Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270101021631/gd1181sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S0108270101021631/gd1181Isup2.hkl |
CCDC reference: 182040
Melamine was dissolved in a 20% solution of acetic acid and the resulting solution was slowly evaporated. After several days, colourless crystals of (I) appeared.
H atoms bonded to C and N were treated as riding, with C—H = 0.96 and N—H = 0.86 Å. The coordinates of H atoms bonded to O were refined, and the resulting range of O—H distances was 0.80 (2)–0.83 (2) Å.
Data collection: XSCANS (Siemens, 1991); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Sheldrick, 1990); software used to prepare material for publication: SHELXL97.
C3H7N6+·C2H3O2−·H2O·C2H4O2 | F(000) = 560 |
Mr = 264.26 | Dx = 1.393 Mg m−3 Dm = 1.39 Mg m−3 Dm measured by flotation |
Triclinic, P1 | Melting point: decomposition K |
a = 6.859 (1) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 12.427 (2) Å | Cell parameters from 69 reflections |
c = 15.307 (3) Å | θ = 9–16° |
α = 92.31 (3)° | µ = 0.12 mm−1 |
β = 95.87 (3)° | T = 293 K |
γ = 103.36 (3)° | Parallelepiped, colourless |
V = 1260.0 (4) Å3 | 0.33 × 0.18 × 0.15 mm |
Z = 4 |
Siemens P4 diffractometer | 2141 reflections with I > 2σ(I) |
Radiation source: fine-focus sealed tube | Rint = 0.017 |
Graphite monochromator | θmax = 25.1°, θmin = 2.7° |
ω/2θ scans | h = −8→7 |
Absorption correction: analytical face-indexed (SHELXTL; Sheldrick, 1990) | k = −14→14 |
Tmin = 0.962, Tmax = 0.983 | l = −18→18 |
7979 measured reflections | 2 standard reflections every 50 reflections |
4252 independent reflections | intensity decay: 0.8% |
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)] = 0.037 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.057 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | w = 1/[σ2(Fo2) + (0.012P)2 + 0.0133P] where P = (Fo2 + 2Fc2)/3 |
4252 reflections | (Δ/σ)max = 0.001 |
347 parameters | Δρmax = 0.15 e Å−3 |
7 restraints | Δρmin = −0.14 e Å−3 |
C3H7N6+·C2H3O2−·H2O·C2H4O2 | γ = 103.36 (3)° |
Mr = 264.26 | V = 1260.0 (4) Å3 |
Triclinic, P1 | Z = 4 |
a = 6.859 (1) Å | Mo Kα radiation |
b = 12.427 (2) Å | µ = 0.12 mm−1 |
c = 15.307 (3) Å | T = 293 K |
α = 92.31 (3)° | 0.33 × 0.18 × 0.15 mm |
β = 95.87 (3)° |
Siemens P4 diffractometer | 2141 reflections with I > 2σ(I) |
Absorption correction: analytical face-indexed (SHELXTL; Sheldrick, 1990) | Rint = 0.017 |
Tmin = 0.962, Tmax = 0.983 | 2 standard reflections every 50 reflections |
7979 measured reflections | intensity decay: 0.8% |
4252 independent reflections |
R[F2 > 2σ(F2)] = 0.037 | 7 restraints |
wR(F2) = 0.057 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.00 | Δρmax = 0.15 e Å−3 |
4252 reflections | Δρmin = −0.14 e Å−3 |
347 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 | ||
N1 | 0.7302 (2) | 0.73967 (13) | 0.07260 (10) | 0.0383 (4) | |
C1 | 0.7510 (3) | 0.74024 (16) | −0.01294 (13) | 0.0390 (5) | |
N2 | 0.7618 (2) | 0.83469 (12) | −0.05616 (10) | 0.0395 (4) | |
H2 | 0.7757 | 0.8342 | −0.1114 | 0.047* | |
C2 | 0.7506 (3) | 0.92940 (16) | −0.01208 (13) | 0.0391 (5) | |
N3 | 0.7294 (2) | 0.93343 (12) | 0.07279 (10) | 0.0399 (4) | |
C3 | 0.7167 (3) | 0.83667 (16) | 0.11264 (12) | 0.0400 (5) | |
N4 | 0.7604 (2) | 0.64910 (13) | −0.05881 (10) | 0.0472 (4) | |
H4NA | 0.7531 | 0.5881 | −0.0334 | 0.057* | |
H4NB | 0.7739 | 0.6510 | −0.1140 | 0.057* | |
N5 | 0.7608 (2) | 1.01746 (13) | −0.05790 (11) | 0.0517 (5) | |
H5NA | 0.7537 | 1.0793 | −0.0327 | 0.062* | |
H5NB | 0.7746 | 1.0132 | −0.1131 | 0.062* | |
N6 | 0.6870 (2) | 0.83755 (13) | 0.19614 (10) | 0.0515 (5) | |
H6NA | 0.6767 | 0.7778 | 0.2236 | 0.062* | |
H6NB | 0.6778 | 0.8978 | 0.2233 | 0.062* | |
N7 | 0.7479 (2) | 0.43301 (12) | 0.02400 (9) | 0.0363 (4) | |
C4 | 0.7303 (3) | 0.43256 (15) | 0.10949 (12) | 0.0395 (5) | |
N8 | 0.7258 (2) | 0.33975 (12) | 0.15358 (10) | 0.0420 (4) | |
H8 | 0.7183 | 0.3415 | 0.2093 | 0.050* | |
C5 | 0.7333 (3) | 0.24469 (16) | 0.10974 (12) | 0.0398 (5) | |
N9 | 0.7468 (2) | 0.23932 (12) | 0.02295 (10) | 0.0370 (4) | |
C6 | 0.7577 (3) | 0.33557 (16) | −0.01601 (12) | 0.0376 (5) | |
N10 | 0.7144 (3) | 0.52247 (13) | 0.15485 (10) | 0.0538 (5) | |
H10N | 0.7153 | 0.5827 | 0.1289 | 0.065* | |
H11N | 0.7031 | 0.5207 | 0.2102 | 0.065* | |
N11 | 0.7217 (2) | 0.15435 (13) | 0.15410 (10) | 0.0469 (5) | |
H12N | 0.7229 | 0.0924 | 0.1272 | 0.056* | |
H13N | 0.7131 | 0.1577 | 0.2098 | 0.056* | |
N12 | 0.7821 (2) | 0.33424 (13) | −0.10091 (9) | 0.0486 (5) | |
H14N | 0.7901 | 0.2739 | −0.1283 | 0.058* | |
H15N | 0.7898 | 0.3937 | −0.1285 | 0.058* | |
O11 | 0.2293 (2) | 0.14468 (11) | 0.23549 (9) | 0.0601 (4) | |
O12 | 0.2431 (3) | 0.32386 (12) | 0.23777 (10) | 0.0740 (5) | |
C12 | 0.2128 (4) | 0.23704 (18) | 0.37108 (13) | 0.0604 (6) | |
H12A | 0.2037 | 0.3094 | 0.3920 | 0.091* | |
H12B | 0.3307 | 0.2197 | 0.4009 | 0.091* | |
H12C | 0.0949 | 0.1832 | 0.3826 | 0.091* | |
C11 | 0.2267 (4) | 0.23530 (19) | 0.27535 (14) | 0.0533 (6) | |
O21 | 0.1982 (2) | −0.12903 (12) | 0.21138 (9) | 0.0630 (5) | |
O22 | 0.1663 (3) | −0.02558 (13) | 0.32902 (10) | 0.0701 (5) | |
H222 | 0.193 (4) | 0.0254 (18) | 0.2955 (15) | 0.105* | |
C21 | 0.1693 (3) | −0.12000 (18) | 0.28757 (14) | 0.0494 (6) | |
C22 | 0.1230 (4) | −0.21590 (18) | 0.34284 (14) | 0.0704 (7) | |
H22A | 0.0044 | −0.2684 | 0.3159 | 0.106* | |
H22B | 0.0999 | −0.1908 | 0.4002 | 0.106* | |
H22C | 0.2347 | −0.2506 | 0.3482 | 0.106* | |
O31 | 0.7270 (2) | 0.31449 (12) | 0.33567 (9) | 0.0583 (4) | |
O32 | 0.7976 (2) | 0.49755 (12) | 0.34265 (9) | 0.0603 (4) | |
C32 | 0.7335 (4) | 0.4099 (2) | 0.47417 (13) | 0.0736 (8) | |
H32A | 0.6244 | 0.3506 | 0.4863 | 0.110* | |
H32B | 0.7074 | 0.4796 | 0.4922 | 0.110* | |
H32C | 0.8569 | 0.4020 | 0.5060 | 0.110* | |
C31 | 0.7519 (3) | 0.40599 (19) | 0.37780 (14) | 0.0516 (6) | |
O41 | 0.6790 (3) | 0.04125 (12) | 0.30406 (9) | 0.0705 (5) | |
O42 | 0.6978 (3) | 0.14033 (13) | 0.42910 (10) | 0.0705 (5) | |
H421 | 0.724 (4) | 0.192 (2) | 0.4006 (17) | 0.106* | |
C41 | 0.6890 (4) | 0.04655 (19) | 0.38352 (15) | 0.0544 (6) | |
C42 | 0.6989 (4) | −0.04788 (19) | 0.43843 (14) | 0.0727 (8) | |
H42A | 0.7579 | −0.0993 | 0.4081 | 0.109* | |
H42B | 0.5653 | −0.0845 | 0.4495 | 0.109* | |
H42C | 0.7800 | −0.0211 | 0.4933 | 0.109* | |
O1W | 0.5787 (3) | 0.66472 (14) | 0.31972 (14) | 0.0789 (5) | |
H1W1 | 0.609 (4) | 0.614 (2) | 0.3467 (18) | 0.118* | |
H2W1 | 0.460 (2) | 0.639 (2) | 0.312 (2) | 0.118* | |
O2W | 0.1872 (3) | 0.52752 (13) | 0.26407 (14) | 0.0756 (5) | |
H1W2 | 0.207 (4) | 0.4646 (16) | 0.2660 (18) | 0.113* | |
H2W2 | 0.082 (3) | 0.517 (2) | 0.2843 (19) | 0.113* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0425 (10) | 0.0321 (10) | 0.0426 (9) | 0.0136 (8) | 0.0045 (8) | 0.0023 (8) |
C1 | 0.0422 (13) | 0.0289 (11) | 0.0481 (12) | 0.0145 (10) | 0.0022 (10) | 0.0022 (9) |
N2 | 0.0552 (11) | 0.0284 (9) | 0.0368 (9) | 0.0127 (8) | 0.0081 (8) | 0.0001 (7) |
C2 | 0.0481 (13) | 0.0244 (11) | 0.0456 (11) | 0.0108 (10) | 0.0030 (10) | 0.0039 (9) |
N3 | 0.0498 (11) | 0.0257 (9) | 0.0468 (10) | 0.0132 (8) | 0.0086 (8) | 0.0009 (8) |
C3 | 0.0480 (13) | 0.0320 (12) | 0.0417 (11) | 0.0115 (10) | 0.0084 (10) | 0.0030 (9) |
N4 | 0.0660 (12) | 0.0377 (10) | 0.0401 (9) | 0.0178 (9) | 0.0025 (9) | 0.0041 (8) |
N5 | 0.0683 (13) | 0.0382 (11) | 0.0524 (11) | 0.0193 (10) | 0.0096 (10) | 0.0002 (9) |
N6 | 0.0778 (14) | 0.0326 (10) | 0.0480 (10) | 0.0188 (10) | 0.0112 (10) | 0.0034 (8) |
N7 | 0.0467 (11) | 0.0259 (9) | 0.0364 (9) | 0.0088 (8) | 0.0044 (8) | 0.0019 (7) |
C4 | 0.0523 (14) | 0.0282 (11) | 0.0377 (11) | 0.0118 (10) | 0.0005 (10) | −0.0038 (9) |
N8 | 0.0624 (12) | 0.0279 (9) | 0.0354 (9) | 0.0116 (9) | 0.0020 (9) | 0.0003 (7) |
C5 | 0.0477 (13) | 0.0316 (12) | 0.0404 (11) | 0.0097 (10) | 0.0052 (10) | 0.0035 (9) |
N9 | 0.0486 (11) | 0.0210 (9) | 0.0428 (9) | 0.0095 (8) | 0.0083 (8) | 0.0042 (7) |
C6 | 0.0442 (13) | 0.0311 (11) | 0.0369 (10) | 0.0098 (10) | 0.0016 (10) | 0.0004 (9) |
N10 | 0.0857 (14) | 0.0334 (10) | 0.0453 (10) | 0.0195 (10) | 0.0089 (10) | 0.0036 (8) |
N11 | 0.0757 (13) | 0.0290 (9) | 0.0371 (9) | 0.0152 (9) | 0.0040 (9) | 0.0036 (8) |
N12 | 0.0790 (14) | 0.0337 (10) | 0.0365 (9) | 0.0172 (10) | 0.0133 (9) | 0.0023 (8) |
O11 | 0.0890 (12) | 0.0428 (9) | 0.0515 (9) | 0.0210 (9) | 0.0096 (9) | 0.0019 (8) |
O12 | 0.1318 (15) | 0.0412 (9) | 0.0580 (10) | 0.0334 (10) | 0.0206 (10) | 0.0113 (8) |
C12 | 0.0780 (17) | 0.0528 (15) | 0.0533 (14) | 0.0205 (14) | 0.0094 (13) | 0.0042 (12) |
C11 | 0.0709 (17) | 0.0421 (14) | 0.0503 (13) | 0.0189 (12) | 0.0100 (12) | 0.0014 (11) |
O21 | 0.0918 (13) | 0.0504 (10) | 0.0501 (9) | 0.0229 (9) | 0.0114 (9) | −0.0010 (8) |
O22 | 0.1105 (14) | 0.0511 (11) | 0.0513 (10) | 0.0230 (11) | 0.0130 (10) | 0.0031 (8) |
C21 | 0.0632 (16) | 0.0411 (13) | 0.0447 (12) | 0.0184 (12) | −0.0015 (12) | −0.0023 (10) |
C22 | 0.103 (2) | 0.0556 (15) | 0.0556 (14) | 0.0239 (15) | 0.0103 (14) | 0.0035 (12) |
O31 | 0.0830 (12) | 0.0458 (9) | 0.0453 (8) | 0.0139 (9) | 0.0073 (8) | −0.0009 (8) |
O32 | 0.0874 (12) | 0.0443 (9) | 0.0511 (9) | 0.0192 (9) | 0.0079 (8) | 0.0033 (8) |
C32 | 0.098 (2) | 0.0642 (17) | 0.0515 (15) | 0.0017 (15) | 0.0193 (14) | −0.0027 (13) |
C31 | 0.0599 (16) | 0.0484 (15) | 0.0469 (13) | 0.0139 (12) | 0.0065 (12) | 0.0012 (11) |
O41 | 0.1204 (15) | 0.0510 (10) | 0.0458 (9) | 0.0315 (10) | 0.0088 (10) | 0.0066 (8) |
O42 | 0.1133 (15) | 0.0493 (11) | 0.0466 (9) | 0.0133 (11) | 0.0109 (10) | 0.0050 (8) |
C41 | 0.0654 (16) | 0.0465 (15) | 0.0518 (14) | 0.0119 (13) | 0.0113 (12) | 0.0043 (12) |
C42 | 0.108 (2) | 0.0598 (16) | 0.0559 (14) | 0.0281 (16) | 0.0170 (15) | 0.0101 (13) |
O1W | 0.0855 (13) | 0.0611 (12) | 0.0975 (14) | 0.0249 (11) | 0.0231 (13) | 0.0166 (10) |
O2W | 0.0815 (14) | 0.0488 (11) | 0.1016 (14) | 0.0178 (10) | 0.0233 (11) | 0.0169 (11) |
N1—C1 | 1.332 (2) | N12—H15N | 0.8600 |
N1—C3 | 1.357 (2) | O11—C11 | 1.264 (2) |
C1—N4 | 1.326 (2) | O12—C11 | 1.250 (2) |
C1—N2 | 1.361 (2) | C12—C11 | 1.478 (3) |
N2—C2 | 1.354 (2) | C12—H12A | 0.9600 |
N2—H2 | 0.8600 | C12—H12B | 0.9600 |
C2—N5 | 1.316 (2) | C12—H12C | 0.9600 |
C2—N3 | 1.322 (2) | O21—C21 | 1.208 (2) |
N3—C3 | 1.359 (2) | O22—C21 | 1.317 (2) |
C3—N6 | 1.315 (2) | O22—H222 | 0.831 (16) |
N4—H4NA | 0.8600 | C21—C22 | 1.483 (3) |
N4—H4NB | 0.8600 | C22—H22A | 0.9600 |
N5—H5NA | 0.8600 | C22—H22B | 0.9600 |
N5—H5NB | 0.8600 | C22—H22C | 0.9600 |
N6—H6NA | 0.8600 | O31—C31 | 1.252 (2) |
N6—H6NB | 0.8600 | O32—C31 | 1.266 (2) |
N7—C4 | 1.326 (2) | C32—C31 | 1.493 (3) |
N7—C6 | 1.354 (2) | C32—H32A | 0.9600 |
C4—N10 | 1.324 (2) | C32—H32B | 0.9600 |
C4—N8 | 1.355 (2) | C32—H32C | 0.9600 |
N8—C5 | 1.349 (2) | O41—C41 | 1.209 (2) |
N8—H8 | 0.8600 | O42—C41 | 1.320 (3) |
C5—N11 | 1.326 (2) | O42—H421 | 0.79 (3) |
C5—N9 | 1.341 (2) | C41—C42 | 1.481 (3) |
N9—C6 | 1.348 (2) | C42—H42A | 0.9600 |
C6—N12 | 1.327 (2) | C42—H42B | 0.9600 |
N10—H10N | 0.8600 | C42—H42C | 0.9600 |
N10—H11N | 0.8600 | O1W—H1W1 | 0.823 (16) |
N11—H12N | 0.8600 | O1W—H2W1 | 0.798 (16) |
N11—H13N | 0.8600 | O2W—H1W2 | 0.825 (16) |
N12—H14N | 0.8600 | O2W—H2W2 | 0.798 (16) |
C1—N1—C3 | 116.4 (2) | C6—N12—H14N | 120.0 |
N4—C1—N1 | 121.3 (2) | C6—N12—H15N | 120.0 |
N4—C1—N2 | 117.92 (18) | H14N—N12—H15N | 120.0 |
N1—C1—N2 | 120.8 (2) | C11—C12—H12A | 109.5 |
C2—N2—C1 | 119.9 (2) | C11—C12—H12A | 109.5 |
C2—N2—H2 | 120.0 | H12A—C12—H12B | 109.5 |
C1—N2—H2 | 120.0 | C11—C12—H12C | 109.5 |
N5—C2—N3 | 121.40 (19) | H12A—C12—H12C | 109.5 |
N5—C2—N2 | 116.78 (18) | H12B—C12—H12C | 109.5 |
N3—C2—N2 | 121.8 (2) | O12—C11—O11 | 122.7 (2) |
C2—N3—C3 | 116.0 (2) | O12—C11—C12 | 118.9 (2) |
N6—C3—N1 | 117.91 (18) | O11—C11—C12 | 118.3 (2) |
N6—C3—N3 | 117.08 (18) | C21—O22—H222 | 109.3 (19) |
N1—C3—N3 | 125.0 (2) | O21—C21—O22 | 123.9 (2) |
C1—N4—H4NA | 120.0 | O21—C21—C22 | 123.1 (2) |
C1—N4—H4NB | 120.0 | O22—C21—C22 | 112.96 (19) |
H4NA—N4—H4NB | 120.0 | C21—C22—H22A | 109.5 |
C2—N5—H5NA | 120.0 | C21—C22—H22B | 109.5 |
C2—N5—H5NB | 120.0 | H22A—C22—H22B | 109.5 |
H5NA—N5—H5NB | 120.0 | C21—C22—H22C | 109.5 |
C3—N6—H6NA | 120.0 | H22A—C22—H22C | 109.5 |
C3—N6—H6NB | 120.0 | H22B—C22—H22C | 109.5 |
H6NA—N6—H6NB | 120.0 | C31—C32—H32A | 109.5 |
C4—N7—C6 | 116.1 (2) | C31—C32—H32B | 109.5 |
N10—C4—N7 | 121.25 (17) | H32A—C32—H32B | 109.5 |
N10—C4—N8 | 117.42 (17) | C31—C32—H32C | 109.5 |
N7—C4—N8 | 121.3 (2) | H32A—C32—H32C | 109.5 |
C5—N8—C4 | 119.8 (2) | H32B—C32—H32C | 109.5 |
C5—N8—H8 | 120.1 | O31—C31—O32 | 122.8 (2) |
C4—N8—H8 | 120.1 | O31—C31—C32 | 119.8 (2) |
N11—C5—N9 | 119.92 (18) | O32—C31—C32 | 117.4 (2) |
N11—C5—N8 | 118.41 (17) | C41—O42—H421 | 112 (2) |
N9—C5—N8 | 121.7 (2) | O41—C41—O42 | 121.7 (2) |
C5—N9—C6 | 115.3 (2) | O41—C41—C42 | 124.3 (2) |
N12—C6—N9 | 116.72 (17) | O42—C41—C42 | 114.01 (19) |
N12—C6—N7 | 117.51 (17) | C41—C42—H42A | 109.5 |
N9—C6—N7 | 125.8 (2) | C41—C42—H42B | 109.5 |
C4—N10—H10N | 120.0 | H42A—C42—H42B | 109.5 |
C4—N10—H11N | 120.0 | C41—C42—H42C | 109.5 |
H10N—N10—H11N | 120.0 | H42A—C42—H42C | 109.5 |
C5—N11—H12N | 120.0 | H42B—C42—H42C | 109.5 |
C5—N11—H13N | 120.0 | H1W1—O1W—H2W1 | 97 (2) |
H12N—N11—H13N | 120.0 | H1W2—O2W—H2W2 | 99 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2···O11i | 0.86 | 1.93 | 2.773 (2) | 168 |
N4—H4NA···N7 | 0.86 | 2.14 | 3.002 (2) | 176 |
N4—H4NB···O12i | 0.86 | 1.93 | 2.772 (2) | 166 |
N5—H5NA···N9ii | 0.86 | 2.14 | 3.002 (2) | 176 |
N5—H5NB···O21i | 0.86 | 2.12 | 2.782 (2) | 133 |
N6—H6NA···O1W | 0.86 | 2.13 | 2.936 (2) | 157 |
N6—H6NB···O41ii | 0.86 | 2.13 | 2.981 (2) | 173 |
N8—H8···O31 | 0.86 | 1.97 | 2.817 (2) | 167 |
N10—H10N···N1 | 0.86 | 2.15 | 3.008 (2) | 176 |
N10—H11N···O32 | 0.86 | 2.12 | 2.916 (2) | 155 |
N11—H12N···N3iii | 0.86 | 2.13 | 2.982 (2) | 175 |
N11—H13N···O41 | 0.86 | 2.08 | 2.746 (2) | 134 |
N12—H14N···O21iv | 0.86 | 2.18 | 3.040 (2) | 174 |
N12—H15N···O2Wi | 0.86 | 2.33 | 3.085 (2) | 146 |
O22—H222···O11 | 0.83 (2) | 1.76 (2) | 2.581 (2) | 171 (3) |
O42—H421···O31 | 0.79 (3) | 1.85 (2) | 2.622 (2) | 167 (3) |
O1W—H1W1···O32 | 0.82 (2) | 2.16 (2) | 2.844 (2) | 141 (3) |
O1W—H2W1···O2W | 0.80 (2) | 2.10 (2) | 2.853 (2) | 158 (3) |
O2W—H1W2···O12 | 0.82 (2) | 1.86 (2) | 2.667 (2) | 165 (3) |
O2W—H2W2···O32v | 0.80 (2) | 2.20 (2) | 2.993 (2) | 177 (3) |
Symmetry codes: (i) −x+1, −y+1, −z; (ii) x, y+1, z; (iii) x, y−1, z; (iv) −x+1, −y, −z; (v) x−1, y, z. |
Experimental details
Crystal data | |
Chemical formula | C3H7N6+·C2H3O2−·H2O·C2H4O2 |
Mr | 264.26 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 293 |
a, b, c (Å) | 6.859 (1), 12.427 (2), 15.307 (3) |
α, β, γ (°) | 92.31 (3), 95.87 (3), 103.36 (3) |
V (Å3) | 1260.0 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.12 |
Crystal size (mm) | 0.33 × 0.18 × 0.15 |
Data collection | |
Diffractometer | Siemens P4 diffractometer |
Absorption correction | Analytical face-indexed (SHELXTL; Sheldrick, 1990) |
Tmin, Tmax | 0.962, 0.983 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 7979, 4252, 2141 |
Rint | 0.017 |
(sin θ/λ)max (Å−1) | 0.596 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.037, 0.057, 1.00 |
No. of reflections | 4252 |
No. of parameters | 347 |
No. of restraints | 7 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.15, −0.14 |
Computer programs: XSCANS (Siemens, 1991), XSCANS, SHELXS97 (Sheldrick, 1997), SHELXL97 (Sheldrick, 1997), SHELXTL (Sheldrick, 1990), SHELXL97.
O11—C11 | 1.264 (2) | O31—C31 | 1.252 (2) |
O12—C11 | 1.250 (2) | O32—C31 | 1.266 (2) |
C12—C11 | 1.478 (3) | C32—C31 | 1.493 (3) |
O21—C21 | 1.208 (2) | O41—C41 | 1.209 (2) |
O22—C21 | 1.317 (2) | O42—C41 | 1.320 (3) |
C21—C22 | 1.483 (3) | C41—C42 | 1.481 (3) |
C1—N1—C3 | 116.4 (2) | C4—N7—C6 | 116.1 (2) |
N1—C1—N2 | 120.8 (2) | N7—C4—N8 | 121.3 (2) |
C2—N2—C1 | 119.9 (2) | C5—N8—C4 | 119.8 (2) |
N3—C2—N2 | 121.8 (2) | N9—C5—N8 | 121.7 (2) |
C2—N3—C3 | 116.0 (2) | C5—N9—C6 | 115.3 (2) |
N1—C3—N3 | 125.0 (2) | N9—C6—N7 | 125.8 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2···O11i | 0.86 | 1.93 | 2.773 (2) | 168 |
N4—H4NA···N7 | 0.86 | 2.14 | 3.002 (2) | 176 |
N4—H4NB···O12i | 0.86 | 1.93 | 2.772 (2) | 166 |
N5—H5NA···N9ii | 0.86 | 2.14 | 3.002 (2) | 176 |
N5—H5NB···O21i | 0.86 | 2.12 | 2.782 (2) | 133 |
N6—H6NA···O1W | 0.86 | 2.13 | 2.936 (2) | 157 |
N6—H6NB···O41ii | 0.86 | 2.13 | 2.981 (2) | 173 |
N8—H8···O31 | 0.86 | 1.97 | 2.817 (2) | 167 |
N10—H10N···N1 | 0.86 | 2.15 | 3.008 (2) | 176 |
N10—H11N···O32 | 0.86 | 2.12 | 2.916 (2) | 155 |
N11—H12N···N3iii | 0.86 | 2.13 | 2.982 (2) | 175 |
N11—H13N···O41 | 0.86 | 2.08 | 2.746 (2) | 134 |
N12—H14N···O21iv | 0.86 | 2.18 | 3.040 (2) | 174 |
N12—H15N···O2Wi | 0.86 | 2.33 | 3.085 (2) | 146 |
O22—H222···O11 | 0.83 (2) | 1.76 (2) | 2.581 (2) | 171 (3) |
O42—H421···O31 | 0.79 (3) | 1.85 (2) | 2.622 (2) | 167 (3) |
O1W—H1W1···O32 | 0.82 (2) | 2.16 (2) | 2.844 (2) | 141 (3) |
O1W—H2W1···O2W | 0.80 (2) | 2.10 (2) | 2.853 (2) | 158 (3) |
O2W—H1W2···O12 | 0.82 (2) | 1.86 (2) | 2.667 (2) | 165 (3) |
O2W—H2W2···O32v | 0.80 (2) | 2.20 (2) | 2.993 (2) | 177 (3) |
Symmetry codes: (i) −x+1, −y+1, −z; (ii) x, y+1, z; (iii) x, y−1, z; (iv) −x+1, −y, −z; (v) x−1, y, z. |
This study forms part of our investigation of the characterization of the hydrogen bonds formed by the melamine molecule in the solid state (Janczak & Perpétuo, 2001a,b,c,d). The melamine molecule and its organic and inorganic complexes or salts can, via multiple hydrogen bonds, develop supramolecular structures by self-assembly of components which contain complementary arrays of hydrogen-bonding sites (MacDonald & Whitesides, 1994; Row, 1999; Krische & Lehn, 2000; Sherrington & Taskinen, 2001). To expand understanding of the solid state physical organic chemistry of compounds containing multiple and different hydrogen-bonding systems, we have studied the solid state structure of single-protonated melaminium acetate monohydrate acetic acid solvate, (I), and the results are presented here. \sch
The asymmetric unit of (I) consists of two molecules, namely two melaminium residues protonated at one ring N atom, two acetate anions, two acetic acid molecules and two water molecules (Fig. 1). The two independent melaminium cations do not differ significantly, but the six-membered aromatic rings exhibit significant distortion from the ideal hexagonal form. The internal C—N—C angle at the protonated N atom (N2) is significantly greater than the other two ring C—N—C angles (Table 1). This is a result of the steric effect of a lone-pair electron, predicted by the valence-shell electron pair repulsion theory (VSEPR; Gillespie, 1963, 1992).
As a result of the protonation of the melamine ring at atom N2, the internal N—C—N angle containing only non-protonated N atoms is significantly greater than either of the N—C—N angles containing both protonated and non-protonated N atoms. This correlation between the internal C—N—C angles within the melaminium rings is quite similar to those reported for the crystals of barbituric acid with melamine (Zerkowski et al., 1994), melaminium phthalate (Janczak & Perpétuo, 2001a), melaminium chloride hemihydrate (Janczak & Perpétuo, 2001c) and bis(melaminium) sulfate dihydrate (Janczak & Perpétuo, 2001 d), i.e. those singly protonated melaminium salts that have been structurally characterized to date.
The melaminium residues in the crystal of (I) are involved in nine hydrogen bonds, in seven of them as donor H and in the remaining two as acceptor H. The four N—H···N bonds link the melaminium residue with two neighbouring melaminium residues to form a chain (Fig. 2), while the five N—H···O bonds link a melaminium residue with two acetate ions, two acetic acid molecules and one water molecule. The N—H···N hydrogen bonds are much more linear than the N—H···O bonds.
The geometries of the two independent acetate ions do not differ significantly. The C—O bond lengths in the acetate moieties indicate delocalization of the charge on both O atoms, since the C—O bond lengths are intermediate between single Csp2—O and double Csp2═O, and correlate well with values for carboxylate anions (1.247–1.262 Å; Allen et al., 1987). One of the two independent acetate ions is involved as acceptor in four hydrogen bonds (O11 and O12), while the other acetate ion is involved in five hydrogen bonds.
Both independent acetic acid molecules exhibit similar geometry. The OH group of the COOH in both acetic acid molecules joins the acetate ions via O—H···O hydrogen bonds. The carbonyl O atom of the COOH groups acts as acceptor in hydrogen bonds with the amine groups of two different melaminium residues. The slight differences in C—O distances for equivalent bonds in the acetate ions, as well as in the acetic acid molecules, correlate with the number and strengh of the hydrogen bonds in which the O atoms are involved (see Table 2).
The water molecules form a hydrogen-bonded dimeric structure (O1W-H2W1···O2W), with an O···O distance of 2.853 (3) Å, joining the hydrogen-bonded acetic acid-acetate moieties. The first water molecule (O1W) is involved in three hydrogen bonds, in two of which it acts as donor H, with O2W of a water molecule and O32 of an acetate ion, and in the other as acceptor H, with the amine group of a melaminium residue. The second water molecule is involved in four hydrogen bonds, with two acetate ions, a water molecule and an amine group of a melaminium residue. Details of this hydrogen-bonding geometry are given in Table 2.
In the crystal of (I), the melaminium residues form complementary planar positively charged chains interconnected by N—H···N hydrogen bonds, and these chains form stacks parallel to the (001) plane (Fig. 3). Within one stack, the melaminium residues are separated by ~3.25 Å. This is slightly shorter than the distance between π-aromatic ring systems (~3.4 Å; Pauling, 1960) and indicates π–π interaction between the melaminium rings. The hydrogen-bonded acetic acid-acetate moieties are interconnected by the dimeric structure of the hydrogen-bonded water, forming negatively charged layers that are located parallel to the (001) plane. These oppositely charged moieties are extensively interconnected by multiple hydrogen bonds to form columnar supramolecular aggregates which are aligned along the a axis.