Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803017380/bt6323sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536803017380/bt6323Isup2.hkl |
CCDC reference: 222861
5 ml of 0.1 M `H2SeO3' (dissolved SeO2) and 5 ml of 0.1 M cyanoguanidine (C2H4N4) were mixed, resulting in a clear solution. Rod- and block-shaped crystals of (I) grew as the water evaporated over the course of a few days. The cyanoguanidine was transformed to guanylurea by slow acid hydrolysis.
Atom H8 was found in a difference map and refined by riding in its as-found position. H atoms bonded to nitrogen were placed in calculated positions [d(N—H) = 0.86 Å] and refined by riding. The constraint Uiso(H) = 1.2Ueq(parent atom) was applied in all cases.
Data collection: SMART (Bruker, 1999); cell refinement: SAINT (Bruker, 1999); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97; molecular graphics: ORTEP-3 (Farrugia, 1997) and ATOMS (Shape Software, 1999); software used to prepare material for publication: SHELXL97.
C2H7N4O+·HSeO3− | Z = 2 |
Mr = 231.08 | F(000) = 228 |
Triclinic, P1 | Dx = 2.048 Mg m−3 |
a = 6.7643 (4) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 7.9045 (5) Å | Cell parameters from 2368 reflections |
c = 8.2612 (5) Å | θ = 2.8–32.5° |
α = 63.021 (1)° | µ = 4.99 mm−1 |
β = 81.414 (1)° | T = 293 K |
γ = 72.200 (1)° | Block, colourless |
V = 374.77 (4) Å3 | 0.45 × 0.35 × 0.30 mm |
Bruker SMART1000 CCD diffractometer | 2591 independent reflections |
Radiation source: fine-focus sealed tube | 2259 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.016 |
ω scans | θmax = 32.5°, θmin = 2.8° |
Absorption correction: multi-scan (SADABS; Bruker, 1999) | h = −10→10 |
Tmin = 0.143, Tmax = 0.224 | k = −11→7 |
3843 measured reflections | l = −12→12 |
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)] = 0.031 | Hydrogen site location: geom (O-H) and calc (N-H) |
wR(F2) = 0.078 | H-atom parameters constrained |
S = 1.01 | w = 1/[σ2(Fo2) + (0.0491P)2] where P = (Fo2 + 2Fc2)/3 |
2591 reflections | (Δ/σ)max = 0.001 |
100 parameters | Δρmax = 1.00 e Å−3 |
0 restraints | Δρmin = −0.66 e Å−3 |
C2H7N4O+·HSeO3− | γ = 72.200 (1)° |
Mr = 231.08 | V = 374.77 (4) Å3 |
Triclinic, P1 | Z = 2 |
a = 6.7643 (4) Å | Mo Kα radiation |
b = 7.9045 (5) Å | µ = 4.99 mm−1 |
c = 8.2612 (5) Å | T = 293 K |
α = 63.021 (1)° | 0.45 × 0.35 × 0.30 mm |
β = 81.414 (1)° |
Bruker SMART1000 CCD diffractometer | 2591 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 1999) | 2259 reflections with I > 2σ(I) |
Tmin = 0.143, Tmax = 0.224 | Rint = 0.016 |
3843 measured reflections |
R[F2 > 2σ(F2)] = 0.031 | 0 restraints |
wR(F2) = 0.078 | H-atom parameters constrained |
S = 1.01 | Δρmax = 1.00 e Å−3 |
2591 reflections | Δρmin = −0.66 e Å−3 |
100 parameters |
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. |
x | y | z | Uiso*/Ueq | ||
Se1 | 0.46138 (3) | 0.22877 (3) | 0.59621 (3) | 0.02838 (8) | |
O1 | 0.5058 (3) | 0.3655 (3) | 0.3802 (2) | 0.0374 (4) | |
O2 | 0.2742 (3) | 0.1347 (2) | 0.5863 (2) | 0.0370 (3) | |
O3 | 0.6765 (3) | 0.0192 (3) | 0.6524 (3) | 0.0456 (4) | |
H8 | 0.6887 | −0.0448 | 0.5726 | 0.055* | |
O4 | −0.1792 (2) | 0.6594 (3) | 0.0737 (2) | 0.0421 (4) | |
N1 | −0.0675 (3) | 0.4162 (3) | 0.3471 (3) | 0.0375 (4) | |
H1 | −0.1853 | 0.3888 | 0.3756 | 0.045* | |
H2 | 0.0334 | 0.3503 | 0.4224 | 0.045* | |
N2 | 0.1542 (3) | 0.5944 (3) | 0.1572 (2) | 0.0311 (4) | |
H3 | 0.2431 | 0.5226 | 0.2430 | 0.037* | |
N3 | 0.0864 (3) | 0.8605 (3) | −0.1300 (3) | 0.0370 (4) | |
H4 | 0.1293 | 0.9478 | −0.2251 | 0.044* | |
H5 | −0.0406 | 0.8570 | −0.1221 | 0.044* | |
N4 | 0.4101 (3) | 0.7369 (3) | −0.0081 (3) | 0.0414 (5) | |
H6 | 0.4543 | 0.8237 | −0.1026 | 0.050* | |
H7 | 0.4931 | 0.6526 | 0.0797 | 0.050* | |
C1 | 0.2143 (3) | 0.7331 (3) | 0.0024 (3) | 0.0282 (4) | |
C2 | −0.0415 (3) | 0.5601 (3) | 0.1869 (3) | 0.0294 (4) |
U11 | U22 | U33 | U12 | U13 | U23 | |
Se1 | 0.03106 (12) | 0.02730 (11) | 0.02449 (11) | −0.01114 (8) | −0.00084 (7) | −0.00710 (8) |
O1 | 0.0357 (8) | 0.0368 (9) | 0.0298 (8) | −0.0181 (7) | −0.0015 (6) | −0.0006 (6) |
O2 | 0.0345 (8) | 0.0369 (8) | 0.0381 (8) | −0.0193 (7) | 0.0035 (6) | −0.0101 (7) |
O3 | 0.0421 (10) | 0.0418 (10) | 0.0448 (10) | 0.0037 (8) | −0.0196 (8) | −0.0158 (8) |
O4 | 0.0246 (7) | 0.0523 (11) | 0.0352 (8) | −0.0151 (7) | −0.0062 (6) | −0.0024 (8) |
N1 | 0.0312 (9) | 0.0384 (10) | 0.0322 (9) | −0.0159 (8) | −0.0016 (7) | −0.0019 (8) |
N2 | 0.0226 (8) | 0.0364 (10) | 0.0249 (8) | −0.0104 (7) | −0.0044 (6) | −0.0025 (7) |
N3 | 0.0285 (9) | 0.0403 (10) | 0.0299 (9) | −0.0143 (8) | −0.0052 (7) | −0.0002 (8) |
N4 | 0.0257 (9) | 0.0519 (12) | 0.0376 (10) | −0.0176 (9) | −0.0023 (7) | −0.0066 (9) |
C1 | 0.0247 (9) | 0.0321 (10) | 0.0257 (9) | −0.0104 (8) | −0.0014 (7) | −0.0086 (8) |
C2 | 0.0253 (9) | 0.0320 (10) | 0.0272 (9) | −0.0103 (8) | −0.0002 (7) | −0.0081 (8) |
Se1—O1 | 1.6523 (15) | N2—C2 | 1.396 (3) |
Se1—O2 | 1.6807 (16) | N2—H3 | 0.8600 |
Se1—O3 | 1.7626 (17) | N3—C1 | 1.308 (3) |
O3—H8 | 0.9787 | N3—H4 | 0.8600 |
O4—C2 | 1.227 (3) | N3—H5 | 0.8600 |
N1—C2 | 1.328 (3) | N4—C1 | 1.323 (3) |
N1—H1 | 0.8600 | N4—H6 | 0.8600 |
N1—H2 | 0.8600 | N4—H7 | 0.8600 |
N2—C1 | 1.359 (3) | ||
O1—Se1—O2 | 103.10 (8) | C1—N3—H5 | 120.0 |
O1—Se1—O3 | 102.92 (9) | H4—N3—H5 | 120.0 |
O2—Se1—O3 | 100.48 (9) | C1—N4—H6 | 120.0 |
Se1—O3—H8 | 111.7 | C1—N4—H7 | 120.0 |
C2—N1—H1 | 120.0 | H6—N4—H7 | 120.0 |
C2—N1—H2 | 120.0 | N3—C1—N4 | 120.6 (2) |
H1—N1—H2 | 120.0 | N3—C1—N2 | 122.58 (19) |
C1—N2—C2 | 124.68 (17) | N4—C1—N2 | 116.81 (19) |
C1—N2—H3 | 117.7 | O4—C2—N1 | 123.2 (2) |
C2—N2—H3 | 117.7 | O4—C2—N2 | 121.83 (19) |
C1—N3—H4 | 120.0 | N1—C2—N2 | 114.98 (18) |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H8···O2i | 0.98 | 1.71 | 2.685 (3) | 173 |
N1—H1···O1ii | 0.86 | 2.15 | 2.990 (3) | 167 |
N1—H2···O2 | 0.86 | 2.06 | 2.903 (3) | 165 |
N2—H3···O1 | 0.86 | 1.99 | 2.824 (2) | 163 |
N3—H4···O2iii | 0.86 | 1.98 | 2.826 (2) | 169 |
N3—H5···O4 | 0.86 | 2.02 | 2.646 (3) | 129 |
N3—H5···O3iv | 0.86 | 2.48 | 3.132 (2) | 133 |
N4—H6···O3iii | 0.86 | 2.53 | 3.372 (3) | 165 |
N4—H7···O4v | 0.86 | 2.23 | 2.774 (2) | 122 |
N4—H7···O1 | 0.86 | 2.48 | 3.200 (3) | 142 |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x−1, y, z; (iii) x, y+1, z−1; (iv) x−1, y+1, z−1; (v) x+1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C2H7N4O+·HSeO3− |
Mr | 231.08 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 293 |
a, b, c (Å) | 6.7643 (4), 7.9045 (5), 8.2612 (5) |
α, β, γ (°) | 63.021 (1), 81.414 (1), 72.200 (1) |
V (Å3) | 374.77 (4) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 4.99 |
Crystal size (mm) | 0.45 × 0.35 × 0.30 |
Data collection | |
Diffractometer | Bruker SMART1000 CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 1999) |
Tmin, Tmax | 0.143, 0.224 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3843, 2591, 2259 |
Rint | 0.016 |
(sin θ/λ)max (Å−1) | 0.756 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.031, 0.078, 1.01 |
No. of reflections | 2591 |
No. of parameters | 100 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 1.00, −0.66 |
Computer programs: SMART (Bruker, 1999), SAINT (Bruker, 1999), SAINT, SHELXS97 (Sheldrick, 1997), SHELXL97, ORTEP-3 (Farrugia, 1997) and ATOMS (Shape Software, 1999).
Se1—O1 | 1.6523 (15) | N2—C1 | 1.359 (3) |
Se1—O2 | 1.6807 (16) | N2—C2 | 1.396 (3) |
Se1—O3 | 1.7626 (17) | N3—C1 | 1.308 (3) |
O4—C2 | 1.227 (3) | N4—C1 | 1.323 (3) |
N1—C2 | 1.328 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H8···O2i | 0.98 | 1.71 | 2.685 (3) | 173 |
N1—H1···O1ii | 0.86 | 2.15 | 2.990 (3) | 167 |
N1—H2···O2 | 0.86 | 2.06 | 2.903 (3) | 165 |
N2—H3···O1 | 0.86 | 1.99 | 2.824 (2) | 163 |
N3—H4···O2iii | 0.86 | 1.98 | 2.826 (2) | 169 |
N3—H5···O4 | 0.86 | 2.02 | 2.646 (3) | 129 |
N3—H5···O3iv | 0.86 | 2.48 | 3.132 (2) | 133 |
N4—H6···O3iii | 0.86 | 2.53 | 3.372 (3) | 165 |
N4—H7···O4v | 0.86 | 2.23 | 2.774 (2) | 122 |
N4—H7···O1 | 0.86 | 2.48 | 3.200 (3) | 142 |
Symmetry codes: (i) −x+1, −y, −z+1; (ii) x−1, y, z; (iii) x, y+1, z−1; (iv) x−1, y+1, z−1; (v) x+1, y, z. |
The title compound, (C2H7N4O)(HSeO3), (I) (Fig. 1), contains a hydrogen-bonded network of (C2H7N4O)+ (1-carbamoylguanidinium or guanylurea) cations and hydrogenselenite anions. It complements simple salt-like guanylurea compounds, including (C2H7N4O)(ClO4) (Begley et al., 1985), (C2H7N4O)(H2PO4) (Zaman & Darlow, 1986), (C2H7N4O)Cl·0.5H2O (Scoponi et al., 1991) and (C2H7N4O)(CH4PO3)·H2O (Brauer & Kottsieper, 2003)
In (I), the (C2H7N4O)+ cation has normal geometrical parameters (Begley et al., 1985), with dav(N—C) = 1.343 (3) Å, indicating significant delocalization of electrons over the non-H-atom skeleton (Scopoini et al., 1991) and is almost planar (for the non-H atoms, the root-mean-square deviation from the best least-squares plane = 0.031 Å). A non-linear (θ = 128.8°) intramolecular N3—H5···O4 hydrogen bond is present, which is typical for (C2H7N4O)+ (Bremner & Harrison, 2002). The (HSeO3)− hydrogenselenite group shows its standard (Verma, 1999) pyramidal geometry [dav(Se—O) = 1.699 (2) Å and θav(O—Se—O) = 102.2 (1)°], with the protonated Se–O3 vertex showing its expected lengthening relative to the other Se—O bonds.
The component species in (I) interact by means of a network of N—H···O and O—H···O hydrogen bonds (see Table 2 for symmetry codes). The guanylurea cations form hydrogen-bonded chains (via N4—H7···O4v bonds) crosslinked by the hydrogenselenite groups to form hydrogen-bonded layers (Fig. 2) in the (011) plane. There are various intermolecular hydrogen-bonding motifs including N—H···OS, and bifurcated N—H···(OS,OS) and N—H···(OS,OG) (S = selenite, G = guanylurea) bonds. Based on the H···O separations, these N—H···O bonds vary in strength from fairly strong (1.98 Å) to very weak (2.53 Å). Atoms O1 and O2 accept three hydrogen bonds each, and atoms O3 and O4 accept two each.
The strong, short, inter-selenite O3—H8···O2i hydrogen bonds help to fuse the layers into double sheets (Fig. 3); when considered in isolation, pairs of (HSeO3)− units form unusual, inversion-symmetry generated, dimers by way of two such bonds (Fig. 3). Pseudo-π–π-stacking interactions between adjacent guanylurea moieties [d(N2···C4i) = 3.295 (3) Å and d(N3···N1i) = 3.437 (3) Å] may also provide some coherence between the layers. The double sheets stack normal to (011), with bonding between the double sheets controlled by van der Waals forces.