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Acta Crystallogr Sect E Struct Rep Online. 2010 December 1; 66(Pt 12): o3346–o3347.
Published online 2010 November 27. doi:  10.1107/S1600536810049160
PMCID: PMC3011428

Diacetamidinium sulfate

Abstract

In the crystal structure of the title compound, 2C2H7N2 +·SO4 2−, which contains four cations and two anions in the asymmetric unit, the ions are inter­connected by an extensive hydrogen-bonding system whereby two of the O atoms of sulfate ion are hydrogen-bonded to the amidinium H atoms of two cations, leading to the formation of two eight-membered rings. The two remaining O atoms inter­connect two H atoms of acetamidinium cations, forming an infinite chain. The C(...)N separations within the H2N(...)C(...)NH2 moieties are similar, with an average value of 1.305 (2) Å, which is in good agreement with a delocalization model.

Related literature

For preparation, reactivity and behaviour of similar compounds, see: Jalový et al. (2005 [triangle]); Latypov et al. (1998 [triangle]); Taylor & Ehrhart (1960 [triangle]). For related structures, see: Calov & Jost (1990 [triangle]); Cannon et al. (1976 [triangle]); Emirdag-Eanes & Ibers (2002) [triangle]; Ferretti et al. (2004 [triangle]); Jalový et al. (2009 [triangle]); Tominey et al. (2006 [triangle]).

An external file that holds a picture, illustration, etc.
Object name is e-66-o3346-scheme1.jpg

Experimental

Crystal data

  • 2C2H7N2 +·SO4 2−
  • M r = 214.26
  • Triclinic, An external file that holds a picture, illustration, etc.
Object name is e-66-o3346-efi1.jpg
  • a = 8.0961 (3) Å
  • b = 11.1668 (4) Å
  • c = 11.8821 (6) Å
  • α = 96.199 (4)°
  • β = 105.905 (3)°
  • γ = 105.615 (4)°
  • V = 975.63 (8) Å3
  • Z = 4
  • Mo Kα radiation
  • μ = 0.33 mm−1
  • T = 150 K
  • 0.44 × 0.23 × 0.21 mm

Data collection

  • Bruker–Nonius KappaCCD area-detector diffractometer
  • Absorption correction: Gaussian (Coppens, 1970 [triangle]) T min = 0.915, T max = 0.958
  • 20866 measured reflections
  • 4459 independent reflections
  • 3623 reflections with I > 2σ(I)
  • R int = 0.040

Refinement

  • R[F 2 > 2σ(F 2)] = 0.040
  • wR(F 2) = 0.105
  • S = 1.10
  • 4459 reflections
  • 239 parameters
  • H-atom parameters constrained
  • Δρmax = 0.23 e Å−3
  • Δρmin = −0.46 e Å−3

Data collection: COLLECT (Hooft, 1998 [triangle]) and DENZO (Otwin­owski & Minor, 1997 [triangle]); cell refinement: COLLECT and DENZO; data reduction: COLLECT and DENZO; program(s) used to solve structure: SIR92 (Altomare et al., 1994 [triangle]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 [triangle]); molecular graphics: PLATON (Spek, 2009 [triangle]); software used to prepare material for publication: SHELXL97.

Table 1
Hydrogen-bond geometry (Å, °)

Supplementary Material

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536810049160/rk2242sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810049160/rk2242Isup2.hkl

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

Acknowledgments

The authors thank the Ministry of Education, Youth and Sports of the Czech Republic (within the framework of research project MSM 0021627501) and the Ministry of Industry and Trade of the Czech Republic (within the framework of the research project FR–TI1/127) for financial support of this work.

supplementary crystallographic information

Comment

Acetamidinium sulphate, C4H14N4O4S, (Scheme 1), is a starting material for the synthesis of insensitive explosive 2,2–dinitroethene–1,1–diamine (Latypov et al., 1998; Jalový et al., 2005). It has low hygroscopicity with comparison to commercially available acetamidinium hydrochloride. The title compound was prepared from acetamidinium acetate and equivalent amount of sulfuric acid.

The crystal structure of acetamidinium sulfate has been determined in order to evaluate the degree of association of these ionic species. Two crystallographically independent bisacetamidinium sulfates were found in the unit cell (Fig. 1). The molecular structure of the title compound is made up of two mutually similar acetamidinium units and one sulfate ion. All these ions are interconnected by extensive hydrogen bonding systems where two of the oxygen atoms of sulfate ion (O1 and O2) are bonded to the exo–amidinium hydrogen atoms of two units which leading to the formation of two 8–membered rings (Fig. 2). The S–O distances for these particular oxygen atoms O1 and O2 are slightly elongated in comparison to remaining two oxygen atoms O3 and O4 which form a chain. On the other hand, two remaining oxygen atoms interconnect two endo–hydrogen atoms of acetamidinium units forming thus an infinite chain. The C–N separations within the H2N···C···NH2 fragments are mutually similar with average value of 1.305 (2)Å which is with a good agreement with a delocalization concept of the double bond in H2N-C(CH3)═NH2 cationand the literature data, where the range 1.302–1.312Å was found. The comparison of the title compound with the published structures can be made on the bases of two different criteria. The first, all acetamidinium salts reveal the same geometry and structural parameters of the acetamidinium ion. The second criterion is the type of the supramolecular structure formed. There are large differences between the title compound where the two planar layers of acetamidinium ions are interconnected to the infinite double layer. Other 2D structures are found for the acetamidinium formate (Tominey et al., 2006), dinitromethanide (Jalový et al., 2009), amidinium acetate (Ferretti et al., 2004) with the stairs like layered structure and one of the polymorphs of amidinium (2–hydroxyethoxy)acetate (Ferretti et al., 2004). On the other hand, the second polymorph of amidinium (2–hydroxyethoxy)acetate (Ferretti et al., 2004), acetamidinium tetrazolate (Tominey et al., 2006) and acetamidinium chloride (Cannon et al., 1976) reveal 3D structures with large cavities. There are a couple of related acetamidinium ion containing structures which are of interest as for example bis(acetamidinium) hexafluorosilicate (Calov & Jost, 1990) where the multicentered contacts between acetamidinium hydrogen atoms and fluorine atoms were found and the selenium and rhenium containing cluster compound where the hydrogen contacts of acetamidinium ion with cyano group bonded to the rhenium atoms and a short contact between selenium and nitrogen atoms were found (Emirdag-Eanes et al., 2002).

Experimental

Acetamidinium acetate (1.50 g, 12.7 mmol; Taylor & Ehrhart, 1960) was dissolved in propan–2–ol (15 ml). Sulfuric acid (100%; 0.62 g, 6.3 mmol) was then slowly added. The precipitated product was filtered and washed with fresh propan–2–ol to give 1.15 g (84.6 %) of white solid, m.p. 483–485 K (484-485 K; Jalový et al., 2005). Elementary analysis calc. for C4H14N4O4S: C, 22.42%; H, 6.58%; N, 26.16%; S, 14.96%. Found: C, 23.16%; H, 6.27%; N, 25.98%; S, 15.26%. Spectral characteristic are the same as described previously by Jalový et al., (2005). The crystals suitable for X–ray were prepared by crystallization from methanol by slow cooling of the hot solution.

Refinement

All the hydrogens were discernible in the difference electron density map. However, all the hydrogens were situated into idealized positions and refined riding on their parent C or N atoms, with N—H = 0.86Å, C—H = 0.96Å for methyl, Uiso(H) = 1.2Ueq(N) and Uiso(H) = 1.5Ueq(C) for methyl H atoms, respectively.

Figures

Fig. 1.
View of the title molecule with the atom numbering scheme. Displacement ellipsoids are shown on 50% probability level. The H atoms are presented as a spheres of arbitrary radius.
Fig. 2.
View of the motif of the structure with the hydrogen bonding.

Crystal data

2C2H7N2+·O4S2Z = 4
Mr = 214.26F(000) = 456
Triclinic, P1Dx = 1.459 Mg m3
Hall symbol: -P 1Melting point = 483–485 K
a = 8.0961 (3) ÅMo Kα radiation, λ = 0.71073 Å
b = 11.1668 (4) ÅCell parameters from 20921 reflections
c = 11.8821 (6) Åθ = 1–27.5°
α = 96.199 (4)°µ = 0.33 mm1
β = 105.905 (3)°T = 150 K
γ = 105.615 (4)°Block, colourless
V = 975.63 (8) Å30.44 × 0.23 × 0.21 mm

Data collection

Bruker–Nonius KappaCCD area-detector diffractometer4459 independent reflections
Radiation source: fine–focus sealed tube3623 reflections with I > 2σ(I)
graphiteRint = 0.040
Detector resolution: 9.091 pixels mm-1θmax = 27.5°, θmin = 2.4°
[var phi]– and ω–scans to fill the Ewald sphereh = −10→10
Absorption correction: gaussian (Coppens, 1970)k = −14→14
Tmin = 0.915, Tmax = 0.958l = −15→15
20866 measured reflections

Refinement

Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.040Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.105H-atom parameters constrained
S = 1.10w = 1/[σ2(Fo2) + (0.0486P)2 + 0.6492P] where P = (Fo2 + 2Fc2)/3
4459 reflections(Δ/σ)max < 0.001
239 parametersΔρmax = 0.23 e Å3
0 restraintsΔρmin = −0.46 e Å3

Special details

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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)

xyzUiso*/Ueq
S10.79775 (6)0.46840 (4)0.72331 (4)0.01727 (12)
S20.19510 (6)0.03481 (4)0.78098 (4)0.01627 (12)
O60.16125 (19)0.02135 (13)0.89534 (12)0.0213 (3)
O70.1162 (2)−0.08915 (13)0.69712 (12)0.0239 (3)
O30.71625 (18)0.37497 (12)0.60982 (12)0.0209 (3)
O20.71148 (19)0.42348 (14)0.81242 (12)0.0235 (3)
O40.99312 (18)0.48642 (13)0.76995 (12)0.0219 (3)
O50.11266 (18)0.12598 (12)0.72686 (12)0.0208 (3)
N12−0.0434 (2)0.77755 (16)0.91285 (15)0.0216 (3)
H12A−0.12510.72710.85090.026*
H12B0.01030.85390.90860.026*
O80.39298 (18)0.07972 (14)0.80283 (12)0.0240 (3)
N180.4617 (2)0.13845 (16)0.59125 (15)0.0215 (3)
H18A0.45450.11150.65540.026*
H18B0.55200.20170.59390.026*
N150.3313 (2)0.36087 (16)0.70691 (15)0.0215 (3)
H15A0.44080.39390.75350.026*
H15B0.26100.29510.72050.026*
O10.7676 (2)0.59000 (13)0.70173 (12)0.0242 (3)
N160.3762 (2)0.51104 (15)0.59222 (15)0.0213 (3)
H16A0.48610.54550.63770.026*
H16B0.33430.54210.53150.026*
N11−0.0796 (2)0.62260 (16)1.02350 (15)0.0215 (3)
H11A−0.16180.57040.96280.026*
H11B−0.04930.59901.09070.026*
N130.2530 (2)0.72388 (16)0.79442 (15)0.0225 (4)
H13A0.21780.77670.75370.027*
H13B0.18490.64650.78010.027*
N140.5176 (2)0.87828 (16)0.90289 (15)0.0227 (4)
H14A0.48600.93320.86360.027*
H14B0.62010.90010.95850.027*
C70.3355 (3)0.08310 (17)0.48927 (17)0.0183 (4)
N170.1957 (2)−0.01346 (15)0.48128 (15)0.0215 (3)
H17A0.1850−0.04240.54400.026*
H17B0.1146−0.04800.41320.026*
C30.4094 (3)0.76088 (18)0.87780 (17)0.0195 (4)
C50.2718 (3)0.41071 (17)0.61547 (17)0.0179 (4)
C1−0.0009 (3)0.73845 (18)1.01366 (17)0.0182 (4)
C60.0825 (3)0.3512 (2)0.53533 (19)0.0242 (4)
H6A0.07130.27080.49090.036*
H6B0.05200.40560.48110.036*
H6C0.00200.33900.58220.036*
C40.4675 (3)0.6675 (2)0.9475 (2)0.0314 (5)
H4A0.43600.67351.01970.047*
H4B0.59600.68570.96700.047*
H4C0.40790.58340.90070.047*
C20.1430 (3)0.82735 (19)1.11939 (18)0.0235 (4)
H2A0.25830.81901.12050.035*
H2B0.11890.80741.19110.035*
H2C0.14420.91281.11460.035*
C80.3526 (3)0.1306 (2)0.37894 (18)0.0278 (5)
H8A0.28180.18690.36200.042*
H8B0.30990.06020.31310.042*
H8C0.47710.17530.39070.042*

Atomic displacement parameters (Å2)

U11U22U33U12U13U23
S10.0150 (2)0.0162 (2)0.0149 (2)−0.00007 (17)0.00017 (17)0.00432 (17)
S20.0153 (2)0.0161 (2)0.0141 (2)0.00153 (17)0.00173 (17)0.00533 (16)
O60.0210 (7)0.0234 (7)0.0168 (7)0.0018 (5)0.0056 (5)0.0072 (5)
O70.0275 (8)0.0182 (7)0.0197 (7)0.0040 (6)0.0012 (6)0.0022 (5)
O30.0208 (7)0.0179 (7)0.0167 (6)0.0004 (5)0.0004 (5)0.0026 (5)
O20.0189 (7)0.0289 (8)0.0194 (7)0.0017 (6)0.0048 (6)0.0090 (6)
O40.0154 (7)0.0233 (7)0.0210 (7)0.0006 (5)0.0008 (5)0.0072 (5)
O50.0201 (7)0.0172 (7)0.0211 (7)0.0030 (5)0.0015 (5)0.0079 (5)
N120.0230 (9)0.0174 (8)0.0190 (8)0.0015 (6)0.0028 (7)0.0034 (6)
O80.0158 (7)0.0305 (8)0.0223 (7)0.0027 (6)0.0035 (6)0.0102 (6)
N180.0202 (8)0.0201 (8)0.0193 (8)−0.0008 (6)0.0059 (7)0.0036 (6)
N150.0186 (8)0.0202 (8)0.0233 (8)0.0024 (6)0.0052 (7)0.0083 (7)
O10.0267 (8)0.0163 (7)0.0222 (7)0.0029 (6)−0.0001 (6)0.0041 (5)
N160.0206 (8)0.0210 (8)0.0187 (8)0.0035 (7)0.0020 (7)0.0081 (6)
N110.0203 (8)0.0217 (8)0.0178 (8)0.0029 (7)0.0010 (7)0.0063 (6)
N130.0194 (8)0.0176 (8)0.0252 (9)0.0022 (6)0.0026 (7)0.0043 (7)
N140.0187 (8)0.0224 (8)0.0209 (8)0.0021 (7)0.0003 (7)0.0049 (7)
C70.0184 (9)0.0173 (9)0.0202 (9)0.0067 (7)0.0068 (7)0.0038 (7)
N170.0188 (8)0.0229 (8)0.0167 (8)0.0003 (7)0.0022 (6)0.0036 (6)
C30.0198 (9)0.0209 (9)0.0186 (9)0.0063 (7)0.0076 (7)0.0035 (7)
C50.0192 (9)0.0161 (9)0.0181 (9)0.0058 (7)0.0064 (7)0.0009 (7)
C10.0158 (9)0.0203 (9)0.0197 (9)0.0068 (7)0.0064 (7)0.0032 (7)
C60.0181 (10)0.0256 (10)0.0255 (10)0.0040 (8)0.0043 (8)0.0049 (8)
C40.0303 (12)0.0270 (11)0.0352 (12)0.0107 (9)0.0045 (10)0.0099 (9)
C20.0195 (10)0.0243 (10)0.0215 (10)0.0044 (8)0.0028 (8)−0.0003 (8)
C80.0304 (12)0.0301 (11)0.0216 (10)0.0045 (9)0.0096 (9)0.0083 (8)

Geometric parameters (Å, °)

S1—O41.4743 (14)N13—H13A0.8600
S1—O31.4766 (14)N13—H13B0.8600
S1—O11.4795 (14)N14—C31.315 (3)
S1—O21.4806 (14)N14—H14A0.8600
S2—O51.4722 (14)N14—H14B0.8600
S2—O61.4732 (13)C7—N171.309 (2)
S2—O71.4813 (14)C7—C81.493 (3)
S2—O81.4822 (14)N17—H17A0.8600
N12—C11.308 (3)N17—H17B0.8600
N12—H12A0.8600C3—C41.494 (3)
N12—H12B0.8600C5—C61.487 (3)
N18—C71.309 (3)C1—C21.492 (3)
N18—H18A0.8600C6—H6A0.9600
N18—H18B0.8600C6—H6B0.9600
N15—C51.308 (3)C6—H6C0.9600
N15—H15A0.8600C4—H4A0.9600
N15—H15B0.8600C4—H4B0.9600
N16—C51.316 (2)C4—H4C0.9600
N16—H16A0.8600C2—H2A0.9600
N16—H16B0.8600C2—H2B0.9600
N11—C11.313 (3)C2—H2C0.9600
N11—H11A0.8600C8—H8A0.9600
N11—H11B0.8600C8—H8B0.9600
N13—C31.303 (3)C8—H8C0.9600
O4—S1—O3110.00 (8)C7—N17—H17A120.1
O4—S1—O1110.05 (8)C7—N17—H17B119.9
O3—S1—O1108.83 (8)H17A—N17—H17B120.0
O4—S1—O2109.08 (8)N13—C3—N14121.98 (18)
O3—S1—O2110.04 (8)N13—C3—C4119.16 (19)
O1—S1—O2108.83 (9)N14—C3—C4118.87 (19)
O5—S2—O6110.39 (8)N15—C5—N16121.47 (18)
O5—S2—O7108.65 (8)N15—C5—C6119.04 (17)
O6—S2—O7110.07 (8)N16—C5—C6119.49 (17)
O5—S2—O8109.79 (8)N12—C1—N11121.67 (18)
O6—S2—O8108.87 (8)N12—C1—C2119.00 (17)
O7—S2—O8109.07 (9)N11—C1—C2119.31 (17)
C1—N12—H12A120.1C5—C6—H6A109.5
C1—N12—H12B119.9C5—C6—H6B109.5
H12A—N12—H12B120.0H6A—C6—H6B109.5
C7—N18—H18A120.1C5—C6—H6C109.5
C7—N18—H18B119.8H6A—C6—H6C109.5
H18A—N18—H18B120.1H6B—C6—H6C109.5
C5—N15—H15A120.0C3—C4—H4A109.5
C5—N15—H15B120.1C3—C4—H4B109.5
H15A—N15—H15B119.9H4A—C4—H4B109.5
C5—N16—H16A120.1C3—C4—H4C109.5
C5—N16—H16B119.9H4A—C4—H4C109.5
H16A—N16—H16B120.0H4B—C4—H4C109.5
C1—N11—H11A120.0C1—C2—H2A109.5
C1—N11—H11B120.0C1—C2—H2B109.5
H11A—N11—H11B120.0H2A—C2—H2B109.5
C3—N13—H13A120.1C1—C2—H2C109.5
C3—N13—H13B119.9H2A—C2—H2C109.5
H13A—N13—H13B120.0H2B—C2—H2C109.5
C3—N14—H14A120.0C7—C8—H8A109.5
C3—N14—H14B120.0C7—C8—H8B109.5
H14A—N14—H14B120.0H8A—C8—H8B109.5
N18—C7—N17121.79 (18)C7—C8—H8C109.5
N18—C7—C8119.04 (18)H8A—C8—H8C109.5
N17—C7—C8119.17 (18)H8B—C8—H8C109.5

Hydrogen-bond geometry (Å, °)

D—H···AD—HH···AD···AD—H···A
N12—H12A···O1i0.862.022.838 (2)158
N12—H12A···S1i0.862.933.6038 (17)136
N12—H12B···O6ii0.861.992.843 (2)172
N12—H12B···S2ii0.862.983.7523 (17)150
N18—H18A···O80.861.992.826 (2)164
N18—H18A···S20.862.903.6006 (17)140
N18—H18B···O30.861.992.823 (2)164
N15—H15A···O20.862.032.841 (2)157
N15—H15A···S10.862.923.5841 (17)136
N15—H15B···S20.863.013.7829 (17)150
N15—H15B···O50.861.972.817 (2)169
N16—H16A···O10.862.092.915 (2)160
N16—H16A···S10.862.853.5245 (18)137
N16—H16B···O3iii0.862.002.852 (2)170
N16—H16B···S1iii0.862.903.6821 (17)152
N11—H11A···O2i0.862.102.922 (2)161
N11—H11A···S1i0.862.843.5335 (17)138
N11—H11B···O4iv0.862.012.856 (2)170
N11—H11B···S1iv0.862.883.6657 (17)152
N13—H13A···O7ii0.861.992.826 (2)165
N13—H13A···S2ii0.862.933.6408 (18)142
N13—H13B···O4i0.861.992.835 (2)165
N14—H14A···O8ii0.862.092.938 (2)167
N14—H14A···S2ii0.862.873.5920 (18)143
N14—H14B···O6iv0.862.022.863 (2)167
N14—H14B···S2iv0.862.963.6973 (17)145
N17—H17A···O70.862.122.964 (2)167
N17—H17B···S2v0.862.953.7158 (17)149
N17—H17B···O5v0.862.012.861 (2)168
N17—H17B···S2v0.862.953.7158 (17)149

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

Footnotes

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: RK2242).

References

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