organic compounds
2-Ethyl-3-hydroxy-1-isopropyl-4-pyridone
aDepartment of Chemistry, University of Free State, Bloemfontein, 9301, PO Box 339, South Africa
*Correspondence e-mail: schuttem@ufs.ac.za
The title compound, C10H15NO2, crystallized with three molecules in the These three molecules are quite similar except for slight differences in the torsion angles of the substituents on the ring. The isopropyl C—C—N—C torsion angles (towards the carbon next to the ethyl bound carbon), for example, are −150.63 (11), −126.77 (13) and −138.76 (11)° for molecules A, B and C, respectively, and the C—C—C—N torsion angles involving the ethyl C atoms are 102.90 (13), 87.81 (14) and 86.47 (13)°. The main difference between the three molecules lies in the way they are arranged in the solid-state structure. All three molecules form dimers that are connected through strong O—H⋯O hydrogen bonds with R22(10) graph-set motifs. The symmetry of the dimers formed does however differ between molecules. Molecules B connect with each other to form inversion dimers. Molecules A and C, on the other hand, form dimers with local twofold symmetry, but the two molecules are crystallographically distinct. The B and C molecules are linked to themselves and to each other via C—H⋯O hydrogen bonds. This results in the formation of a three-dimensional network structure.
Related literature
For background on this type of ligand system, see: Fassihi et al. (2009); Weinberg (1994); Galanello, 2007); Scott et al. (2008). For similar structures, see: Xiao et al. (1992); Burgess et al. (1993); Hider et al. (1990); Dobbin et al. (1993); Brown et al. (1995).
Experimental
Crystal data
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Refinement
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Data collection: APEX2 (Bruker, 2008); cell SAINT-Plus (Bruker, 2008); data reduction: SAINT-Plus; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: WinGX (Farrugia, 1999).
Supporting information
10.1107/S1600536812044091/zl2508sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536812044091/zl2508Isup2.hkl
Supporting information file. DOI: 10.1107/S1600536812044091/zl2508Isup3.cml
2-Ethyl-3-hydroxy-1-isopropyl-4-pyridinone was prepared from the reflux of 2-ethyl-3-hydroxypyran-4-one (ethyl maltol) (5 g, 0,03568 mol) with 6 equivalents of aqueous isopropylamine (12.65 ml, 0,2141 mol, 99%) in 100 ml of water overnight. The mixture turned dark brown. Decolourizing
was added after refluxing and the mixture was left to stand for 30 min. This was then filtered and the dark brown filtrate was evaporated in vacuo to yield a dark brown solid. Crystallization from cold acetone gave pink crystals of 2-ethyl-3-hydroxy-1-isopropyl-4-pyridinone (Yield - 2.5 g, 0.0138 mol, 50%). NMR (300 MHz)13C: 13.3, 18.5, 23.1, 51.5, 111.9, 133.4, 134.3, 145.2, 169.2. NMR (300 MHz) 1H: 1.11(t), 1.38(d), 2.77(q), 4.48(m), 6.18(d), 7.70(d).Aromatic H atoms were positioned geometrically and allowed to ride on their parent atoms, with Uiso(H) = 1.2Ueq(parent) of the parent atom with a C—H distance of 0.93 Å. The methyl and methene H atoms were placed in geometrically idealized positions and constrained to ride on its parent atoms with Uiso(H) = 1.5Ueq(C) and Uiso(H) = 1.2Ueq(C) and at a distance of 0.96 Å and 0.97 Å respectively. The methine hydrogen atoms were placed in geometrically idealized positions and constrained to ride on its parent atoms with Uiso(H) = 1.2 Ueq(C) and at a distance of 0.98 Å. Hydroxyl H atoms were placed from the
and refined freely. Uiso(H) = 0.04216Ueq(C) for molecule A, Uiso(H) = 0.03874Ueq(C) for molecule B and Uiso(H) = 0.03682Ueq(C) for molecule C.Data collection: APEX2 (Bruker, 2008); cell
SAINT-Plus (Bruker, 2008); data reduction: SAINT-Plus (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg & Putz, 2005); software used to prepare material for publication: WinGX (Farrugia, 1999).Fig. 1. Representation of the title compound, showing the numbering scheme and displacement ellipsoids (50% probability). Hydrogen atoms were omitted for clarity. | |
Fig. 2. Hydrogen interactions (O—H···O) of the title compound in the crystal structure. (Molecule A in blue, molecule B in red and molecule C in purple). | |
Fig. 3. Least square overlay of all the atoms in the three independent molecules (Molecule A in blue, molecule B in red and molecule C in purple). |
C10H15NO2 | F(000) = 2352 |
Mr = 181.23 | Dx = 1.227 Mg m−3 Dm = 1.227 Mg m−3 Dm measured by not measured |
Orthorhombic, Pbca | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ac 2ab | Cell parameters from 9920 reflections |
a = 11.7408 (2) Å | θ = 2.4–28.3° |
b = 13.3554 (2) Å | µ = 0.09 mm−1 |
c = 37.5523 (8) Å | T = 100 K |
V = 5888.32 (18) Å3 | Cuboid, pink |
Z = 24 | 0.43 × 0.32 × 0.16 mm |
Bruker APEXII CCD diffractometer | 5939 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.041 |
ϕ and ω scans | θmax = 28.4°, θmin = 2.1° |
Absorption correction: multi-scan (SADABS; Bruker, 2008) | h = −15→15 |
Tmin = 0.968, Tmax = 0.986 | k = −17→14 |
66795 measured reflections | l = −50→49 |
7343 independent 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)] = 0.041 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.111 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.01 | w = 1/[σ2(Fo2) + (0.0549P)2 + 2.2867P] where P = (Fo2 + 2Fc2)/3 |
7343 reflections | (Δ/σ)max = 0.001 |
373 parameters | Δρmax = 0.31 e Å−3 |
0 restraints | Δρmin = −0.28 e Å−3 |
C10H15NO2 | V = 5888.32 (18) Å3 |
Mr = 181.23 | Z = 24 |
Orthorhombic, Pbca | Mo Kα radiation |
a = 11.7408 (2) Å | µ = 0.09 mm−1 |
b = 13.3554 (2) Å | T = 100 K |
c = 37.5523 (8) Å | 0.43 × 0.32 × 0.16 mm |
Bruker APEXII CCD diffractometer | 7343 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2008) | 5939 reflections with I > 2σ(I) |
Tmin = 0.968, Tmax = 0.986 | Rint = 0.041 |
66795 measured reflections |
R[F2 > 2σ(F2)] = 0.041 | 0 restraints |
wR(F2) = 0.111 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.01 | Δρmax = 0.31 e Å−3 |
7343 reflections | Δρmin = −0.28 e Å−3 |
373 parameters |
Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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 | ||
O1A | 0.91293 (7) | 0.19653 (6) | 0.67343 (2) | 0.01841 (18) | |
O2A | 0.82821 (8) | 0.01809 (6) | 0.64712 (3) | 0.0239 (2) | |
N1A | 0.59980 (8) | 0.18817 (7) | 0.62554 (3) | 0.0163 (2) | |
C1A | 0.66341 (10) | 0.10117 (8) | 0.62811 (3) | 0.0172 (2) | |
C2A | 0.76777 (10) | 0.10457 (8) | 0.64456 (3) | 0.0169 (2) | |
C3A | 0.81506 (10) | 0.19473 (9) | 0.65940 (3) | 0.0154 (2) | |
C4A | 0.74207 (10) | 0.27933 (9) | 0.65694 (3) | 0.0180 (2) | |
H4A | 0.7658 | 0.3411 | 0.667 | 0.022* | |
C5A | 0.63923 (10) | 0.27388 (9) | 0.64048 (3) | 0.0185 (2) | |
H5A | 0.5932 | 0.3323 | 0.6394 | 0.022* | |
C6A | 0.48310 (10) | 0.18759 (9) | 0.60952 (3) | 0.0199 (3) | |
H6A | 0.4814 | 0.1348 | 0.5906 | 0.024* | |
C7A | 0.45372 (11) | 0.28715 (10) | 0.59208 (4) | 0.0229 (3) | |
H7A1 | 0.5154 | 0.3068 | 0.5759 | 0.034* | |
H7A2 | 0.4442 | 0.3385 | 0.6105 | 0.034* | |
H7A3 | 0.3827 | 0.2803 | 0.5786 | 0.034* | |
C8A | 0.39681 (11) | 0.15899 (10) | 0.63795 (4) | 0.0275 (3) | |
H8A1 | 0.4159 | 0.0929 | 0.6476 | 0.041* | |
H8A2 | 0.3205 | 0.157 | 0.6274 | 0.041* | |
H8A3 | 0.3985 | 0.2086 | 0.6572 | 0.041* | |
C9A | 0.62142 (11) | 0.00365 (9) | 0.61273 (4) | 0.0227 (3) | |
H9A1 | 0.5382 | 0.0083 | 0.6088 | 0.027* | |
H9A2 | 0.6351 | −0.0506 | 0.6302 | 0.027* | |
C10A | 0.67925 (13) | −0.02331 (11) | 0.57770 (4) | 0.0336 (3) | |
H10G | 0.6521 | −0.0889 | 0.5696 | 0.05* | |
H10H | 0.7619 | −0.0258 | 0.5812 | 0.05* | |
H10I | 0.661 | 0.0274 | 0.5597 | 0.05* | |
O1B | 0.56596 (7) | 0.03944 (7) | 0.46383 (3) | 0.0233 (2) | |
O2B | 0.59291 (8) | −0.13800 (7) | 0.50044 (3) | 0.0222 (2) | |
N1B | 0.84051 (9) | −0.14085 (8) | 0.44368 (3) | 0.0189 (2) | |
C1B | 0.76037 (10) | −0.16947 (9) | 0.46869 (3) | 0.0175 (2) | |
C2B | 0.66930 (10) | −0.10833 (9) | 0.47560 (3) | 0.0165 (2) | |
C3B | 0.65095 (10) | −0.01527 (9) | 0.45722 (3) | 0.0181 (2) | |
C4B | 0.73506 (12) | 0.00685 (10) | 0.43113 (4) | 0.0240 (3) | |
H4B | 0.7278 | 0.0662 | 0.4174 | 0.029* | |
C5B | 0.82553 (11) | −0.05457 (10) | 0.42527 (4) | 0.0233 (3) | |
H5B | 0.88 | −0.0364 | 0.4077 | 0.028* | |
C6B | 0.94331 (11) | −0.20294 (10) | 0.43529 (4) | 0.0232 (3) | |
H6B | 0.9474 | −0.2587 | 0.453 | 0.028* | |
C7B | 1.05136 (12) | −0.14100 (13) | 0.43862 (5) | 0.0384 (4) | |
H7B1 | 1.0522 | −0.107 | 0.4617 | 0.058* | |
H7B2 | 1.0537 | −0.0911 | 0.4195 | 0.058* | |
H7B3 | 1.1179 | −0.185 | 0.4367 | 0.058* | |
C8B | 0.93117 (13) | −0.24888 (10) | 0.39849 (4) | 0.0284 (3) | |
H8B1 | 0.8596 | −0.2864 | 0.3972 | 0.043* | |
H8B2 | 0.9952 | −0.2942 | 0.394 | 0.043* | |
H8B3 | 0.9309 | −0.1956 | 0.3805 | 0.043* | |
C9B | 0.77378 (11) | −0.26520 (9) | 0.48918 (3) | 0.0232 (3) | |
H9B1 | 0.8115 | −0.3158 | 0.4739 | 0.028* | |
H9B2 | 0.6976 | −0.2912 | 0.4957 | 0.028* | |
C10B | 0.84408 (13) | −0.24934 (12) | 0.52279 (4) | 0.0330 (3) | |
H10D | 0.848 | −0.3121 | 0.5362 | 0.05* | |
H10E | 0.8083 | −0.1976 | 0.5375 | 0.05* | |
H10F | 0.9212 | −0.2281 | 0.5163 | 0.05* | |
O1C | 0.05201 (7) | −0.00440 (6) | 0.65172 (2) | 0.01955 (19) | |
O2C | 0.08600 (7) | 0.12707 (7) | 0.70817 (2) | 0.02100 (19) | |
N1C | 0.33901 (8) | −0.02479 (7) | 0.71342 (3) | 0.0154 (2) | |
C1C | 0.25752 (10) | 0.04654 (8) | 0.72127 (3) | 0.0152 (2) | |
C2C | 0.16221 (10) | 0.05441 (8) | 0.70010 (3) | 0.0156 (2) | |
C3C | 0.14118 (10) | −0.01157 (8) | 0.67065 (3) | 0.0154 (2) | |
C4C | 0.22771 (10) | −0.08416 (9) | 0.66494 (3) | 0.0174 (2) | |
H4C | 0.2196 | −0.1306 | 0.6459 | 0.021* | |
C5C | 0.32200 (10) | −0.08894 (8) | 0.68600 (3) | 0.0176 (2) | |
H5C | 0.3776 | −0.1389 | 0.6813 | 0.021* | |
C6C | 0.44322 (10) | −0.03673 (9) | 0.73602 (3) | 0.0176 (2) | |
H6C | 0.4545 | 0.0272 | 0.7494 | 0.021* | |
C7C | 0.54870 (10) | −0.05396 (10) | 0.71333 (4) | 0.0223 (3) | |
H7C1 | 0.5542 | −0.0013 | 0.6952 | 0.033* | |
H7C2 | 0.5433 | −0.1194 | 0.7016 | 0.033* | |
H7C3 | 0.6166 | −0.0523 | 0.7285 | 0.033* | |
C8C | 0.42321 (11) | −0.11941 (10) | 0.76313 (4) | 0.0242 (3) | |
H8C1 | 0.3555 | −0.1036 | 0.7773 | 0.036* | |
H8C2 | 0.4896 | −0.1248 | 0.7788 | 0.036* | |
H8C3 | 0.4116 | −0.1831 | 0.7507 | 0.036* | |
C9C | 0.27357 (10) | 0.11713 (8) | 0.75202 (3) | 0.0179 (2) | |
H9C1 | 0.3138 | 0.0819 | 0.7715 | 0.021* | |
H9C2 | 0.198 | 0.138 | 0.7611 | 0.021* | |
C10C | 0.34170 (12) | 0.21007 (9) | 0.74141 (4) | 0.0240 (3) | |
H10A | 0.35 | 0.2542 | 0.7621 | 0.036* | |
H10B | 0.3015 | 0.2458 | 0.7224 | 0.036* | |
H10C | 0.4172 | 0.1898 | 0.7329 | 0.036* | |
H2A | 0.9000 (17) | 0.0306 (14) | 0.6530 (5) | 0.042 (5)* | |
H2B | 0.5443 (15) | −0.0896 (14) | 0.5054 (5) | 0.039 (5)* | |
H2C | 0.0328 (15) | 0.1317 (13) | 0.6922 (5) | 0.038 (5)* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1A | 0.0164 (4) | 0.0183 (4) | 0.0205 (4) | 0.0008 (3) | −0.0029 (3) | −0.0013 (3) |
O2A | 0.0166 (5) | 0.0134 (4) | 0.0417 (6) | 0.0027 (3) | −0.0069 (4) | −0.0028 (4) |
N1A | 0.0144 (5) | 0.0142 (4) | 0.0204 (5) | 0.0015 (4) | −0.0019 (4) | −0.0017 (4) |
C1A | 0.0169 (6) | 0.0130 (5) | 0.0217 (6) | 0.0007 (4) | 0.0008 (5) | −0.0010 (4) |
C2A | 0.0166 (6) | 0.0126 (5) | 0.0213 (6) | 0.0012 (4) | 0.0015 (4) | −0.0001 (4) |
C3A | 0.0161 (5) | 0.0161 (5) | 0.0139 (5) | −0.0009 (4) | 0.0021 (4) | 0.0011 (4) |
C4A | 0.0196 (6) | 0.0134 (5) | 0.0211 (6) | −0.0005 (4) | −0.0010 (5) | −0.0026 (4) |
C5A | 0.0201 (6) | 0.0132 (5) | 0.0222 (6) | 0.0019 (4) | −0.0010 (5) | −0.0016 (4) |
C6A | 0.0159 (6) | 0.0187 (5) | 0.0252 (6) | 0.0016 (4) | −0.0053 (5) | −0.0033 (5) |
C7A | 0.0227 (6) | 0.0247 (6) | 0.0213 (6) | 0.0043 (5) | −0.0039 (5) | −0.0004 (5) |
C8A | 0.0183 (6) | 0.0253 (6) | 0.0388 (8) | 0.0002 (5) | 0.0000 (5) | 0.0039 (6) |
C9A | 0.0179 (6) | 0.0147 (5) | 0.0355 (8) | 0.0000 (5) | −0.0037 (5) | −0.0048 (5) |
C10A | 0.0332 (8) | 0.0286 (7) | 0.0391 (8) | −0.0024 (6) | −0.0033 (6) | −0.0161 (6) |
O1B | 0.0207 (4) | 0.0217 (4) | 0.0277 (5) | 0.0048 (4) | 0.0034 (4) | 0.0038 (4) |
O2B | 0.0214 (5) | 0.0177 (4) | 0.0274 (5) | 0.0010 (4) | 0.0071 (4) | 0.0033 (4) |
N1B | 0.0201 (5) | 0.0194 (5) | 0.0173 (5) | 0.0037 (4) | 0.0016 (4) | 0.0005 (4) |
C1B | 0.0196 (6) | 0.0173 (5) | 0.0155 (6) | −0.0006 (4) | −0.0025 (4) | −0.0012 (4) |
C2B | 0.0174 (6) | 0.0170 (5) | 0.0149 (5) | −0.0022 (4) | −0.0014 (4) | −0.0013 (4) |
C3B | 0.0179 (6) | 0.0177 (5) | 0.0188 (6) | 0.0001 (4) | −0.0023 (4) | −0.0011 (5) |
C4B | 0.0273 (7) | 0.0211 (6) | 0.0237 (6) | 0.0041 (5) | 0.0042 (5) | 0.0058 (5) |
C5B | 0.0241 (6) | 0.0243 (6) | 0.0214 (6) | 0.0027 (5) | 0.0053 (5) | 0.0048 (5) |
C6B | 0.0213 (6) | 0.0252 (6) | 0.0232 (6) | 0.0080 (5) | 0.0031 (5) | 0.0017 (5) |
C7B | 0.0227 (7) | 0.0444 (9) | 0.0481 (10) | 0.0044 (6) | −0.0057 (7) | −0.0040 (8) |
C8B | 0.0338 (7) | 0.0235 (6) | 0.0279 (7) | 0.0047 (6) | 0.0084 (6) | −0.0018 (5) |
C9B | 0.0277 (7) | 0.0188 (6) | 0.0232 (6) | 0.0048 (5) | 0.0043 (5) | 0.0032 (5) |
C10B | 0.0335 (8) | 0.0424 (8) | 0.0232 (7) | 0.0129 (7) | 0.0007 (6) | 0.0075 (6) |
O1C | 0.0160 (4) | 0.0235 (4) | 0.0192 (4) | 0.0011 (3) | −0.0028 (3) | −0.0035 (4) |
O2C | 0.0180 (4) | 0.0236 (4) | 0.0214 (5) | 0.0069 (3) | −0.0048 (4) | −0.0068 (4) |
N1C | 0.0144 (5) | 0.0148 (4) | 0.0170 (5) | −0.0002 (4) | −0.0019 (4) | −0.0004 (4) |
C1C | 0.0159 (5) | 0.0139 (5) | 0.0158 (5) | −0.0011 (4) | 0.0010 (4) | 0.0000 (4) |
C2C | 0.0158 (5) | 0.0146 (5) | 0.0164 (6) | 0.0003 (4) | 0.0019 (4) | −0.0004 (4) |
C3C | 0.0154 (5) | 0.0157 (5) | 0.0150 (5) | −0.0025 (4) | 0.0014 (4) | 0.0014 (4) |
C4C | 0.0176 (6) | 0.0161 (5) | 0.0184 (6) | −0.0017 (4) | −0.0004 (4) | −0.0033 (4) |
C5C | 0.0181 (6) | 0.0131 (5) | 0.0217 (6) | 0.0005 (4) | 0.0005 (5) | −0.0023 (4) |
C6C | 0.0152 (6) | 0.0170 (5) | 0.0207 (6) | 0.0007 (4) | −0.0049 (4) | −0.0013 (5) |
C7C | 0.0161 (6) | 0.0259 (6) | 0.0249 (7) | −0.0006 (5) | −0.0023 (5) | 0.0010 (5) |
C8C | 0.0226 (6) | 0.0268 (6) | 0.0231 (7) | 0.0018 (5) | −0.0030 (5) | 0.0051 (5) |
C9C | 0.0192 (6) | 0.0170 (5) | 0.0174 (6) | 0.0009 (4) | −0.0027 (4) | −0.0035 (5) |
C10C | 0.0298 (7) | 0.0171 (6) | 0.0251 (7) | −0.0029 (5) | −0.0051 (5) | −0.0021 (5) |
O1A—C3A | 1.2643 (14) | C6B—C7B | 1.520 (2) |
O2A—C2A | 1.3589 (14) | C6B—H6B | 1 |
O2A—H2A | 0.89 (2) | C7B—H7B1 | 0.98 |
N1A—C5A | 1.3563 (15) | C7B—H7B2 | 0.98 |
N1A—C1A | 1.3846 (15) | C7B—H7B3 | 0.98 |
N1A—C6A | 1.4965 (15) | C8B—H8B1 | 0.98 |
C1A—C2A | 1.3729 (17) | C8B—H8B2 | 0.98 |
C1A—C9A | 1.5077 (16) | C8B—H8B3 | 0.98 |
C2A—C3A | 1.4383 (16) | C9B—C10B | 1.523 (2) |
C3A—C4A | 1.4211 (16) | C9B—H9B1 | 0.99 |
C4A—C5A | 1.3583 (17) | C9B—H9B2 | 0.99 |
C4A—H4A | 0.95 | C10B—H10D | 0.98 |
C5A—H5A | 0.95 | C10B—H10E | 0.98 |
C6A—C8A | 1.5206 (19) | C10B—H10F | 0.98 |
C6A—C7A | 1.5218 (17) | O1C—C3C | 1.2690 (14) |
C6A—H6A | 1 | O2C—C2C | 1.3543 (14) |
C7A—H7A1 | 0.98 | O2C—H2C | 0.869 (18) |
C7A—H7A2 | 0.98 | N1C—C5C | 1.3541 (15) |
C7A—H7A3 | 0.98 | N1C—C1C | 1.3819 (15) |
C8A—H8A1 | 0.98 | N1C—C6C | 1.4977 (14) |
C8A—H8A2 | 0.98 | C1C—C2C | 1.3766 (16) |
C8A—H8A3 | 0.98 | C1C—C9C | 1.5028 (16) |
C9A—C10A | 1.523 (2) | C2C—C3C | 1.4356 (16) |
C9A—H9A1 | 0.99 | C3C—C4C | 1.4205 (16) |
C9A—H9A2 | 0.99 | C4C—C5C | 1.3619 (17) |
C10A—H10G | 0.98 | C4C—H4C | 0.95 |
C10A—H10H | 0.98 | C5C—H5C | 0.95 |
C10A—H10I | 0.98 | C6C—C8C | 1.5203 (18) |
O1B—C3B | 1.2614 (15) | C6C—C7C | 1.5208 (17) |
O2B—C2B | 1.3533 (15) | C6C—H6C | 1 |
O2B—H2B | 0.882 (19) | C7C—H7C1 | 0.98 |
N1B—C5B | 1.3552 (16) | C7C—H7C2 | 0.98 |
N1B—C1B | 1.3834 (16) | C7C—H7C3 | 0.98 |
N1B—C6B | 1.4978 (15) | C8C—H8C1 | 0.98 |
C1B—C2B | 1.3702 (17) | C8C—H8C2 | 0.98 |
C1B—C9B | 1.5003 (17) | C8C—H8C3 | 0.98 |
C2B—C3B | 1.4378 (16) | C9C—C10C | 1.5295 (17) |
C3B—C4B | 1.4221 (18) | C9C—H9C1 | 0.99 |
C4B—C5B | 1.3600 (18) | C9C—H9C2 | 0.99 |
C4B—H4B | 0.95 | C10C—H10A | 0.98 |
C5B—H5B | 0.95 | C10C—H10B | 0.98 |
C6B—C8B | 1.5188 (19) | C10C—H10C | 0.98 |
C2A—O2A—H2A | 110.7 (12) | C6B—C7B—H7B1 | 109.5 |
C5A—N1A—C1A | 119.69 (10) | C6B—C7B—H7B2 | 109.5 |
C5A—N1A—C6A | 118.90 (10) | H7B1—C7B—H7B2 | 109.5 |
C1A—N1A—C6A | 121.16 (10) | C6B—C7B—H7B3 | 109.5 |
C2A—C1A—N1A | 119.01 (10) | H7B1—C7B—H7B3 | 109.5 |
C2A—C1A—C9A | 119.53 (10) | H7B2—C7B—H7B3 | 109.5 |
N1A—C1A—C9A | 121.46 (10) | C6B—C8B—H8B1 | 109.5 |
O2A—C2A—C1A | 118.02 (10) | C6B—C8B—H8B2 | 109.5 |
O2A—C2A—C3A | 118.85 (10) | H8B1—C8B—H8B2 | 109.5 |
C1A—C2A—C3A | 123.13 (10) | C6B—C8B—H8B3 | 109.5 |
O1A—C3A—C4A | 124.05 (11) | H8B1—C8B—H8B3 | 109.5 |
O1A—C3A—C2A | 121.89 (11) | H8B2—C8B—H8B3 | 109.5 |
C4A—C3A—C2A | 114.06 (10) | C1B—C9B—C10B | 111.30 (11) |
C5A—C4A—C3A | 121.53 (11) | C1B—C9B—H9B1 | 109.4 |
C5A—C4A—H4A | 119.2 | C10B—C9B—H9B1 | 109.4 |
C3A—C4A—H4A | 119.2 | C1B—C9B—H9B2 | 109.4 |
N1A—C5A—C4A | 122.47 (11) | C10B—C9B—H9B2 | 109.4 |
N1A—C5A—H5A | 118.8 | H9B1—C9B—H9B2 | 108 |
C4A—C5A—H5A | 118.8 | C9B—C10B—H10D | 109.5 |
N1A—C6A—C8A | 109.20 (10) | C9B—C10B—H10E | 109.5 |
N1A—C6A—C7A | 112.09 (10) | H10D—C10B—H10E | 109.5 |
C8A—C6A—C7A | 111.75 (10) | C9B—C10B—H10F | 109.5 |
N1A—C6A—H6A | 107.9 | H10D—C10B—H10F | 109.5 |
C8A—C6A—H6A | 107.9 | H10E—C10B—H10F | 109.5 |
C7A—C6A—H6A | 107.9 | C2C—O2C—H2C | 111.8 (12) |
C6A—C7A—H7A1 | 109.5 | C5C—N1C—C1C | 119.75 (10) |
C6A—C7A—H7A2 | 109.5 | C5C—N1C—C6C | 118.95 (10) |
H7A1—C7A—H7A2 | 109.5 | C1C—N1C—C6C | 121.20 (9) |
C6A—C7A—H7A3 | 109.5 | C2C—C1C—N1C | 119.49 (10) |
H7A1—C7A—H7A3 | 109.5 | C2C—C1C—C9C | 119.85 (10) |
H7A2—C7A—H7A3 | 109.5 | N1C—C1C—C9C | 120.64 (10) |
C6A—C8A—H8A1 | 109.5 | O2C—C2C—C1C | 117.56 (10) |
C6A—C8A—H8A2 | 109.5 | O2C—C2C—C3C | 119.91 (10) |
H8A1—C8A—H8A2 | 109.5 | C1C—C2C—C3C | 122.53 (10) |
C6A—C8A—H8A3 | 109.5 | O1C—C3C—C4C | 123.85 (11) |
H8A1—C8A—H8A3 | 109.5 | O1C—C3C—C2C | 121.81 (10) |
H8A2—C8A—H8A3 | 109.5 | C4C—C3C—C2C | 114.33 (10) |
C1A—C9A—C10A | 112.91 (11) | C5C—C4C—C3C | 121.72 (11) |
C1A—C9A—H9A1 | 109 | C5C—C4C—H4C | 119.1 |
C10A—C9A—H9A1 | 109 | C3C—C4C—H4C | 119.1 |
C1A—C9A—H9A2 | 109 | N1C—C5C—C4C | 122.11 (11) |
C10A—C9A—H9A2 | 109 | N1C—C5C—H5C | 118.9 |
H9A1—C9A—H9A2 | 107.8 | C4C—C5C—H5C | 118.9 |
C9A—C10A—H10G | 109.5 | N1C—C6C—C8C | 109.31 (10) |
C9A—C10A—H10H | 109.5 | N1C—C6C—C7C | 111.33 (10) |
H10G—C10A—H10H | 109.5 | C8C—C6C—C7C | 113.03 (10) |
C9A—C10A—H10I | 109.5 | N1C—C6C—H6C | 107.6 |
H10G—C10A—H10I | 109.5 | C8C—C6C—H6C | 107.6 |
H10H—C10A—H10I | 109.5 | C7C—C6C—H6C | 107.6 |
C2B—O2B—H2B | 111.2 (12) | C6C—C7C—H7C1 | 109.5 |
C5B—N1B—C1B | 119.54 (10) | C6C—C7C—H7C2 | 109.5 |
C5B—N1B—C6B | 117.91 (10) | H7C1—C7C—H7C2 | 109.5 |
C1B—N1B—C6B | 122.53 (10) | C6C—C7C—H7C3 | 109.5 |
C2B—C1B—N1B | 119.65 (11) | H7C1—C7C—H7C3 | 109.5 |
C2B—C1B—C9B | 119.51 (11) | H7C2—C7C—H7C3 | 109.5 |
N1B—C1B—C9B | 120.81 (11) | C6C—C8C—H8C1 | 109.5 |
O2B—C2B—C1B | 118.24 (11) | C6C—C8C—H8C2 | 109.5 |
O2B—C2B—C3B | 118.99 (10) | H8C1—C8C—H8C2 | 109.5 |
C1B—C2B—C3B | 122.76 (11) | C6C—C8C—H8C3 | 109.5 |
O1B—C3B—C4B | 124.36 (11) | H8C1—C8C—H8C3 | 109.5 |
O1B—C3B—C2B | 121.66 (11) | H8C2—C8C—H8C3 | 109.5 |
C4B—C3B—C2B | 113.97 (11) | C1C—C9C—C10C | 111.99 (10) |
C5B—C4B—C3B | 121.90 (12) | C1C—C9C—H9C1 | 109.2 |
C5B—C4B—H4B | 119 | C10C—C9C—H9C1 | 109.2 |
C3B—C4B—H4B | 119 | C1C—C9C—H9C2 | 109.2 |
N1B—C5B—C4B | 122.12 (12) | C10C—C9C—H9C2 | 109.2 |
N1B—C5B—H5B | 118.9 | H9C1—C9C—H9C2 | 107.9 |
C4B—C5B—H5B | 118.9 | C9C—C10C—H10A | 109.5 |
N1B—C6B—C8B | 109.83 (11) | C9C—C10C—H10B | 109.5 |
N1B—C6B—C7B | 110.73 (11) | H10A—C10C—H10B | 109.5 |
C8B—C6B—C7B | 111.90 (12) | C9C—C10C—H10C | 109.5 |
N1B—C6B—H6B | 108.1 | H10A—C10C—H10C | 109.5 |
C8B—C6B—H6B | 108.1 | H10B—C10C—H10C | 109.5 |
C7B—C6B—H6B | 108.1 | ||
C5A—N1A—C1A—C2A | −2.65 (17) | O1B—C3B—C4B—C5B | 179.55 (13) |
C6A—N1A—C1A—C2A | −176.91 (11) | C2B—C3B—C4B—C5B | −1.61 (19) |
C5A—N1A—C1A—C9A | 178.40 (12) | C1B—N1B—C5B—C4B | 1.62 (19) |
C6A—N1A—C1A—C9A | 4.14 (18) | C6B—N1B—C5B—C4B | −179.73 (12) |
N1A—C1A—C2A—O2A | 179.30 (11) | C3B—C4B—C5B—N1B | 0.6 (2) |
C9A—C1A—C2A—O2A | −1.73 (18) | C5B—N1B—C6B—C8B | −69.46 (15) |
N1A—C1A—C2A—C3A | −0.05 (18) | C1B—N1B—C6B—C8B | 109.15 (13) |
C9A—C1A—C2A—C3A | 178.92 (11) | C5B—N1B—C6B—C7B | 54.63 (16) |
O2A—C2A—C3A—O1A | 2.90 (18) | C1B—N1B—C6B—C7B | −126.77 (13) |
C1A—C2A—C3A—O1A | −177.75 (11) | C2B—C1B—C9B—C10B | −90.30 (14) |
O2A—C2A—C3A—C4A | −176.74 (11) | N1B—C1B—C9B—C10B | 87.84 (14) |
C1A—C2A—C3A—C4A | 2.61 (17) | C5C—N1C—C1C—C2C | −2.87 (16) |
O1A—C3A—C4A—C5A | 177.72 (12) | C6C—N1C—C1C—C2C | −179.21 (10) |
C2A—C3A—C4A—C5A | −2.65 (17) | C5C—N1C—C1C—C9C | 178.76 (11) |
C1A—N1A—C5A—C4A | 2.66 (18) | C6C—N1C—C1C—C9C | 2.42 (16) |
C6A—N1A—C5A—C4A | 177.05 (11) | N1C—C1C—C2C—O2C | −178.26 (10) |
C3A—C4A—C5A—N1A | 0.14 (19) | C9C—C1C—C2C—O2C | 0.12 (16) |
C5A—N1A—C6A—C8A | −89.31 (13) | N1C—C1C—C2C—C3C | 2.50 (17) |
C1A—N1A—C6A—C8A | 84.99 (13) | C9C—C1C—C2C—C3C | −179.13 (11) |
C5A—N1A—C6A—C7A | 35.08 (15) | O2C—C2C—C3C—O1C | −0.37 (17) |
C1A—N1A—C6A—C7A | −150.61 (11) | C1C—C2C—C3C—O1C | 178.86 (11) |
C2A—C1A—C9A—C10A | −76.04 (16) | O2C—C2C—C3C—C4C | 179.80 (10) |
N1A—C1A—C9A—C10A | 102.90 (14) | C1C—C2C—C3C—C4C | −0.97 (16) |
C5B—N1B—C1B—C2B | −2.64 (17) | O1C—C3C—C4C—C5C | −179.98 (11) |
C6B—N1B—C1B—C2B | 178.78 (11) | C2C—C3C—C4C—C5C | −0.15 (17) |
C5B—N1B—C1B—C9B | 179.23 (12) | C1C—N1C—C5C—C4C | 1.82 (17) |
C6B—N1B—C1B—C9B | 0.65 (17) | C6C—N1C—C5C—C4C | 178.24 (11) |
N1B—C1B—C2B—O2B | −179.43 (10) | C3C—C4C—C5C—N1C | −0.29 (18) |
C9B—C1B—C2B—O2B | −1.27 (17) | C5C—N1C—C6C—C8C | −80.72 (13) |
N1B—C1B—C2B—C3B | 1.54 (18) | C1C—N1C—C6C—C8C | 95.65 (12) |
C9B—C1B—C2B—C3B | 179.70 (11) | C5C—N1C—C6C—C7C | 44.86 (14) |
O2B—C2B—C3B—O1B | 0.40 (18) | C1C—N1C—C6C—C7C | −138.77 (11) |
C1B—C2B—C3B—O1B | 179.42 (12) | C2C—C1C—C9C—C10C | −91.88 (13) |
O2B—C2B—C3B—C4B | −178.47 (11) | N1C—C1C—C9C—C10C | 86.48 (13) |
C1B—C2B—C3B—C4B | 0.55 (17) |
D—H···A | D—H | H···A | D···A | D—H···A |
O2A—H2A···O1Ci | 0.89 (2) | 1.85 (2) | 2.6503 (13) | 149.9 (17) |
O2B—H2B···O1Bii | 0.882 (19) | 1.859 (18) | 2.6480 (13) | 147.8 (17) |
O2C—H2C···O1Aiii | 0.869 (18) | 1.796 (18) | 2.5868 (12) | 150.3 (17) |
C5B—H5B···O1Cii | 0.95 | 2.43 | 3.3237 (16) | 156 |
C6C—H6C···O2Civ | 1 | 2.59 | 3.4623 (15) | 146 |
C9B—H9B1···O1Bv | 0.99 | 2.44 | 3.3548 (16) | 153 |
Symmetry codes: (i) x+1, y, z; (ii) −x+1, −y, −z+1; (iii) x−1, y, z; (iv) x+1/2, y, −z+3/2; (v) −x+3/2, y−1/2, z. |
Experimental details
Crystal data | |
Chemical formula | C10H15NO2 |
Mr | 181.23 |
Crystal system, space group | Orthorhombic, Pbca |
Temperature (K) | 100 |
a, b, c (Å) | 11.7408 (2), 13.3554 (2), 37.5523 (8) |
V (Å3) | 5888.32 (18) |
Z | 24 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.43 × 0.32 × 0.16 |
Data collection | |
Diffractometer | Bruker APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2008) |
Tmin, Tmax | 0.968, 0.986 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 66795, 7343, 5939 |
Rint | 0.041 |
(sin θ/λ)max (Å−1) | 0.668 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.041, 0.111, 1.01 |
No. of reflections | 7343 |
No. of parameters | 373 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.31, −0.28 |
Computer programs: APEX2 (Bruker, 2008), SAINT-Plus (Bruker, 2008), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg & Putz, 2005), WinGX (Farrugia, 1999).
D—H···A | D—H | H···A | D···A | D—H···A |
O2A—H2A···O1Ci | 0.89 (2) | 1.85 (2) | 2.6503 (13) | 149.9 (17) |
O2B—H2B···O1Bii | 0.882 (19) | 1.859 (18) | 2.6480 (13) | 147.8 (17) |
O2C—H2C···O1Aiii | 0.869 (18) | 1.796 (18) | 2.5868 (12) | 150.3 (17) |
C5B—H5B···O1Cii | 0.95 | 2.43 | 3.3237 (16) | 156.2 |
C6C—H6C···O2Civ | 1 | 2.59 | 3.4623 (15) | 146 |
C9B—H9B1···O1Bv | 0.99 | 2.44 | 3.3548 (16) | 153.4 |
Symmetry codes: (i) x+1, y, z; (ii) −x+1, −y, −z+1; (iii) x−1, y, z; (iv) x+1/2, y, −z+3/2; (v) −x+3/2, y−1/2, z. |
Acknowledgements
The University of the Free State, the Chemistry Department, the NRF and Sasol Ltd and Inkaba yeAfrica are greatly acknowledged for funding.
References
Brandenburg, K. & Putz, H. (2005). DIAMOND. Crystal Impact GbR, Bonn, Germany. Google Scholar
Brown, S. D., Burgess, J., Fawcett, J., Parsons, S. A., Russell, D. R. & Waltham, E. (1995). Acta Cryst. C51, 1335–1338. CSD CrossRef CAS Web of Science IUCr Journals Google Scholar
Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Burgess, J., Fawcett, J., Patel, M. S. & Russell, D. R. (1993). J. Chem. Res. (S). pp. 50–51. Google Scholar
Dobbin, P. S., Hider, R. C., Hall, A. D., Taylor, P. D., Sarpong, P., Porter, J. B., Xiao, G., Xiao, G. & van der Helm, D. (1993). J. Med. Chem. 36, 2448–2458. CSD CrossRef CAS PubMed Web of Science Google Scholar
Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837–838. CrossRef CAS IUCr Journals Google Scholar
Fassihi, A., Abedi, D., Saghaie, L., Sabet, R., Fazeli, H., Bostaki, G., Deilami, O. & Sadinpour, H. (2009). Eur. J. Med. Chem. 44, 2145–2157. Web of Science CrossRef PubMed CAS Google Scholar
Galanello, R. (2007). Ther. Clin. Risk Manage. 3, 795–805. CAS Google Scholar
Hider, R. C., Taylor, P. D., Walkinshaw, M., Wang, J. L. & van der Helm, D. (1990). J. Chem. Res. (S), pp. 316–317. Google Scholar
Scott, L. E., Page, B. D. G., Patrick, B. O. & Orvig, C. (2008). Dalton Trans. pp. 6364–6367. Web of Science CSD CrossRef Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Weinberg, G. A. (1994). Antimicrob. Agents Chemother. 38, 997–1003. CrossRef CAS PubMed Google Scholar
Xiao, G., van der Helm, D., Hider, R. C. & Dobbin, P. S. (1992). J. Chem. Soc. Dalton Trans. pp. 3265–3271. CSD CrossRef Web of Science Google Scholar
This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
3-Hydroxypyridinones, which are derivatives of 3-hydroxypyranones, are known to have antimicrobial and antimalarial activity (Fassihi et al., 2009 and Weinberg, 1994). In addition to this, these compounds are non-toxic and they are approved for therapeutic use in some parts of the world (Galanello, 2007). Furthermore these organic compounds are metal ion chelators and they are used to prepare prodrugs with antioxidant characteristics and have brain targeting capabilities. These drugs have been suggested for the treatment of Alzheimer's disease and might possibly be more effective than treatments that just isolate metals (Scott et al., 2008).
As part of an ongoing study, O,O'-donor bidentate ligands are obtained by functionalizing commercially available 3-hydroxy-2-methylpyran-4-one (maltol) and 3-hydroxy-2-ethylpyran-4-one (ethyl maltol) to the respective 3-hydroxy-2-methylpyrid-4-one and 3-hydroxy-2-ethylpyrid-4-one derivatives. The funtionalizations are performed in order to obtain an array of different electronic and steric properties imparted on the respective starting materials in order to study these effects. Coordination to copper(II) and designing a catalyst with a suitable support for oxidation and the kinetic study thereof are part of this study.
2-Ethyl-3-hydroxy-1-isopropylpyridinone crystallized in the orthorhombic Pbca space group with three molecules in the asymmetric unit. The average carbonyl distances (C=O) in the three molecules of 1.265 (4) Å are comparable to those of similar molecules that have been reported in the literature (Dobbin et al., 1993, Xiao et al., 1992, Burgess et al., 1993, Hider et al., 1990). These four structures differ only by the substituents on the N1 and C1 atoms and are reported as combinations of methyl and ethyl groups compared to ethyl (C1) and isopropyl (N1) for this structure. A distance of 1.265 (1) Å by Xiao et al. (1992), 1.275 (5) Å by Burgess et al. (1993), 1.271 (1) Å by Hider et al. (1990) and 1.264 (2) Å by Dobbin et al. (1993) have been reported. The three crystallograophically distinct molecules are quite similar, for instance the carbonyl distances for molecules A, B and C are 1.264 (1) Å, 1.261 (2) Å and 1.269 (1) Å respectively with r.m.s. values of 0.6447 Å (for an overlay of the complete molecule A and B), 0.6257 Å (for an overlay of the complete molecule B and C) and 0.1476 Å (for an overlay of the complete molecule A and C). Illustrated in Figure 3 is an overlay of all three molecules. As can be seen, the molecules are distinct by small variations in their torsion angles, C1—N1—C6—C7 and C10—C9—C1—N1. For molecule A, B and C respectively, C1—N1—C6—C7 and C10—C9—C1—N1 are -150.62 (11) °, -126.77 (13) ° and -138.76 (11) ° for the first and 102.90 (13) °, 87.81(154 ° and 86.47 (13) ° for the latter torsion angle. The main difference between the three molecules lies however in the way they are arranged in the solid state structure. All three molecules are forming dimers that are connected through strong O—H···O hydrogen bonds with graph set motifs of R22(10). The symmetry of the dimers formed does however differ between molecules. Molecules B connect with each other to form dimers with exact crystallographic inversion symmetry. Molecules A and C, on the other hand form dimers with local two fold symmetry, but the two molecules are crystallographically distinct within the crystal lattice. Two weaker C—H···O intramolecular hydrogen interactions are formed between the ethyl carbon (C9) and the hydroxyl oxygen (O2) in molecule B and C. Another intramolecular C—H···O interactions is formed between the aromatic carbon C5B and a neighboring molecule's ketone oxygen (O1C). Finally, an intermolecular hydrogen interaction is observed between ethyl carbon C9B and a ketone oxygen (O1B).