Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536801010054/ob6050sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536801010054/ob6050Isup2.hkl |
CCDC reference: 170887
Key indicators
- Single-crystal X-ray study
- T = 293 K
- Mean (C-C) = 0.003 Å
- R factor = 0.036
- wR factor = 0.107
- Data-to-parameter ratio = 11.8
checkCIF results
No syntax errors found ADDSYM reports no extra symmetry
The title compound was crystallized from aqueous solution of DL-aspartic acid and sulfuric acid in a stoichiometric ratio of 2:1.
All H atoms were fixed by geometric restraints using HFIX and were allowed to ride on the preceding atom.
Data collection: CAD-4 Software (Enraf-Nonius, 1989); cell refinement: CAD-4 Software; data reduction: CAD-4 Software; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 1999); software used to prepare material for publication: SHELXL97.
2C4H8NO4+·SO42− | F(000) = 760 |
Mr = 364.29 | Dx = 1.683 Mg m−3 Dm = 1.674 Mg m−3 Dm measured by flotation in a mixture of bromoform and xylene |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71069 Å |
a = 16.774 (4) Å | Cell parameters from 25 reflections |
b = 5.9697 (9) Å | θ = 8.9–14.5° |
c = 14.5276 (18) Å | µ = 0.30 mm−1 |
β = 98.66 (2)° | T = 293 K |
V = 1438.1 (4) Å3 | Needles, colorless |
Z = 4 | 0.5 × 0.4 × 0.2 mm |
Enraf-Nonius sealed tube diffractometer | 2113 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.014 |
Graphite monochromator | θmax = 25.0°, θmin = 2.5° |
ω–2θ scans | h = −19→19 |
Absorption correction: ψ scan (North et al., 1968) | k = 0→7 |
Tmin = 0.868, Tmax = 0.943 | l = 0→17 |
2616 measured reflections | 25 standard reflections every 3 reflections |
2502 independent reflections | intensity decay: none |
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)] = 0.036 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.107 | H-atom parameters constrained |
S = 0.81 | w = 1/[σ2(Fo2) + (0.0827P)2 + 1.6327P] where P = (Fo2 + 2Fc2)/3 |
2502 reflections | (Δ/σ)max = 0.001 |
212 parameters | Δρmax = 0.38 e Å−3 |
0 restraints | Δρmin = −0.38 e Å−3 |
2C4H8NO4+·SO42− | V = 1438.1 (4) Å3 |
Mr = 364.29 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 16.774 (4) Å | µ = 0.30 mm−1 |
b = 5.9697 (9) Å | T = 293 K |
c = 14.5276 (18) Å | 0.5 × 0.4 × 0.2 mm |
β = 98.66 (2)° |
Enraf-Nonius sealed tube diffractometer | 2113 reflections with I > 2σ(I) |
Absorption correction: ψ scan (North et al., 1968) | Rint = 0.014 |
Tmin = 0.868, Tmax = 0.943 | 25 standard reflections every 3 reflections |
2616 measured reflections | intensity decay: none |
2502 independent reflections |
R[F2 > 2σ(F2)] = 0.036 | 0 restraints |
wR(F2) = 0.107 | H-atom parameters constrained |
S = 0.81 | Δρmax = 0.38 e Å−3 |
2502 reflections | Δρmin = −0.38 e Å−3 |
212 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 | ||
S | 0.73852 (3) | 0.11327 (8) | 0.26890 (3) | 0.02349 (17) | |
O1 | 0.71791 (9) | 0.1535 (3) | 0.36215 (10) | 0.0353 (4) | |
O2 | 0.72809 (11) | 0.3215 (3) | 0.21513 (11) | 0.0459 (4) | |
O3 | 0.68580 (9) | −0.0628 (3) | 0.22228 (10) | 0.0328 (4) | |
O4 | 0.82218 (9) | 0.0354 (3) | 0.27733 (13) | 0.0476 (5) | |
O1A | 0.98758 (9) | 0.4639 (3) | 0.21248 (12) | 0.0412 (4) | |
O1B | 1.04825 (9) | 0.6711 (3) | 0.11540 (12) | 0.0475 (5) | |
H1B | 1.0898 | 0.6229 | 0.1460 | 0.071* | |
C11 | 0.98595 (12) | 0.6028 (4) | 0.15248 (15) | 0.0302 (5) | |
C12 | 0.90784 (11) | 0.7087 (4) | 0.10616 (14) | 0.0288 (4) | |
H12 | 0.8922 | 0.6331 | 0.0463 | 0.035* | |
N11 | 0.84489 (10) | 0.6584 (3) | 0.16526 (14) | 0.0360 (5) | |
H11A | 0.7982 | 0.7187 | 0.1397 | 0.054* | |
H11B | 0.8596 | 0.7157 | 0.2218 | 0.054* | |
H11C | 0.8392 | 0.5107 | 0.1696 | 0.054* | |
C13 | 0.91137 (13) | 0.9605 (4) | 0.08663 (15) | 0.0340 (5) | |
H13A | 0.9011 | 1.0427 | 0.1412 | 0.041* | |
H13B | 0.9651 | 0.9991 | 0.0750 | 0.041* | |
C14 | 0.85100 (12) | 1.0295 (4) | 0.00446 (15) | 0.0294 (5) | |
O1C | 0.83116 (10) | 0.9103 (3) | −0.06259 (12) | 0.0432 (4) | |
O1D | 0.82279 (10) | 1.2349 (3) | 0.01231 (11) | 0.0398 (4) | |
H1D | 0.7922 | 1.2675 | −0.0353 | 0.060* | |
O2A | 0.52138 (10) | 0.5126 (3) | 0.25354 (12) | 0.0492 (5) | |
O2B | 0.45700 (9) | 0.4946 (3) | 0.37783 (11) | 0.0410 (4) | |
H2B | 0.4164 | 0.4785 | 0.3392 | 0.061* | |
C21 | 0.51934 (13) | 0.5317 (3) | 0.33496 (14) | 0.0298 (5) | |
C22 | 0.59179 (12) | 0.6065 (3) | 0.40399 (14) | 0.0265 (4) | |
H22 | 0.6018 | 0.4964 | 0.4545 | 0.032* | |
N21 | 0.66305 (10) | 0.6158 (3) | 0.35483 (13) | 0.0312 (4) | |
H21A | 0.7060 | 0.6593 | 0.3944 | 0.047* | |
H21B | 0.6539 | 0.7130 | 0.3080 | 0.047* | |
H21C | 0.6720 | 0.4807 | 0.3327 | 0.047* | |
C23 | 0.57612 (12) | 0.8343 (4) | 0.44503 (15) | 0.0303 (5) | |
H23A | 0.5695 | 0.9450 | 0.3956 | 0.036* | |
H23B | 0.5262 | 0.8277 | 0.4710 | 0.036* | |
C24 | 0.64290 (12) | 0.9077 (4) | 0.51963 (14) | 0.0276 (4) | |
O2C | 0.70441 (9) | 0.8008 (3) | 0.54036 (10) | 0.0367 (4) | |
O2D | 0.62699 (10) | 1.0965 (3) | 0.55860 (13) | 0.0488 (5) | |
H2D | 0.6583 | 1.1135 | 0.6072 | 0.073* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S | 0.0146 (3) | 0.0262 (3) | 0.0281 (3) | −0.00044 (18) | −0.00200 (18) | 0.00032 (19) |
O1 | 0.0320 (8) | 0.0412 (9) | 0.0320 (8) | −0.0044 (7) | 0.0022 (6) | −0.0036 (7) |
O2 | 0.0594 (11) | 0.0364 (9) | 0.0379 (9) | −0.0061 (8) | −0.0059 (8) | 0.0080 (7) |
O3 | 0.0243 (8) | 0.0321 (8) | 0.0386 (8) | −0.0021 (6) | −0.0065 (6) | −0.0058 (6) |
O4 | 0.0149 (8) | 0.0656 (12) | 0.0600 (11) | 0.0047 (7) | −0.0016 (7) | −0.0144 (9) |
O1A | 0.0283 (8) | 0.0393 (9) | 0.0524 (10) | 0.0002 (7) | −0.0053 (7) | 0.0155 (8) |
O1B | 0.0202 (8) | 0.0658 (12) | 0.0564 (10) | 0.0056 (8) | 0.0049 (7) | 0.0179 (9) |
C11 | 0.0205 (10) | 0.0316 (11) | 0.0357 (11) | 0.0004 (8) | −0.0044 (8) | −0.0011 (9) |
C12 | 0.0181 (9) | 0.0322 (11) | 0.0335 (10) | −0.0024 (8) | −0.0042 (8) | −0.0002 (9) |
N11 | 0.0164 (8) | 0.0380 (11) | 0.0514 (11) | −0.0016 (7) | −0.0015 (8) | 0.0085 (9) |
C13 | 0.0264 (10) | 0.0325 (12) | 0.0404 (12) | −0.0037 (9) | −0.0043 (9) | 0.0032 (9) |
C14 | 0.0229 (10) | 0.0306 (11) | 0.0339 (11) | −0.0032 (8) | 0.0018 (8) | 0.0049 (9) |
O1C | 0.0426 (10) | 0.0412 (10) | 0.0414 (9) | 0.0004 (8) | −0.0079 (7) | −0.0035 (8) |
O1D | 0.0404 (9) | 0.0375 (9) | 0.0380 (8) | 0.0078 (7) | −0.0050 (7) | 0.0008 (7) |
O2A | 0.0439 (10) | 0.0662 (12) | 0.0348 (9) | −0.0095 (9) | −0.0029 (8) | −0.0100 (8) |
O2B | 0.0246 (8) | 0.0567 (11) | 0.0387 (8) | −0.0073 (8) | −0.0045 (6) | −0.0031 (8) |
C21 | 0.0292 (11) | 0.0232 (10) | 0.0342 (11) | 0.0001 (8) | −0.0040 (8) | −0.0015 (8) |
C22 | 0.0221 (10) | 0.0271 (11) | 0.0286 (10) | 0.0003 (8) | −0.0020 (8) | −0.0004 (8) |
N21 | 0.0251 (9) | 0.0310 (10) | 0.0371 (10) | 0.0024 (7) | 0.0033 (7) | −0.0065 (7) |
C23 | 0.0214 (10) | 0.0333 (12) | 0.0337 (11) | 0.0040 (8) | −0.0036 (8) | −0.0061 (9) |
C24 | 0.0207 (10) | 0.0335 (11) | 0.0279 (10) | −0.0022 (9) | 0.0016 (8) | −0.0016 (8) |
O2C | 0.0256 (8) | 0.0434 (9) | 0.0373 (8) | 0.0078 (7) | −0.0078 (6) | −0.0060 (7) |
O2D | 0.0349 (9) | 0.0530 (11) | 0.0529 (11) | 0.0136 (8) | −0.0116 (8) | −0.0287 (9) |
S—O2 | 1.4646 (17) | C14—O1D | 1.325 (3) |
S—O4 | 1.4658 (16) | O1D—H1D | 0.8200 |
S—O1 | 1.4673 (16) | O2A—C21 | 1.194 (3) |
S—O3 | 1.4713 (15) | O2B—C21 | 1.314 (3) |
O1A—C11 | 1.200 (3) | O2B—H2B | 0.8200 |
O1B—C11 | 1.311 (3) | C21—C22 | 1.522 (3) |
O1B—H1B | 0.8200 | C22—N21 | 1.483 (3) |
C11—C12 | 1.518 (3) | C22—C23 | 1.524 (3) |
C12—N11 | 1.488 (3) | C22—H22 | 0.9800 |
C12—C13 | 1.532 (3) | N21—H21A | 0.8900 |
C12—H12 | 0.9800 | N21—H21B | 0.8900 |
N11—H11A | 0.8900 | N21—H21C | 0.8900 |
N11—H11B | 0.8900 | C23—C24 | 1.502 (3) |
N11—H11C | 0.8900 | C23—H23A | 0.9700 |
C13—C14 | 1.502 (3) | C23—H23B | 0.9700 |
C13—H13A | 0.9700 | C24—O2C | 1.212 (3) |
C13—H13B | 0.9700 | C24—O2D | 1.307 (3) |
C14—O1C | 1.212 (3) | O2D—H2D | 0.8200 |
O2—S—O4 | 110.46 (12) | O1C—C14—C13 | 123.2 (2) |
O2—S—O1 | 109.13 (10) | O1D—C14—C13 | 113.09 (19) |
O4—S—O1 | 109.29 (10) | C14—O1D—H1D | 109.5 |
O2—S—O3 | 110.21 (9) | C21—O2B—H2B | 109.5 |
O4—S—O3 | 108.27 (10) | O2A—C21—O2B | 126.7 (2) |
O1—S—O3 | 109.45 (9) | O2A—C21—C22 | 122.8 (2) |
C11—O1B—H1B | 109.5 | O2B—C21—C22 | 110.53 (18) |
O1A—C11—O1B | 125.5 (2) | N21—C22—C21 | 108.38 (17) |
O1A—C11—C12 | 122.25 (19) | N21—C22—C23 | 110.74 (17) |
O1B—C11—C12 | 112.11 (18) | C21—C22—C23 | 110.62 (17) |
N11—C12—C11 | 107.46 (17) | N21—C22—H22 | 109.0 |
N11—C12—C13 | 110.81 (18) | C21—C22—H22 | 109.0 |
C11—C12—C13 | 115.85 (17) | C23—C22—H22 | 109.0 |
N11—C12—H12 | 107.5 | C22—N21—H21A | 109.5 |
C11—C12—H12 | 107.5 | C22—N21—H21B | 109.5 |
C13—C12—H12 | 107.5 | H21A—N21—H21B | 109.5 |
C12—N11—H11A | 109.5 | C22—N21—H21C | 109.5 |
C12—N11—H11B | 109.5 | H21A—N21—H21C | 109.5 |
H11A—N11—H11B | 109.5 | H21B—N21—H21C | 109.5 |
C12—N11—H11C | 109.5 | C24—C23—C22 | 112.88 (17) |
H11A—N11—H11C | 109.5 | C24—C23—H23A | 109.0 |
H11B—N11—H11C | 109.5 | C22—C23—H23A | 109.0 |
C14—C13—C12 | 112.10 (18) | C24—C23—H23B | 109.0 |
C14—C13—H13A | 109.2 | C22—C23—H23B | 109.0 |
C12—C13—H13A | 109.2 | H23A—C23—H23B | 107.8 |
C14—C13—H13B | 109.2 | O2C—C24—O2D | 124.65 (19) |
C12—C13—H13B | 109.2 | O2C—C24—C23 | 122.68 (19) |
H13A—C13—H13B | 107.9 | O2D—C24—C23 | 112.67 (18) |
O1C—C14—O1D | 123.66 (19) | C24—O2D—H2D | 109.5 |
O1A—C11—C12—N11 | 15.4 (3) | O2A—C21—C22—N21 | −8.0 (3) |
O1B—C11—C12—N11 | −168.38 (19) | O2B—C21—C22—N21 | 172.34 (17) |
O1A—C11—C12—C13 | 139.9 (2) | O2A—C21—C22—C23 | 113.6 (2) |
O1B—C11—C12—C13 | −43.9 (3) | O2B—C21—C22—C23 | −66.1 (2) |
N11—C12—C13—C14 | −85.3 (2) | N21—C22—C23—C24 | −64.7 (2) |
C11—C12—C13—C14 | 152.00 (19) | C21—C22—C23—C24 | 175.16 (18) |
C12—C13—C14—O1C | −33.4 (3) | C22—C23—C24—O2C | 3.9 (3) |
C12—C13—C14—O1D | 147.60 (19) | C22—C23—C24—O2D | −176.05 (19) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1B—H1B···O4i | 0.82 | 1.79 | 2.605 (2) | 174 |
N11—H11A···O2Cii | 0.89 | 1.97 | 2.760 (2) | 147 |
N11—H11B···O4iii | 0.89 | 2.20 | 2.837 (3) | 128 |
N11—H11C···O2 | 0.89 | 2.36 | 2.972 (3) | 126 |
O1D—H1D···O1ii | 0.82 | 1.85 | 2.673 (2) | 176 |
O2B—H2B···O3iv | 0.82 | 1.83 | 2.631 (2) | 166 |
N21—H21A···O1Cv | 0.89 | 2.14 | 2.898 (3) | 143 |
N21—H21A···O2C | 0.89 | 2.29 | 2.899 (2) | 126 |
N21—H21B···O3iii | 0.89 | 1.96 | 2.785 (3) | 154 |
N21—H21C···O1 | 0.89 | 2.12 | 2.906 (2) | 147 |
N21—H21C···O2 | 0.89 | 2.28 | 3.010 (3) | 140 |
O2D—H2D···O2v | 0.82 | 1.85 | 2.669 (2) | 175 |
Symmetry codes: (i) −x+2, y+1/2, −z+1/2; (ii) x, −y+3/2, z−1/2; (iii) x, y+1, z; (iv) −x+1, y+1/2, −z+1/2; (v) x, −y+3/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | 2C4H8NO4+·SO42− |
Mr | 364.29 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 16.774 (4), 5.9697 (9), 14.5276 (18) |
β (°) | 98.66 (2) |
V (Å3) | 1438.1 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.30 |
Crystal size (mm) | 0.5 × 0.4 × 0.2 |
Data collection | |
Diffractometer | Enraf-Nonius sealed tube diffractometer |
Absorption correction | ψ scan (North et al., 1968) |
Tmin, Tmax | 0.868, 0.943 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2616, 2502, 2113 |
Rint | 0.014 |
(sin θ/λ)max (Å−1) | 0.594 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.036, 0.107, 0.81 |
No. of reflections | 2502 |
No. of parameters | 212 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.38, −0.38 |
Computer programs: CAD-4 Software (Enraf-Nonius, 1989), CAD-4 Software, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), PLATON (Spek, 1999), SHELXL97.
O1A—C11 | 1.200 (3) | O2A—C21 | 1.194 (3) |
O1B—C11 | 1.311 (3) | O2B—C21 | 1.314 (3) |
C14—O1C | 1.212 (3) | C24—O2C | 1.212 (3) |
C14—O1D | 1.325 (3) | C24—O2D | 1.307 (3) |
O1A—C11—C12—N11 | 15.4 (3) | O2A—C21—C22—N21 | −8.0 (3) |
N11—C12—C13—C14 | −85.3 (2) | N21—C22—C23—C24 | −64.7 (2) |
C11—C12—C13—C14 | 152.00 (19) | C21—C22—C23—C24 | 175.16 (18) |
C12—C13—C14—O1C | −33.4 (3) | C22—C23—C24—O2C | 3.9 (3) |
C12—C13—C14—O1D | 147.60 (19) | C22—C23—C24—O2D | −176.05 (19) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1B—H1B···O4i | 0.82 | 1.79 | 2.605 (2) | 173.9 |
N11—H11A···O2Cii | 0.89 | 1.97 | 2.760 (2) | 146.7 |
N11—H11B···O4iii | 0.89 | 2.20 | 2.837 (3) | 128.1 |
N11—H11C···O2 | 0.89 | 2.36 | 2.972 (3) | 126.3 |
O1D—H1D···O1ii | 0.82 | 1.85 | 2.673 (2) | 176.1 |
O2B—H2B···O3iv | 0.82 | 1.83 | 2.631 (2) | 166.3 |
N21—H21A···O1Cv | 0.89 | 2.14 | 2.898 (3) | 142.7 |
N21—H21A···O2C | 0.89 | 2.29 | 2.899 (2) | 125.8 |
N21—H21B···O3iii | 0.89 | 1.96 | 2.785 (3) | 154.1 |
N21—H21C···O1 | 0.89 | 2.12 | 2.906 (2) | 147.0 |
N21—H21C···O2 | 0.89 | 2.28 | 3.010 (3) | 139.6 |
O2D—H2D···O2v | 0.82 | 1.85 | 2.669 (2) | 175.0 |
Symmetry codes: (i) −x+2, y+1/2, −z+1/2; (ii) x, −y+3/2, z−1/2; (iii) x, y+1, z; (iv) −x+1, y+1/2, −z+1/2; (v) x, −y+3/2, z+1/2. |
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Aspartic acid is an important compound among naturally occurring α-amino acids. The crystal structures of L-aspartic acid (Derissen et al., 1968), DL-aspartic acid (Rao, 1973), DL-aspartic acid hydrochloride (Dawson, 1977) and DL-aspartic acid nitrate monohydrate (Asath Bahadur & Rajaram, 1994) have been reported earlier. In the present study, DL-aspartic acid with sulfuric acid, (I), was undertaken.
In (I), there are two independent aspartic acid cations, A and B, which have the amino N11 and N21 atoms, respectively (Fig. 1). Their geometries are similar and agree well with those of DL-aspartic acid hydrochloride (Dawson, 1977). The molecule is made up of three four-atom planes consisting of C', Cα, Cβ, Cγ (plane 1), α-carboxyl group (plane 2) and the β-carboxyl group (plane 3). The mean deviations of the carbon skeleton from plane 1 are 0.167 and 0.030 Å for A and B, respectively. The Cγ is trans to the C' atom for both the molecules. The conformation angles ψ1 are 15.4 (3) and -8.0 (3)° for A and B, respectively (Table 1). This tendency of twisting of the C—N bond from the amino carboxyl plane is found in various amino acids (Lakshiminarayanan et al., 1967). The branched chain conformation angle χ1 is in a gauche II form for both molecules; the N11—C12—C13—C14 and N21—C22—C23—C24 torsion angle are -85.3 (2) and -64.7 (2)°, respectively.
The sulfate anion plays a vital role in forming hydrogen bonds with both the cations and stabilizing the structure (Fig. 2). The sulfate anion, as acceptor, links the O1B, O1D, N11, O2B, O2D and N21 atoms. The Oγ atom of each molecule links the amino N atom of the other molecule (Table 2). A bifurcated hydrogen bond is observed in the case of N21 with O1Cv and O2C, the latter being an intramolecular hydrogen bond. But an intramolecular hydrogen bond is not favoured in molecule A, since the χ22 for A and B are -33.4 (3) and 3.9 (3)°, respectively. A chelated three-centre hydrogen bond is observed in the case of the amino N21 atom of molecule B with the sulfate O1 and O2 atoms (Jeffrey & Saenger, 1991). An infinite chain of hydrogen bonds runs along the b axis, linking the sulfate anion and the N21 atom.