research communications
H,4H-1,2,3-oxathiazin-3-ide
and Hirshfeld surface analysis of 2-amino-3-hydroxypyridin-1-ium 6-methyl-2,2,4-trioxo-2aDepartment of Fundamental Sciences, Faculty of Engineering, Samsun University, Samsun, 55420, Turkey, bPG Department of Chemistry, Langat Singh College, B. R. A. Bihar University, Muzaffarpur, Bihar-842001, India, cDepartment of Chemistry, Faculty of Arts and Sciences, Ondokuz Mayıs, University, Samsun, 55200, Turkey, dDepartment of Physics, Faculty of Arts and Sciences, Ondokuz Mayıs, University, Samsun, 55200, Turkey, and eDepartment of Chemistry, Volodymyrska str., 64, National Taras Shevchenko University, 01601 Kyiv, Ukraine
*Correspondence e-mail: sevgi.kansiz85@gmail.com, igolenya@ua.fm
The 5H7N2O+·C4H4NO4S−, contains one cation and one anion. The 6-methyl-2,2,4-trioxo-2H,4H-1,2,3-oxathiazin-3-ide anion adopts an with the S atom as the flap. In the crystal, the anions and cations are held together by N—H⋯O, N—H⋯N, O—H⋯O and C—H⋯O hydrogen bonds, thus forming a three-dimensional structure. The Hirshfeld surface analysis and fingerprint plots reveal that the crystal packing is dominated by O⋯H/H⋯O (43.1%) and H⋯H (24.2%) contacts.
of the title compound, CKeywords: crystal structure; acesulfame; 2-amino-3-hydroxypyridine; hydrogen bonding; Hirshfeld surface analysis.
CCDC reference: 1920140
1. Chemical context
Food additives are substances added intentionally to foodstuffs to perform certain functions such as to impart colour, to sweeten or preserve. They play an essential role in the modern food industry, supporting quality and safety. In this context, artificial sweeteners are widely used in food, beverage, confectionery and pharmaceutical products throughout the world (Clauss & Jensen, 1973; Ni et al., 2009). Oxathiazinone dioxide, 6-methyl-1,2,3-oxathiazin- 4(3H)-one 2,2-dioxide and also known as 6-methyl-3,4-dihydro-1,2,3- oxathiazin-4-one 2,2-dioxide or acesulfame, has been widely used as a non-caloric artificial sweetener (Duffy & Anderson, 1998) since 1988, after the FDA (US Food and Drug Administration) granted approval. Many countries have approved the use of acesulfame-K in soft drinks, toothpaste, candies, mouthwash, cosmetics and pharmacological preparations (Mukherjee & Chakrabarti, 1997). The chemistry of acesulfame is of interest not only because of its biological importance but also in relation to its coordination properties, since the acesulfame anion offers different donor atoms to metal ions, namely the imino nitrogen, ring oxygen, one carbonyl and two sulfonyl oxygen atoms. To advance the knowledge of such compounds, we report the synthesis, single determination and Hirshfeld surface analysis of the 2-amino-3-hydroxypyridinium acesulfamate salt (I).
2. Structural commentary
A view of the with the atom-numbering scheme is shown in Fig. 1. In the acesulfamate anion, the bond dimensions correspond to the given with double bonds C1=O4 and C2=C3 and a single bond C1—C2 (Table 1). A relatively short N1—C1 bond indicates strong π-conjugation in the N1—C1=O4 fragment. Overall, the bond lengths in this anion compare well with those observed in other acesulfamate salts known from the literature (Yıldırım et al., 2019; Kansız et al., 2019). The six-membered acesulfamate ring adopts an with atom S1 as the flap; its deviation from the basal plane is 0.555 (1) Å. The basal plane of the envelope is slightly twisted, with an O1—C3—C1—N1 torsion angle of 2.2 (2)°. The cyclic bond lengths in the 2-amino-3-hydroxypyridinium cation agree well with its aromatic nature. The short N3—C5 distance indicates strong conjugation of the amino N3 atom with the acceptor π-system of the pyridinium ring. The cation is almost planar, the largest deviation from the least-squares plane of 0.008 (2) Å is observed for atom C6. The least-squares planes through the cation and the basal atoms of anion form a dihedral angle of 6.47 (11)°.
of (I)
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3. Supramolecular features
The acesulfamate anions are linked to the 2-amino-3-hydroxypyridinium cations by strong N—H⋯N and N—H⋯O hydrogen bonds, forming centrosymmetric aggregates each consisting of two cations and two anions (Table 2, Fig. 2). These aggregates are linked into a three-dimensional structure by weak O—H⋯O hydrogen bonds involving the sulfonyl groups and by C—H⋯O contacts (Table 2, Fig. 3). The shortest intercentroid separation in (I) is only 4.1798 (15) Å, and thus the π-stacking interactions in this structure are insignificant.
4. Database survey
A search of the Cambridge Structural Database (CSD, version 5.39; Groom et al., 2016) gave 54 hits for the oxathiazin moiety. The compounds most closely related to (I) are 3-carbamoylpyridin-1-ium 6-methyl-2,2,4-trioxo-2H,4H-1,2,3-oxathiazin-3-ide hemihydrate (CIHDEF; Wang et al., 2018), 3-carboxypyridin-1-ium 6-methyl-2,2,4-trioxo-2H,4H-1,2,3-oxathiazin-3-ide (CIHDIJ; Wang et al., 2018), 6-amino-2-oxo-2,3-dihydropyrimidin-1-ium 6-methyl-2,2,4-trioxo-2H,4H-1,2,3-oxathiazin-3-ide 4-aminopyrimidin-2(1H)-one (CIHFEH; Wang et al., 2018), 5-fluoro-2-oxo-2,3-dihydropyrimidin-4(1H)-iminium 6-methyl-4-oxo-4H-1,2,3-oxathiazin-3-ide 2,2-dioxide hemihydrate (GONLIG; Wang et al., 2014), potassium 6-methyl-1,2,3-oxathiazin-4-one-2,2-dioxide (KMOTZD; Paulus 1975), thallium(I) 6-methyl-4-oxo-4H-1,2,3-oxathiazin-3-ide 2,2-dioxide (OCAHUY; Baran et al., 2015), choline acesulfamate (ODIHOZ; Nockemann et al., 2007) and rubidium 6-methyl-4-oxo-4H-1,2,3-oxathiazin-3-ide 2,2-dioxide (SURCIT; Piro et al., 2015). In GONLIG, the molecules are linked by N—H⋯O hydrogen bonds, as in the title compound. In SURCIT, the carbonyl C=O bond distance is 1.231 (5) Å and the sulfoxide S=O bond lengthsare 1.415 (3) and 1.421 (3) Å, which are close toose in the title compound.
5. Hirshfeld surface analysis
In order to visualize the intermolecular interactions in the crystal of (I), Hirshfeld surface analysis (Spackman & Jayatilaka, 2009) was carried out using CrystalExplorer17.5 (Turner et al., 2017). Fig. 4 shows the Hirshfeld surface and the intermolecular contacts of the title compound mapped over dnorm in the range −0.5966 to +1.0568 a.u. The red regions (distances shorter than the sum of the van der Waals radii) are apparent around the oxygen atom O4, which participates in the N—H⋯O contacts, and around the nitrogen atom N1, which participates in the N—H⋯N contacts (Fig. 2, Table 2). The fingerprint plots for (I) are given in Fig. 5. The largest contribution to the overall crystal packing is from O⋯H/H⋯O interactions (43.1%). H⋯H contacts provide another significant contribution to the Hirshfeld surface of 24.2%. The N⋯H/H⋯N contacts appear as a pair of characteristic tips in the fingerprint plots; they contribute 10% to the Hirshfeld surface (Table 2).
6. Synthesis and crystallization
Potassium acesulfamate (1 mmol) was dissolved in 15 mL ethanol and heated to 348 K. To this solution 1 mmol of 2-amino-3-hydroxypyridine in 15 mL of ethanol was added slowly under continuous stirring. After the addition, the solution was stirred for another 6 min at the same temperature. The compound thus formed was separated from the solution and then recrystallized from ethanol solution at room temperature. The red needle-shaped crystals obtained were filtered, washed with ethyl acetate and dried, yield 91%.
7. Refinement
Crystal data, data collection and structure . All C-bound hydrogen atoms were placed in idealized positions and refined isotropically using a riding model, with Uiso(H) = 1.5Ueq(C) for methyl and with Uiso(H) = 1.2Ueq(C) for other C atoms, C—H = 0.96 Å for methyl and 0.93 Å for sp2-hybridized C atoms. All other H atoms were located from the difference map and refined freely.
details are summarized in Table 3
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Supporting information
CCDC reference: 1920140
https://doi.org/10.1107/S2056989020003813/yk2127sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989020003813/yk2127Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S2056989020003813/yk2127Isup3.cml
Data collection: STOE X-AREA (Stoe & Cie, 2002); cell
STOE X-AREA (Stoe & Cie, 2002); data reduction: STOE X-RED (Stoe & Cie, 2002); program(s) used to solve structure: SHELXT2017 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2017 (Sheldrick, 2015b); molecular graphics: PLATON (Spek, 2020); software used to prepare material for publication: WinGX (Farrugia, 2012).C5H7N2O+·C4H4NO4S− | Z = 2 |
Mr = 273.27 | F(000) = 284 |
Triclinic, P1 | Dx = 1.576 Mg m−3 |
a = 7.1676 (5) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 9.1175 (7) Å | Cell parameters from 10423 reflections |
c = 10.1554 (8) Å | θ = 3.0–31.5° |
α = 66.174 (6)° | µ = 0.30 mm−1 |
β = 80.225 (6)° | T = 296 K |
γ = 71.803 (6)° | Prism, red |
V = 576.01 (8) Å3 | 0.57 × 0.42 × 0.21 mm |
STOE IPDS 2 diffractometer | 2263 independent reflections |
Radiation source: sealed X-ray tube, 12 x 0.4 mm long-fine focus | 1951 reflections with I > 2σ(I) |
Detector resolution: 6.67 pixels mm-1 | Rint = 0.031 |
rotation method scans | θmax = 26.0°, θmin = 3.0° |
Absorption correction: integration (X-RED32; Stoe & Cie, 2002) | h = −8→8 |
Tmin = 0.855, Tmax = 0.953 | k = −10→11 |
5116 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)] = 0.040 | Hydrogen site location: mixed |
wR(F2) = 0.114 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.08 | w = 1/[σ2(Fo2) + (0.0615P)2 + 0.1608P] where P = (Fo2 + 2Fc2)/3 |
2263 reflections | (Δ/σ)max = 0.001 |
179 parameters | Δρmax = 0.34 e Å−3 |
0 restraints | Δρmin = −0.26 e Å−3 |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes. |
x | y | z | Uiso*/Ueq | ||
S1 | 1.03944 (7) | 0.17969 (7) | 0.69020 (6) | 0.04075 (18) | |
O1 | 0.9160 (2) | 0.10735 (19) | 0.62259 (17) | 0.0478 (4) | |
O3 | 1.0909 (3) | 0.3136 (2) | 0.57109 (18) | 0.0601 (5) | |
O5 | 0.1101 (3) | 0.5582 (2) | 0.70493 (17) | 0.0553 (4) | |
O4 | 0.5989 (2) | 0.3846 (3) | 0.8548 (2) | 0.0666 (5) | |
N2 | −0.0570 (3) | 0.7569 (2) | 0.9560 (2) | 0.0438 (4) | |
O2 | 1.1970 (2) | 0.0414 (2) | 0.7566 (2) | 0.0659 (5) | |
N3 | 0.2510 (3) | 0.6079 (3) | 0.9066 (2) | 0.0455 (4) | |
N1 | 0.8981 (2) | 0.2371 (2) | 0.80563 (19) | 0.0451 (4) | |
C5 | 0.0626 (3) | 0.6702 (2) | 0.8807 (2) | 0.0371 (4) | |
C3 | 0.7205 (3) | 0.1932 (3) | 0.5985 (2) | 0.0407 (4) | |
C1 | 0.7049 (3) | 0.3113 (3) | 0.7784 (2) | 0.0441 (5) | |
C6 | −0.0206 (3) | 0.6490 (3) | 0.7748 (2) | 0.0435 (5) | |
C2 | 0.6223 (3) | 0.2932 (3) | 0.6663 (2) | 0.0461 (5) | |
H2A | 0.494302 | 0.354995 | 0.641245 | 0.055* | |
C7 | −0.2159 (4) | 0.7151 (3) | 0.7551 (2) | 0.0565 (6) | |
H7 | −0.271871 | 0.700166 | 0.686842 | 0.068* | |
C9 | −0.2527 (3) | 0.8245 (3) | 0.9352 (3) | 0.0564 (6) | |
H9 | −0.330076 | 0.884168 | 0.990109 | 0.068* | |
C8 | −0.3342 (3) | 0.8056 (4) | 0.8363 (3) | 0.0636 (7) | |
H8 | −0.467976 | 0.852033 | 0.821546 | 0.076* | |
C4 | 0.6425 (4) | 0.1525 (4) | 0.4958 (3) | 0.0565 (6) | |
H4A | 0.745607 | 0.076688 | 0.462632 | 0.085* | |
H4B | 0.537932 | 0.101580 | 0.542857 | 0.085* | |
H4C | 0.593203 | 0.252581 | 0.415180 | 0.085* | |
H3A | 0.289 (4) | 0.614 (3) | 0.978 (3) | 0.054 (7)* | |
H3B | 0.320 (4) | 0.547 (3) | 0.867 (3) | 0.053 (7)* | |
H5 | 0.048 (6) | 0.554 (5) | 0.644 (4) | 0.105 (12)* | |
H2 | −0.014 (4) | 0.775 (4) | 1.024 (3) | 0.066 (8)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
S1 | 0.0320 (3) | 0.0515 (3) | 0.0452 (3) | −0.0048 (2) | −0.00460 (19) | −0.0282 (2) |
O1 | 0.0402 (8) | 0.0550 (9) | 0.0611 (9) | −0.0052 (7) | −0.0055 (7) | −0.0393 (8) |
O3 | 0.0616 (10) | 0.0769 (12) | 0.0537 (9) | −0.0322 (9) | 0.0023 (8) | −0.0281 (9) |
O5 | 0.0630 (10) | 0.0730 (11) | 0.0459 (9) | −0.0222 (9) | −0.0056 (8) | −0.0342 (8) |
O4 | 0.0420 (8) | 0.1016 (14) | 0.0750 (11) | 0.0038 (9) | −0.0074 (8) | −0.0674 (11) |
N2 | 0.0387 (9) | 0.0502 (10) | 0.0425 (9) | −0.0055 (8) | −0.0056 (7) | −0.0209 (8) |
O2 | 0.0425 (9) | 0.0720 (12) | 0.0812 (12) | 0.0127 (8) | −0.0196 (8) | −0.0414 (10) |
N3 | 0.0394 (9) | 0.0572 (11) | 0.0463 (10) | −0.0011 (8) | −0.0112 (8) | −0.0312 (9) |
N1 | 0.0343 (8) | 0.0645 (11) | 0.0460 (9) | −0.0050 (8) | −0.0062 (7) | −0.0349 (9) |
C5 | 0.0383 (10) | 0.0395 (10) | 0.0325 (9) | −0.0097 (8) | −0.0047 (7) | −0.0118 (8) |
C3 | 0.0386 (10) | 0.0495 (11) | 0.0404 (10) | −0.0119 (9) | −0.0054 (8) | −0.0218 (9) |
C1 | 0.0363 (10) | 0.0569 (12) | 0.0459 (11) | −0.0052 (9) | −0.0032 (8) | −0.0311 (10) |
C6 | 0.0492 (11) | 0.0508 (12) | 0.0328 (9) | −0.0200 (9) | −0.0067 (8) | −0.0113 (9) |
C2 | 0.0338 (10) | 0.0596 (13) | 0.0481 (11) | −0.0017 (9) | −0.0102 (9) | −0.0283 (10) |
C7 | 0.0522 (13) | 0.0729 (16) | 0.0446 (12) | −0.0244 (12) | −0.0171 (10) | −0.0109 (12) |
C9 | 0.0389 (11) | 0.0605 (14) | 0.0590 (14) | −0.0012 (10) | −0.0020 (10) | −0.0209 (12) |
C8 | 0.0370 (12) | 0.0758 (17) | 0.0612 (15) | −0.0102 (11) | −0.0122 (11) | −0.0089 (13) |
C4 | 0.0589 (14) | 0.0759 (16) | 0.0524 (13) | −0.0233 (12) | −0.0076 (11) | −0.0361 (12) |
S1—O2 | 1.4149 (17) | C5—C6 | 1.417 (3) |
S1—O3 | 1.4235 (18) | C3—C2 | 1.320 (3) |
S1—N1 | 1.5605 (17) | C3—C4 | 1.476 (3) |
S1—O1 | 1.6204 (15) | C1—C2 | 1.454 (3) |
O1—C3 | 1.383 (2) | C6—C7 | 1.354 (3) |
O5—C6 | 1.353 (3) | C2—H2A | 0.9300 |
O5—H5 | 0.84 (4) | C7—C8 | 1.398 (4) |
O4—C1 | 1.236 (3) | C7—H7 | 0.9300 |
N2—C5 | 1.336 (3) | C9—C8 | 1.336 (4) |
N2—C9 | 1.359 (3) | C9—H9 | 0.9300 |
N2—H2 | 0.90 (3) | C8—H8 | 0.9300 |
N3—C5 | 1.317 (3) | C4—H4A | 0.9600 |
N3—H3A | 0.85 (3) | C4—H4B | 0.9600 |
N3—H3B | 0.81 (3) | C4—H4C | 0.9600 |
N1—C1 | 1.359 (3) | ||
O2—S1—O3 | 116.38 (12) | N1—C1—C2 | 119.43 (18) |
O2—S1—N1 | 110.55 (11) | O5—C6—C7 | 126.8 (2) |
O3—S1—N1 | 113.19 (11) | O5—C6—C5 | 113.93 (18) |
O2—S1—O1 | 104.59 (10) | C7—C6—C5 | 119.2 (2) |
O3—S1—O1 | 104.86 (9) | C3—C2—C1 | 123.12 (19) |
N1—S1—O1 | 106.18 (9) | C3—C2—H2A | 118.4 |
C3—O1—S1 | 116.85 (13) | C1—C2—H2A | 118.4 |
C6—O5—H5 | 107 (3) | C6—C7—C8 | 120.7 (2) |
C5—N2—C9 | 123.0 (2) | C6—C7—H7 | 119.7 |
C5—N2—H2 | 122.3 (18) | C8—C7—H7 | 119.7 |
C9—N2—H2 | 114.6 (18) | C8—C9—N2 | 120.2 (2) |
C5—N3—H3A | 117.7 (18) | C8—C9—H9 | 119.9 |
C5—N3—H3B | 118.7 (19) | N2—C9—H9 | 119.9 |
H3A—N3—H3B | 122 (3) | C9—C8—C7 | 119.2 (2) |
C1—N1—S1 | 118.98 (14) | C9—C8—H8 | 120.4 |
N3—C5—N2 | 119.84 (18) | C7—C8—H8 | 120.4 |
N3—C5—C6 | 122.40 (19) | C3—C4—H4A | 109.5 |
N2—C5—C6 | 117.77 (18) | C3—C4—H4B | 109.5 |
C2—C3—O1 | 121.46 (18) | H4A—C4—H4B | 109.5 |
C2—C3—C4 | 126.9 (2) | C3—C4—H4C | 109.5 |
O1—C3—C4 | 111.62 (18) | H4A—C4—H4C | 109.5 |
O4—C1—N1 | 119.67 (18) | H4B—C4—H4C | 109.5 |
O4—C1—C2 | 120.74 (19) | ||
O2—S1—O1—C3 | 156.84 (16) | N2—C5—C6—O5 | −179.25 (18) |
O3—S1—O1—C3 | −80.20 (17) | N3—C5—C6—C7 | 179.3 (2) |
N1—S1—O1—C3 | 39.88 (17) | N2—C5—C6—C7 | −0.6 (3) |
O2—S1—N1—C1 | −151.14 (19) | O1—C3—C2—C1 | −4.9 (4) |
O3—S1—N1—C1 | 76.3 (2) | C4—C3—C2—C1 | 172.6 (2) |
O1—S1—N1—C1 | −38.2 (2) | O4—C1—C2—C3 | −168.2 (2) |
C9—N2—C5—N3 | −179.9 (2) | N1—C1—C2—C3 | 7.4 (4) |
C9—N2—C5—C6 | 0.0 (3) | O5—C6—C7—C8 | 179.5 (2) |
S1—O1—C3—C2 | −20.9 (3) | C5—C6—C7—C8 | 1.0 (4) |
S1—O1—C3—C4 | 161.22 (16) | C5—N2—C9—C8 | 0.2 (4) |
S1—N1—C1—O4 | −166.63 (19) | N2—C9—C8—C7 | 0.2 (4) |
S1—N1—C1—C2 | 17.7 (3) | C6—C7—C8—C9 | −0.8 (4) |
N3—C5—C6—O5 | 0.7 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N3—H3B···O4 | 0.81 (3) | 2.10 (3) | 2.808 (3) | 145 (2) |
N3—H3A···O4i | 0.85 (3) | 2.00 (3) | 2.846 (3) | 175 (3) |
N2—H2···N1i | 0.90 (3) | 1.99 (3) | 2.871 (3) | 168 (3) |
O5—H5···O3ii | 0.84 (4) | 2.50 (4) | 3.090 (2) | 128 (3) |
O5—H5···O3iii | 0.84 (4) | 2.25 (4) | 2.995 (2) | 147 (3) |
C8—H8···O2iv | 0.93 | 2.49 | 3.402 (3) | 166 |
Symmetry codes: (i) −x+1, −y+1, −z+2; (ii) x−1, y, z; (iii) −x+1, −y+1, −z+1; (iv) x−2, y+1, z. |
Funding information
This study was supported by Ondokuz Mayıs University under project No. PYO·FEN.1906.19.001.
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