09Δρmin = 0.25 e Å3
2023 reflectionsAbsolute structure: ?
150 parametersFlack parameter: ?
0 restraintsRogers parameter: ?
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
xyzUiso*/Ueq
C10.1200 (3)0.55390 (12)0.7619 (2)0.0473 (4)
C20.0228 (3)0.59733 (13)0.8823 (2)0.0526 (5)
H20.09160.57810.91770.063*
C30.0877 (3)0.66195 (12)0.9434 (2)0.0483 (4)
C40.0106 (3)0.71462 (15)1.0516 (3)0.0697 (6)
H4A0.14280.70011.05570.105*
H4B0.00270.76591.01230.105*
H4C0.05020.71181.15650.105*
C50.5868 (3)0.36713 (11)0.6731 (2)0.0508 (5)
H5A0.62840.34030.76970.061*
H5B0.64710.34380.58390.061*
C60.3715 (3)0.36387 (11)0.6486 (3)0.0539 (5)
H6A0.33100.31190.62570.065*
H6B0.31230.38050.74440.065*
Cu10.50000.50000.50000.03988 (11)
N10.2955 (2)0.57689 (9)0.71898 (19)0.0463 (4)
N20.6387 (2)0.44831 (9)0.6856 (2)0.0435 (3)
N30.3116 (2)0.41394 (9)0.51456 (19)0.0404 (3)
O10.5067 (2)0.59346 (10)0.96415 (19)0.0653 (4)
O20.5347 (2)0.68003 (9)0.7441 (2)0.0699 (5)
O30.26382 (19)0.69080 (8)0.90616 (17)0.0539 (3)
O40.0388 (2)0.49923 (9)0.6937 (2)0.0673 (4)
S10.41531 (6)0.63171 (3)0.83179 (6)0.04469 (13)
H2A0.755 (3)0.4555 (13)0.691 (3)0.054 (6)*
H2B0.602 (3)0.4650 (14)0.776 (3)0.055 (6)*
H3A0.307 (3)0.3881 (13)0.429 (3)0.053 (6)*
H3B0.207 (3)0.4339 (13)0.526 (3)0.056 (6)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0385 (9)0.0561 (11)0.0471 (10)0.0003 (8)0.0002 (8)0.0054 (8)
C20.0387 (9)0.0678 (13)0.0519 (11)0.0002 (9)0.0087 (8)0.0065 (10)
C30.0449 (10)0.0571 (11)0.0431 (10)0.0123 (9)0.0050 (8)0.0006 (8)
C40.0639 (14)0.0801 (16)0.0662 (13)0.0215 (12)0.0136 (11)0.0153 (12)
C50.0590 (12)0.0398 (9)0.0528 (11)0.0035 (8)0.0063 (9)0.0067 (8)
C60.0591 (12)0.0445 (10)0.0572 (12)0.0135 (9)0.0039 (9)0.0123 (9)
Cu10.03489 (16)0.03563 (17)0.04820 (19)0.00665 (12)0.00646 (12)0.00794 (12)
N10.0406 (8)0.0500 (8)0.0490 (8)0.0035 (7)0.0078 (6)0.0126 (7)
N20.0373 (8)0.0447 (8)0.0481 (9)0.0025 (7)0.0033 (7)0.0033 (7)
N30.0376 (8)0.0395 (8)0.0440 (9)0.0044 (6)0.0015 (6)0.0016 (7)
O10.0569 (9)0.0708 (10)0.0666 (9)0.0108 (7)0.0126 (7)0.0071 (8)
O20.0744 (10)0.0541 (8)0.0844 (11)0.0224 (8)0.0346 (9)0.0203 (8)
O30.0539 (8)0.0445 (7)0.0645 (9)0.0039 (6)0.0136 (7)0.0125 (6)
O40.0424 (8)0.0831 (11)0.0769 (10)0.0151 (7)0.0067 (7)0.0326 (9)
S10.0409 (2)0.0421 (2)0.0517 (3)0.00205 (18)0.00779 (19)0.01057 (19)
Geometric parameters (Å, °) top
C1—O41.239 (2)C6—H6B0.9700
C1—N11.357 (2)Cu1—N12.7434 (15)
C1—C21.462 (3)Cu1—N1i2.7434 (15)
C2—C31.315 (3)Cu1—N22.0090 (16)
C2—H20.9300Cu1—N2i2.0090 (16)
C3—O31.381 (2)Cu1—N32.0101 (14)
C3—C41.489 (3)Cu1—N3i2.0102 (14)
C4—H4A0.9600N1—S11.5624 (15)
C4—H4B0.9600N2—H2A0.82 (2)
C4—H4C0.9600N2—H2B0.87 (2)
C5—N21.471 (2)N3—H3A0.85 (2)
C5—C61.509 (3)N3—H3B0.82 (2)
C5—H5A0.9700O1—S11.4218 (16)
C5—H5B0.9700O2—S11.4220 (15)
C6—N31.472 (2)O3—S11.6292 (13)
C6—H6A0.9700
O4—C1—N1120.27 (17)N1—Cu1—N387.84 (5)
O4—C1—C2120.39 (17)N2—Cu1—N2i180.0
N1—C1—C2119.23 (17)N2—Cu1—N384.51 (7)
C3—C2—C1123.79 (18)N2i—Cu1—N395.49 (7)
C3—C2—H2118.1N2—Cu1—N3i95.49 (7)
C1—C2—H2118.1N2i—Cu1—N3i84.51 (7)
C2—C3—O3121.33 (17)N3—Cu1—N3i180.00 (6)
C2—C3—C4127.8 (2)C1—N1—S1118.93 (13)
O3—C3—C4110.88 (19)C5—N2—Cu1105.92 (12)
C3—C4—H4A109.5C5—N2—H2A113.1 (16)
C3—C4—H4B109.5Cu1—N2—H2A114.0 (16)
H4A—C4—H4B109.5C5—N2—H2B107.8 (16)
C3—C4—H4C109.5Cu1—N2—H2B112.0 (15)
H4A—C4—H4C109.5H2A—N2—H2B104 (2)
H4B—C4—H4C109.5C6—N3—Cu1109.52 (11)
N2—C5—C6106.65 (15)C6—N3—H3A109.1 (15)
N2—C5—H5A110.4Cu1—N3—H3A110.4 (15)
C6—C5—H5A110.4C6—N3—H3B112.7 (16)
N2—C5—H5B110.4Cu1—N3—H3B106.0 (16)
C6—C5—H5B110.4H3A—N3—H3B109 (2)
H5A—C5—H5B108.6C3—O3—S1117.28 (12)
N3—C6—C5108.84 (15)O1—S1—O2115.84 (11)
N3—C6—H6A109.9O1—S1—N1112.91 (10)
C5—C6—H6A109.9O2—S1—N1111.20 (9)
N3—C6—H6B109.9O1—S1—O3105.87 (9)
C5—C6—H6B109.9O2—S1—O3103.33 (8)
H6A—C6—H6B108.3N1—S1—O3106.64 (8)
N1—Cu1—N286.97 (6)
O4—C1—C2—C3170.1 (2)N2—Cu1—N3—C61.51 (14)
N1—C1—C2—C36.0 (3)N2i—Cu1—N3—C6178.49 (14)
C1—C2—C3—O35.2 (3)C2—C3—O3—S118.8 (2)
C1—C2—C3—C4172.3 (2)C4—C3—O3—S1163.28 (15)
N2—C5—C6—N352.2 (2)C1—N1—S1—O178.40 (17)
O4—C1—N1—S1165.20 (17)C1—N1—S1—O2149.42 (16)
C2—C1—N1—S118.7 (3)C1—N1—S1—O337.46 (18)
C6—C5—N2—Cu149.01 (18)C3—O3—S1—O182.80 (15)
N3—Cu1—N2—C526.67 (13)C3—O3—S1—O2154.99 (15)
N3i—Cu1—N2—C5153.33 (13)C3—O3—S1—N137.68 (16)
C5—C6—N3—Cu129.1 (2)
Symmetry codes: (i) −x+1, −y+1, −z+1.
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N3—H3B···O40.82 (2)2.20 (2)2.905 (2)143 (2)
N2—H2A···O4ii0.82 (2)2.13 (2)2.931 (2)167 (2)
N2—H2B···O1iii0.87 (2)2.57 (2)3.250 (2)137 (2)
N3—H3A···O2i0.85 (2)2.23 (2)2.974 (2)147 (2)
Symmetry codes: (ii) x+1, y, z; (iii) −x+1, −y+1, −z+2; (i) −x+1, −y+1, −z+1.
Table 1
Selected geometric parameters (Å)
top
Cu1—N12.7434 (15)Cu1—N32.0101 (14)
Cu1—N22.0090 (16)
Table 2
Hydrogen-bond geometry (Å, °)
top
D—H···AD—HH···AD···AD—H···A
N3—H3B···O40.82 (2)2.20 (2)2.905 (2)143 (2)
N2—H2A···O4i0.82 (2)2.13 (2)2.931 (2)167 (2)
N2—H2B···O1ii0.87 (2)2.57 (2)3.250 (2)137 (2)
N3—H3A···O2iii0.85 (2)2.23 (2)2.974 (2)147 (2)
Symmetry codes: (i) x+1, y, z; (ii) −x+1, −y+1, −z+2; (iii) −x+1, −y+1, −z+1.
Table 3
Comparision Cu—N,O bond distance (Å) in related compounds
top
CompoundCu—N, O (equatorial)Cu—N, O (axial)References
[Cu(C4H4NO4S)2(C2H8N2)2]2.0092 (16), 2.0103 (15)2.7434 (15)This work
[Cu(C4H4NO4S)2(C6H14N2)2]2.0077 (17), 2.0036 (18)2.7175 (16)Şahin et al. (2010)
[Cu(C4H12N2)2(H2O)2](C4H4NO4S)2'2.035 (2), 2.051 (2)1.245 (3), 2.479 (2)İçbudak et al. (2007b)
[Cu(C4H4NO4S)2(C4H5N3)2]2.0046 (16), 2.0107 (13)2.4597 (16)Bulut et al. (2005)
C12H32Cl2N4O2Cu2.044 (2), 2.027 (3)2.590 (2)Pariya et al. (1998a)
C12H28N6O6Cu1.990 (4), 2.006 (4)2.620 (3)Pariya et al., 1998a
Cu(O2CC8H17)2(NH2C2H4OH)21.999 (3), 2.009 (2)2.477 (2)Petric et al. (1998)
Acknowledgements top

The authors thank the Ondokuz Mayis University Research Fund for financial support.

references
References top

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