Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270107054212/sq3109sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270107054212/sq3109Isup2.hkl | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270107054212/sq3109IIsup3.hkl | |
Portable Document Format (PDF) file https://doi.org/10.1107/S0108270107054212/sq3109sup3.pdf |
CCDC reference: 677079
For related literature, see: Ang et al. (2002); Bernstein et al. (1995); Christe et al. (1996); Etter et al. (1990); Gilardi & Butcher (1998); Gilardi et al. (1997); Pinkerton & Ritchie (2003); Trammell et al. (1996).
Compound (I) was obtained as a by-product in the preparation of a certain dinitramide salt. A mixture of trimethyltelluronium chloride (1.11 mmol) and [Ag(py)2][N3O4] (1.22 mmol) was dissolved in water (15 ml) and stirred at ambient temperature for 1 h. The resulting precipitate (AgCl) was removed by filtration and all volatile materials of the remaining solution removed in vacuo. Colourless crystals suitable for single-crystal X-ray diffraction were obtained by slow evaporation of a solution in acetone. The presence of lithium in the structure arises from impurities in the starting material [Me3Te]Cl that result from its preparation via the reaction of TeCl4 with MeLi, and was proved by 7Li NMR spectroscopy (δ -0.99 p.p.m.).
Compound (II) was obtained as a by-product in the attempted preparation of an organodinitramide with the help of [Ag(py)2][N3O4] as a dinitramide transfer reagent (Ang et al., 2002). Single crystals were grown by slow evaporation of a dichloromethane solution.
Water H atoms of (I) were located in a difference Fourier map and refined freely with isotropic displacement parameters. The highest peak and deepest hole in the final difference map are located 0.57 Å from N1 and 0.73 Å from N2, respectively. H atoms in (II) were placed in idealized positions and allowed to ride on their respective parent atoms, with Carom—H = 0.95 and Narom—H = 0.88 Å, and with Uiso(H) = 1.2Ueq(carrier atom). The highest peak and deepest hole in the final difference map are located 0.72 Å from H2 and 1.24 Å from C1, respectively.
For both compounds, data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SIR97 (Altomare et al., 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: DIAMOND (Brandenburg, 1996); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).
[Li(N3O4)(H2O)2] | F(000) = 304 |
Mr = 148.99 | Dx = 1.780 (1) Mg m−3 |
Monoclinic, C2/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -C 2yc | Cell parameters from 448 reflections |
a = 12.574 (5) Å | θ = 3.8–30.0° |
b = 7.679 (5) Å | µ = 0.19 mm−1 |
c = 6.321 (5) Å | T = 200 K |
β = 114.351 (5)° | Platelet, colourless |
V = 556.0 (6) Å3 | 0.13 × 0.10 × 0.02 mm |
Z = 4 |
Oxford Xcalibur3 CCD area-detector diffractometer | 575 independent reflections |
Radiation source: fine-focus sealed tube | 312 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.038 |
Detector resolution: 15.9809 pixels mm-1 | θmax = 26.5°, θmin = 4.2° |
ω scans | h = −12→15 |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006) (empirical (using intensity measurements) absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm) | k = −8→9 |
Tmin = 0.977, Tmax = 0.999 | l = −7→6 |
1464 measured reflections |
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)] = 0.033 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.069 | All H-atom parameters refined |
S = 1.00 | w = 1/[σ2(Fo2) + (0.0332P)2] where P = (Fo2 + 2Fc2)/3 |
575 reflections | (Δ/σ)max < 0.001 |
55 parameters | Δρmax = 0.20 e Å−3 |
2 restraints | Δρmin = −0.23 e Å−3 |
[Li(N3O4)(H2O)2] | V = 556.0 (6) Å3 |
Mr = 148.99 | Z = 4 |
Monoclinic, C2/c | Mo Kα radiation |
a = 12.574 (5) Å | µ = 0.19 mm−1 |
b = 7.679 (5) Å | T = 200 K |
c = 6.321 (5) Å | 0.13 × 0.10 × 0.02 mm |
β = 114.351 (5)° |
Oxford Xcalibur3 CCD area-detector diffractometer | 575 independent reflections |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006) (empirical (using intensity measurements) absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm) | 312 reflections with I > 2σ(I) |
Tmin = 0.977, Tmax = 0.999 | Rint = 0.038 |
1464 measured reflections |
R[F2 > 2σ(F2)] = 0.033 | 2 restraints |
wR(F2) = 0.069 | All H-atom parameters refined |
S = 1.00 | Δρmax = 0.20 e Å−3 |
575 reflections | Δρmin = −0.23 e Å−3 |
55 parameters |
Refinement. Details of H atom refinement: The water H atoms were located in a difference Fourier map, and freely refined with isotropic displacement parameters The highest peak and deepest hole in the final difference map were located 0.57 Å from N1 and 0.73 Å from N2, respectively. |
x | y | z | Uiso*/Ueq | ||
Li1 | 0.0000 | 0.4303 (7) | 0.7500 | 0.0582 (17) | |
N1 | 0.0000 | −0.0305 (3) | 0.7500 | 0.0248 (6) | |
N2 | 0.09544 (13) | 0.0627 (2) | 0.7629 (3) | 0.0257 (4) | |
O1 | 0.17636 (10) | −0.03601 (16) | 0.7782 (2) | 0.0345 (4) | |
O2 | 0.10364 (10) | 0.22187 (16) | 0.7560 (2) | 0.0344 (4) | |
O3 | 0.10269 (15) | 0.5906 (2) | 0.6806 (3) | 0.0417 (5) | |
H1 | 0.175 (2) | 0.557 (3) | 0.703 (4) | 0.059 (8)* | |
H2 | 0.1093 (19) | 0.686 (4) | 0.730 (4) | 0.066 (10)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
Li1 | 0.050 (3) | 0.025 (3) | 0.110 (5) | 0.000 | 0.043 (3) | 0.000 |
N1 | 0.0250 (12) | 0.0167 (12) | 0.0344 (16) | 0.000 | 0.0138 (12) | 0.000 |
N2 | 0.0288 (9) | 0.0245 (9) | 0.0238 (11) | 0.0020 (8) | 0.0107 (7) | −0.0005 (8) |
O1 | 0.0311 (8) | 0.0295 (8) | 0.0443 (11) | 0.0098 (6) | 0.0169 (7) | 0.0013 (6) |
O2 | 0.0365 (9) | 0.0187 (7) | 0.0504 (10) | −0.0028 (6) | 0.0202 (7) | −0.0012 (7) |
O3 | 0.0374 (10) | 0.0220 (9) | 0.0663 (13) | −0.0009 (7) | 0.0220 (9) | −0.0002 (9) |
Li1—O3i | 1.960 (4) | N1—N2 | 1.3707 (18) |
Li1—O3 | 1.960 (4) | N1—N2i | 1.3707 (18) |
Li1—O2i | 2.054 (4) | N2—O2 | 1.229 (2) |
Li1—O2 | 2.054 (4) | N2—O1 | 1.2403 (18) |
Li1—O3ii | 2.490 (3) | O3—Li1iii | 2.490 (3) |
Li1—O3iii | 2.490 (3) | O3—H1 | 0.89 (3) |
Li1—Li1iv | 3.337 (4) | O3—H2 | 0.79 (3) |
Li1—Li1iii | 3.337 (4) | ||
O3i—Li1—O3 | 102.2 (3) | O3iii—Li1—Li1iv | 148.57 (14) |
O3i—Li1—O2i | 91.26 (8) | O3i—Li1—Li1iii | 105.5 (2) |
O3—Li1—O2i | 163.03 (17) | O3—Li1—Li1iii | 47.87 (10) |
O3i—Li1—O2 | 163.03 (17) | O2i—Li1—Li1iii | 118.69 (14) |
O3—Li1—O2 | 91.26 (8) | O2—Li1—Li1iii | 91.13 (10) |
O2i—Li1—O2 | 77.6 (2) | O3ii—Li1—Li1iii | 148.57 (15) |
O3i—Li1—O3ii | 83.59 (10) | O3iii—Li1—Li1iii | 35.72 (5) |
O3—Li1—O3ii | 101.10 (11) | Li1iv—Li1—Li1iii | 142.6 (3) |
O2i—Li1—O3ii | 90.52 (12) | N2—N1—N2i | 117.0 (2) |
O2—Li1—O3ii | 83.71 (11) | O2—N2—O1 | 122.19 (16) |
O3i—Li1—O3iii | 101.10 (11) | O2—N2—N1 | 126.98 (16) |
O3—Li1—O3iii | 83.59 (10) | O1—N2—N1 | 110.81 (15) |
O2i—Li1—O3iii | 83.71 (11) | N2—O2—Li1 | 135.54 (16) |
O2—Li1—O3iii | 90.52 (12) | Li1—O3—Li1iii | 96.41 (10) |
O3ii—Li1—O3iii | 172.6 (3) | Li1—O3—H1 | 120.0 (14) |
O3i—Li1—Li1iv | 47.87 (10) | Li1iii—O3—H1 | 101.0 (16) |
O3—Li1—Li1iv | 105.5 (2) | Li1—O3—H2 | 117.7 (18) |
O2i—Li1—Li1iv | 91.13 (10) | Li1iii—O3—H2 | 114.7 (19) |
O2—Li1—Li1iv | 118.69 (14) | H1—O3—H2 | 106 (2) |
O3ii—Li1—Li1iv | 35.72 (5) | ||
N2i—N1—N2—O2 | −2.74 (14) | Li1iv—Li1—O2—N2 | 81.6 (3) |
N2i—N1—N2—O1 | 178.70 (16) | Li1iii—Li1—O2—N2 | −122.0 (2) |
O1—N2—O2—Li1 | −175.83 (13) | O3i—Li1—O3—Li1iii | −100.02 (11) |
N1—N2—O2—Li1 | 5.8 (3) | O2i—Li1—O3—Li1iii | 41.8 (5) |
O3i—Li1—O2—N2 | 47.3 (6) | O2—Li1—O3—Li1iii | 90.39 (12) |
O3—Li1—O2—N2 | −169.88 (19) | O3ii—Li1—O3—Li1iii | 174.2 (2) |
O2i—Li1—O2—N2 | −2.84 (15) | O3iii—Li1—O3—Li1iii | 0.0 |
O3ii—Li1—O2—N2 | 89.1 (2) | Li1iv—Li1—O3—Li1iii | −149.3 (2) |
O3iii—Li1—O2—N2 | −86.3 (2) |
Symmetry codes: (i) −x, y, −z+3/2; (ii) x, −y+1, z+1/2; (iii) −x, −y+1, −z+1; (iv) −x, −y+1, −z+2. |
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H1···O1v | 0.89 (3) | 1.96 (3) | 2.852 (2) | 173 (2) |
Symmetry code: (v) −x+1/2, y+1/2, −z+3/2. |
C5H6N+·N3O4− | F(000) = 384 |
Mr = 186.13 | Dx = 1.585 (1) Mg m−3 |
Monoclinic, P21/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yn | Cell parameters from 868 reflections |
a = 3.7009 (2) Å | θ = 4.0–30.0° |
b = 14.4548 (7) Å | µ = 0.14 mm−1 |
c = 14.6214 (8) Å | T = 200 K |
β = 94.281 (6)° | Needle, colourless |
V = 780.00 (7) Å3 | 0.21 × 0.10 × 0.06 mm |
Z = 4 |
Oxford Xcalibur3 CCD area-detector diffractometer | 1537 independent reflections |
Radiation source: fine-focus sealed tube | 881 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.047 |
Detector resolution: 15.9809 pixels mm-1 | θmax = 26.0°, θmin = 4.0° |
ω scans | h = −4→2 |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006) (empirical (using intensity measurements) absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm) | k = −17→17 |
Tmin = 0.982, Tmax = 0.995 | l = −17→17 |
3991 measured reflections |
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)] = 0.035 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.077 | H-atom parameters constrained |
S = 0.98 | w = 1/[σ2(Fo2) + (0.032P)2] where P = (Fo2 + 2Fc2)/3 |
1537 reflections | (Δ/σ)max < 0.001 |
118 parameters | Δρmax = 0.12 e Å−3 |
0 restraints | Δρmin = −0.17 e Å−3 |
C5H6N+·N3O4− | V = 780.00 (7) Å3 |
Mr = 186.13 | Z = 4 |
Monoclinic, P21/n | Mo Kα radiation |
a = 3.7009 (2) Å | µ = 0.14 mm−1 |
b = 14.4548 (7) Å | T = 200 K |
c = 14.6214 (8) Å | 0.21 × 0.10 × 0.06 mm |
β = 94.281 (6)° |
Oxford Xcalibur3 CCD area-detector diffractometer | 1537 independent reflections |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2006) (empirical (using intensity measurements) absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm) | 881 reflections with I > 2σ(I) |
Tmin = 0.982, Tmax = 0.995 | Rint = 0.047 |
3991 measured reflections |
R[F2 > 2σ(F2)] = 0.035 | 0 restraints |
wR(F2) = 0.077 | H-atom parameters constrained |
S = 0.98 | Δρmax = 0.12 e Å−3 |
1537 reflections | Δρmin = −0.17 e Å−3 |
118 parameters |
Refinement. Details of H atom refinement: H atoms were placed in idealized positions and allowed to ride on their respective parent atoms, with Carom–H = 0.95 and Narom–H = 0.88 Å, and with Uiso(H) = kUeq(carrier atom), where k = 1.2 for CH. The highest peak and deepest hole in the final difference map were located 0.72 Å from H2 and 1.24 Å from C1, respectively. |
x | y | z | Uiso*/Ueq | ||
N1 | 0.6253 (5) | 0.43555 (11) | 0.69643 (10) | 0.0399 (5) | |
N2 | 0.5614 (5) | 0.52747 (14) | 0.67356 (12) | 0.0447 (5) | |
O1 | 0.3597 (5) | 0.53381 (10) | 0.60286 (10) | 0.0626 (5) | |
O2 | 0.6900 (5) | 0.59413 (10) | 0.71511 (10) | 0.0680 (6) | |
N3 | 0.8279 (5) | 0.41827 (13) | 0.77710 (11) | 0.0421 (5) | |
O3 | 0.8931 (4) | 0.33517 (10) | 0.78669 (9) | 0.0567 (5) | |
O4 | 0.9302 (5) | 0.47668 (11) | 0.83292 (11) | 0.0703 (5) | |
N4 | 0.2594 (4) | 0.29446 (13) | 0.59717 (12) | 0.0409 (5) | |
H4A | 0.3636 | 0.3364 | 0.6340 | 0.049* | |
C1 | 0.1227 (6) | 0.32031 (14) | 0.51406 (15) | 0.0415 (6) | |
H1 | 0.1375 | 0.3830 | 0.4952 | 0.050* | |
C2 | −0.0385 (5) | 0.25588 (15) | 0.45651 (14) | 0.0424 (6) | |
H2 | −0.1353 | 0.2731 | 0.3969 | 0.051* | |
C3 | −0.0594 (6) | 0.16640 (15) | 0.48540 (16) | 0.0433 (6) | |
H3 | −0.1722 | 0.1211 | 0.4458 | 0.052* | |
C4 | 0.0824 (6) | 0.14153 (14) | 0.57159 (15) | 0.0456 (6) | |
H4 | 0.0676 | 0.0795 | 0.5923 | 0.055* | |
C5 | 0.2437 (5) | 0.20785 (16) | 0.62622 (14) | 0.0436 (6) | |
H5 | 0.3460 | 0.1920 | 0.6857 | 0.052* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0486 (12) | 0.0329 (10) | 0.0366 (11) | −0.0033 (8) | −0.0085 (10) | 0.0032 (8) |
N2 | 0.0478 (13) | 0.0416 (12) | 0.0445 (12) | −0.0026 (11) | 0.0028 (10) | 0.0038 (11) |
O1 | 0.0666 (12) | 0.0607 (11) | 0.0572 (11) | 0.0037 (9) | −0.0175 (10) | 0.0120 (9) |
O2 | 0.0967 (15) | 0.0389 (10) | 0.0672 (12) | −0.0138 (9) | −0.0022 (11) | −0.0084 (9) |
N3 | 0.0381 (12) | 0.0477 (13) | 0.0403 (12) | 0.0005 (10) | 0.0009 (10) | −0.0016 (10) |
O3 | 0.0748 (13) | 0.0407 (10) | 0.0531 (10) | 0.0115 (9) | −0.0045 (9) | 0.0075 (8) |
O4 | 0.0804 (13) | 0.0605 (10) | 0.0642 (11) | 0.0054 (10) | −0.0339 (10) | −0.0222 (9) |
N4 | 0.0385 (12) | 0.0418 (12) | 0.0418 (12) | −0.0017 (9) | −0.0001 (10) | −0.0111 (9) |
C1 | 0.0425 (14) | 0.0379 (13) | 0.0444 (14) | −0.0018 (11) | 0.0055 (12) | 0.0066 (12) |
C2 | 0.0409 (15) | 0.0528 (15) | 0.0326 (13) | 0.0039 (12) | −0.0037 (11) | −0.0003 (12) |
C3 | 0.0350 (14) | 0.0457 (15) | 0.0490 (15) | −0.0030 (11) | 0.0015 (12) | −0.0116 (12) |
C4 | 0.0447 (14) | 0.0354 (14) | 0.0564 (16) | 0.0002 (11) | 0.0033 (13) | 0.0040 (12) |
C5 | 0.0383 (15) | 0.0533 (15) | 0.0386 (13) | 0.0070 (12) | −0.0012 (12) | 0.0028 (13) |
N1—N3 | 1.372 (2) | N4—H4A | 0.8800 |
N1—N2 | 1.386 (2) | C1—C2 | 1.363 (3) |
N2—O2 | 1.2169 (19) | C1—H1 | 0.9500 |
N2—O1 | 1.2326 (19) | C2—C3 | 1.365 (3) |
N2—N1 | 1.386 (2) | C2—H2 | 0.9500 |
N3—O4 | 1.2150 (19) | C3—C4 | 1.376 (3) |
N3—O3 | 1.2312 (18) | C3—H3 | 0.9500 |
N3—N1 | 1.372 (2) | C4—C5 | 1.357 (3) |
N4—C5 | 1.325 (2) | C4—H4 | 0.9500 |
N4—C1 | 1.334 (2) | C5—H5 | 0.9500 |
N3—N1—N2 | 117.01 (16) | N4—C1—H1 | 120.3 |
O2—N2—O1 | 123.34 (19) | C2—C1—H1 | 120.3 |
O2—N2—N1 | 125.82 (17) | C1—C2—C3 | 119.3 (2) |
O1—N2—N1 | 110.82 (18) | C1—C2—H2 | 120.4 |
O2—N2—N1 | 125.82 (17) | C3—C2—H2 | 120.4 |
O1—N2—N1 | 110.82 (18) | C2—C3—C4 | 120.31 (19) |
O4—N3—O3 | 123.56 (18) | C2—C3—H3 | 119.8 |
O4—N3—N1 | 125.01 (18) | C4—C3—H3 | 119.8 |
O3—N3—N1 | 111.43 (16) | C5—C4—C3 | 118.4 (2) |
O4—N3—N1 | 125.01 (18) | C5—C4—H4 | 120.8 |
O3—N3—N1 | 111.43 (16) | C3—C4—H4 | 120.8 |
C5—N4—C1 | 122.27 (17) | N4—C5—C4 | 120.4 (2) |
C5—N4—H4A | 118.9 | N4—C5—H5 | 119.8 |
C1—N4—H4A | 118.9 | C4—C5—H5 | 119.8 |
N4—C1—C2 | 119.32 (19) | ||
N3—N1—N2—O2 | 5.6 (3) | N4—C1—C2—C3 | 0.5 (3) |
N3—N1—N2—O1 | −175.99 (17) | C1—C2—C3—C4 | −0.3 (3) |
N2—N1—N3—O4 | 6.1 (3) | C2—C3—C4—C5 | −0.4 (3) |
N2—N1—N3—O3 | −174.32 (17) | C1—N4—C5—C4 | −0.5 (3) |
C5—N4—C1—C2 | −0.1 (3) | C3—C4—C5—N4 | 0.8 (3) |
Experimental details
(I) | (II) | |
Crystal data | ||
Chemical formula | [Li(N3O4)(H2O)2] | C5H6N+·N3O4− |
Mr | 148.99 | 186.13 |
Crystal system, space group | Monoclinic, C2/c | Monoclinic, P21/n |
Temperature (K) | 200 | 200 |
a, b, c (Å) | 12.574 (5), 7.679 (5), 6.321 (5) | 3.7009 (2), 14.4548 (7), 14.6214 (8) |
β (°) | 114.351 (5) | 94.281 (6) |
V (Å3) | 556.0 (6) | 780.00 (7) |
Z | 4 | 4 |
Radiation type | Mo Kα | Mo Kα |
µ (mm−1) | 0.19 | 0.14 |
Crystal size (mm) | 0.13 × 0.10 × 0.02 | 0.21 × 0.10 × 0.06 |
Data collection | ||
Diffractometer | Oxford Xcalibur3 CCD area-detector diffractometer | Oxford Xcalibur3 CCD area-detector diffractometer |
Absorption correction | Multi-scan (CrysAlis RED; Oxford Diffraction, 2006) (empirical (using intensity measurements) absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm) | Multi-scan (CrysAlis RED; Oxford Diffraction, 2006) (empirical (using intensity measurements) absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm) |
Tmin, Tmax | 0.977, 0.999 | 0.982, 0.995 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 1464, 575, 312 | 3991, 1537, 881 |
Rint | 0.038 | 0.047 |
(sin θ/λ)max (Å−1) | 0.628 | 0.617 |
Refinement | ||
R[F2 > 2σ(F2)], wR(F2), S | 0.033, 0.069, 1.00 | 0.035, 0.077, 0.98 |
No. of reflections | 575 | 1537 |
No. of parameters | 55 | 118 |
No. of restraints | 2 | 0 |
H-atom treatment | All H-atom parameters refined | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.20, −0.23 | 0.12, −0.17 |
Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SIR97 (Altomare et al., 1999), SHELXL97 (Sheldrick, 1997), DIAMOND (Brandenburg, 1996).
D—H···A | D—H | H···A | D···A | D—H···A |
O3—H1···O1i | 0.89 (3) | 1.96 (3) | 2.852 (2) | 173 (2) |
Symmetry code: (i) −x+1/2, y+1/2, −z+3/2. |
D—H···A | D—H | H···A | D···A | D—H···A |
N4—H4A···N1 | 0.88 | 1.92 | 2.794 (2) | 170.5 |
Subscribe to Acta Crystallographica Section C: Structural Chemistry
The full text of this article is available to subscribers to the journal.
- Information on subscribing
- Sample issue
- Purchase subscription
- Reduced-price subscriptions
- If you have already subscribed, you may need to register
The potential coordination modes (Trammell et al., 1996) of dinitramide include monodentate coordination to the central N atom of the dinitramide skeleton, monodentate coordination to one O atom of the nitro groups, and bidentate coordination to two O atoms of the terminal nitro groups. We report here the molecular structures of the dinitramide salts (I) and (II), and compare (I) with its anhydrous homologue and (II) with ammonium dinitramide in terms of cation–anion contacts.
Compound (I) exhibits a distorted octahedral Li+ cation with a chelate-type coordination by two O atoms of the dinitramide anion and four additional water molecules (Fig. 1). Analogous to what was observed in the anhydrous compound, Li(N3O4) (Gilardi et al., 1997), the Li+ atom is located on a twofold rotation axis which also bisects the dinitramide anion. To the best of our knowledge, these two cases present the only examples of imposed C2 symmetry in a dinitramide. In all other cases, the dinitramide anion has C1 symmetry, except for 3,3-dinitroazetidinium, where a crystallographically imposed mirror plane passes through the dinitramide anion (Gilardi & Butcher, 1998).
The Li—O distances to the water molecules are 1.960 (4) (Li1–O3) and 2.490 (3) Å [Li1–O3ii; symmetry code: (ii) -x, 1 - y, 1 - z], whereas the distance between the Li+ atom and the O atom of the dinitramide moiety is 2.054 (4) Å. In Li(N3O4) (Gilardi et al., 1997) the five Li—O distances range from 2.028 (5) to 2.200 (2) Å and are exclusively contacts to O atoms of the dinitramide moiety. Thus, the entire packing in Li(N3O4) is based on Li—O(dinitramide) bonding. By contrast, the presence of the coordinated water in (I) allows for the formation of an approximately linear Owater—H···Odinitramide hydrogen bond which generates by translation a C(5) chain (Etter et al., 1990; Bernstein et al., 1995) running along the [100] direction (Fig. 1).
The dinitramide moiety in (I) is nearly planar, with a twist angle of 2.0°. This is a measure of the degree by which the nitro group has rotated out of the NNN plane (Pinkerton & Ritchie, 2003; Gilardi, et al. 1997) and is significantly smaller than the twist angle of 15.8° in Li(N3O4) (Gilardi et al., 1997). The dinitramide moiety has a bend angle of 1.3°, representing the pyramidalization of the nitro N atoms (expected values are 0° for ideal sp2 and 54.8° for ideal sp3 conformations), and this value is slightly smaller than the bend angle of 4.6° found in Li(N3O4).
The O···O chelate distance in (I) [2.576 (2) Å] is comparable with that reported for Li(N3O4) [2.593 Å], while the pseudotorsion angle between the two closest N—O bonds in different nitro groups in the molecule is smaller in (I) [4.4°, versus 29.6° in Li(N3O4)].
In contrast with the dinitramide coordination in (I), compound (II) exhibits an intermolecular secondary contact to the central N atom of the dinitramide moiety via an N—H···N hydrogen bond (Fig. 2). The dinitramide anion has C1 symmetry, with N—N and N—O distances comparable with those in compound (I) and other dinitramide anions (Gilardi et al., 1997; Christe et al., 1996).
The twist and bend angles of the dinitramide moiety tend, as also observed in (I), to a relatively planar conformation (twist angles 4.8 and 5.9°; bend angles 1.5 and 0.4°) and are significantly different from those in ammonium dinitramide (twist angles 25.6 and 20.8°; bend angles 5.1 and 5.3°; Gilardi et al., 1997).
The O···O distance in (II) is slightly smaller than that in the ammonium salt [2.532 (4) versus 2.591 Å, respectively] and the pseudotorsion angle is considerably smaller [9.6 versus 37.9°, respectively].
Atom N4 in the cation of (II) acts as hydrogen-bond donor to atom N1 in the anion, giving rise to an approximately linear N—H···N interaction. Since no further hydrogen bonds are present, the structure of (II) consists of isolated cation–anion pairs with no significant interactions between them. This is in contrast with ammonium dinitramide, where extensive hydrogen bonding involving all four ammonium H atoms furnishes a multi-dimensional hydrogen-bond architecture (Gilardi et al., 1997). The hydrogen bonds are directed tetrahedrally involving exclusively the O atoms of the dinitramide moiety as hydrogen-bond acceptors, with H···O distances in the range 2.153–2.230 Å.
The packing motif in (II) consists of layers lying parallel to the bc plane with different orientations of the cation–anion pairs and a distance of 3.7 Å between those layers along the a axis (Fig. 3).