organic compounds
2-(4H-1,3-Benzoxazin-2-yl)phenol
aLaboratório de Ciências Químicas, Universidade Estadual do Norte, Fluminense-UENF, 28013-602, Campos dos Goytacazes, RJ, Brazil, bDepartment of Chemistry, University of Aberdeen, Old Aberdeen, AB15 5NY, Scotland, cCentro de Desenvolvimento Tecnológico em Saúde (CDTS), Fundação Oswaldo Cruz (FIOCRUZ), Casa Amarela, Campus de Manguinhos, Av. Brasil 4365, 21040-900, Rio de Janeiro, RJ, Brazil, and dDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
*Correspondence e-mail: edward.tiekink@gmail.com
The title compound, C14H11NO2, features an essentially planar molecule, the r.m.s. deviation for the 17 non-H atoms being 0.035 Å. This conformation is stabilized by an intramolecular O—H⋯N hydrogen bond that results in the formation of an S(6) ring. In the methylene–hydroxy C—H⋯O contacts result in a supramolecular chain aligned along the b axis.
Related literature
For general background to the synthesis, see: Hunter & Sims (1972a,b); Corey, & Kühnle (1997); Larter et al. (1998); Chou et al. (2004); Fernandes et al. (2007). For the reactions of 2-hydroxybenzaldehyde derivatives, see; Kitan et al. (1990); Kanakarajan et al. (1975); Meier et al. (1979); Beer et al. (1948).
Experimental
Crystal data
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Refinement
|
Data collection: COLLECT (Hooft, 1998); cell DENZO (Otwinowski & Minor, 1997) and COLLECT; data reduction: DENZO and COLLECT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2009).
Supporting information
10.1107/S1600536809047631/lh2952sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809047631/lh2952Isup2.hkl
A solution of 2-hydroxybenzaldehyde (3.7 g, 0.03 mol), ammonium chloride (3 g, 0.06 mol) and triethylamine (8.1 ml, 0.06 mol) in MeOH (30 ml) was refluxed for 8 h. The solvent was removed in vacuo, the residue was extracted into CHCl3, washed with water (2 x 1 5 ml), dried over magnesium chloride, and rotary evaporated. The pale coloured residue was recrystallized from EtOH to give colourless crystals. Anal. Calc. for C14H11NO2: C, 74.65; H, 4.92; N, 6.22. Found: C, 74.32; H, 4.80; N, 6.01%. 1H NMR (Me2CO-d6, 400 MHz): δ 13.02 (s, 1H), 7.96 (dd, J = 1.6, 8.0 Hz, 1H), 7.41–7.37 (dt, J = 1.7, 8.0 Hz, 1H), 7.33–7.28 (m, 1H), 7.20–7.14 (m, 3H), 6.91 (m, 2H), 4.82 (s, 2H) p.p.m. 13C NMR (CDCl3, 100 MHz): δ 134.1, 129.4, 128.1, 127.3, 126.3, 119.1, 118.0, 116.6, 44.1 p.p.m.; quaternary-C not detected.
The C-bound H atoms were geometrically placed (C–H = 0.95–0.99 Å) and refined as riding with Uiso(H) = 1.2Ueq(C). The hydroxyl-H was located from a difference map and refined with O–H = 0.840±0.001 Å, and with Uiso(H) = 1.5Ueq(O).
Data collection: COLLECT (Hooft, 1998); cell
DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); data reduction: DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2009).C14H11NO2 | F(000) = 472 |
Mr = 225.24 | Dx = 1.424 Mg m−3 |
Monoclinic, P2/n | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2yac | Cell parameters from 10058 reflections |
a = 14.1148 (8) Å | θ = 2.9–27.5° |
b = 5.1725 (2) Å | µ = 0.10 mm−1 |
c = 15.8813 (8) Å | T = 120 K |
β = 115.032 (2)° | Needle, orange |
V = 1050.57 (9) Å3 | 0.55 × 0.08 × 0.08 mm |
Z = 4 |
Bruker–Nonius 95mm CCD camera on κ-goniostat diffractometer | 1841 independent reflections |
Radiation source: Bruker-Nonius FR591 rotating anode | 1479 reflections with I > 2σ(I) |
10 cm confocal mirrors monochromator | Rint = 0.066 |
Detector resolution: 9.091 pixels mm-1 | θmax = 25.0°, θmin = 3.2° |
ϕ and ω scans | h = −16→16 |
Absorption correction: multi-scan (SADABS; Sheldrick, 2003) | k = −6→6 |
Tmin = 0.949, Tmax = 0.992 | l = −18→18 |
10487 measured reflections |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.048 | H-atom parameters constrained |
wR(F2) = 0.122 | w = 1/[σ2(Fo2) + (0.0712P)2 + 0.1735P] where P = (Fo2 + 2Fc2)/3 |
S = 1.07 | (Δ/σ)max < 0.001 |
1841 reflections | Δρmax = 0.32 e Å−3 |
158 parameters | Δρmin = −0.32 e Å−3 |
1 restraint | Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4 |
Primary atom site location: structure-invariant direct methods | Extinction coefficient: 0.031 (5) |
C14H11NO2 | V = 1050.57 (9) Å3 |
Mr = 225.24 | Z = 4 |
Monoclinic, P2/n | Mo Kα radiation |
a = 14.1148 (8) Å | µ = 0.10 mm−1 |
b = 5.1725 (2) Å | T = 120 K |
c = 15.8813 (8) Å | 0.55 × 0.08 × 0.08 mm |
β = 115.032 (2)° |
Bruker–Nonius 95mm CCD camera on κ-goniostat diffractometer | 1841 independent reflections |
Absorption correction: multi-scan (SADABS; Sheldrick, 2003) | 1479 reflections with I > 2σ(I) |
Tmin = 0.949, Tmax = 0.992 | Rint = 0.066 |
10487 measured reflections |
R[F2 > 2σ(F2)] = 0.048 | 1 restraint |
wR(F2) = 0.122 | H-atom parameters constrained |
S = 1.07 | Δρmax = 0.32 e Å−3 |
1841 reflections | Δρmin = −0.32 e Å−3 |
158 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 | ||
O1 | 0.87956 (9) | −0.1882 (2) | 0.76593 (8) | 0.0294 (3) | |
H1O | 0.8351 | −0.0735 | 0.7382 | 0.044* | |
O2 | 0.84545 (9) | 0.3337 (2) | 0.55121 (7) | 0.0251 (3) | |
N1 | 0.78226 (10) | 0.1846 (2) | 0.65809 (9) | 0.0225 (3) | |
C1 | 0.94605 (12) | −0.1824 (3) | 0.72470 (10) | 0.0224 (4) | |
C2 | 1.02672 (13) | −0.3622 (3) | 0.75286 (11) | 0.0255 (4) | |
H2 | 1.0334 | −0.4852 | 0.7995 | 0.031* | |
C3 | 1.09719 (13) | −0.3631 (3) | 0.71350 (11) | 0.0280 (4) | |
H3 | 1.1518 | −0.4875 | 0.7329 | 0.034* | |
C4 | 1.08874 (13) | −0.1831 (3) | 0.64558 (11) | 0.0285 (4) | |
H4 | 1.1375 | −0.1839 | 0.6188 | 0.034* | |
C5 | 1.00909 (12) | −0.0038 (3) | 0.61741 (11) | 0.0255 (4) | |
H5 | 1.0039 | 0.1199 | 0.5714 | 0.031* | |
C6 | 0.93574 (12) | −0.0004 (3) | 0.65525 (10) | 0.0210 (4) | |
C7 | 0.84764 (12) | 0.1812 (3) | 0.62239 (10) | 0.0214 (4) | |
C8 | 0.76543 (12) | 0.5157 (3) | 0.51535 (10) | 0.0218 (4) | |
C9 | 0.76759 (13) | 0.6767 (3) | 0.44659 (11) | 0.0253 (4) | |
H9 | 0.8216 | 0.6614 | 0.4262 | 0.030* | |
C10 | 0.68991 (13) | 0.8601 (3) | 0.40814 (11) | 0.0271 (4) | |
H10 | 0.6900 | 0.9711 | 0.3605 | 0.033* | |
C11 | 0.61167 (13) | 0.8827 (3) | 0.43898 (11) | 0.0277 (4) | |
H11 | 0.5585 | 1.0094 | 0.4127 | 0.033* | |
C12 | 0.61155 (12) | 0.7197 (3) | 0.50813 (11) | 0.0257 (4) | |
H12 | 0.5580 | 0.7361 | 0.5291 | 0.031* | |
C13 | 0.68845 (12) | 0.5327 (3) | 0.54724 (10) | 0.0222 (4) | |
C14 | 0.69092 (13) | 0.3531 (3) | 0.62239 (11) | 0.0252 (4) | |
H14A | 0.6898 | 0.4570 | 0.6743 | 0.030* | |
H14B | 0.6271 | 0.2450 | 0.5977 | 0.030* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0263 (7) | 0.0350 (7) | 0.0318 (7) | 0.0037 (5) | 0.0169 (6) | 0.0083 (5) |
O2 | 0.0243 (7) | 0.0280 (6) | 0.0264 (6) | 0.0058 (5) | 0.0141 (5) | 0.0068 (4) |
N1 | 0.0196 (7) | 0.0265 (8) | 0.0224 (7) | 0.0004 (5) | 0.0097 (6) | −0.0018 (5) |
C1 | 0.0207 (9) | 0.0248 (8) | 0.0220 (8) | −0.0044 (6) | 0.0093 (7) | −0.0042 (6) |
C2 | 0.0253 (9) | 0.0244 (8) | 0.0241 (8) | −0.0006 (7) | 0.0077 (7) | 0.0015 (6) |
C3 | 0.0234 (9) | 0.0277 (9) | 0.0305 (9) | 0.0036 (7) | 0.0090 (8) | −0.0017 (7) |
C4 | 0.0244 (9) | 0.0330 (10) | 0.0318 (9) | 0.0031 (7) | 0.0157 (8) | −0.0004 (7) |
C5 | 0.0252 (9) | 0.0273 (9) | 0.0260 (8) | −0.0004 (7) | 0.0128 (7) | 0.0008 (6) |
C6 | 0.0182 (8) | 0.0228 (8) | 0.0200 (8) | −0.0023 (6) | 0.0063 (7) | −0.0034 (6) |
C7 | 0.0220 (9) | 0.0216 (8) | 0.0197 (8) | −0.0037 (6) | 0.0079 (7) | −0.0024 (6) |
C8 | 0.0191 (8) | 0.0217 (8) | 0.0219 (8) | −0.0001 (6) | 0.0062 (7) | −0.0029 (6) |
C9 | 0.0240 (9) | 0.0277 (9) | 0.0257 (8) | −0.0027 (7) | 0.0120 (7) | −0.0016 (6) |
C10 | 0.0298 (10) | 0.0250 (9) | 0.0239 (8) | −0.0014 (7) | 0.0088 (7) | 0.0016 (6) |
C11 | 0.0265 (9) | 0.0258 (9) | 0.0265 (9) | 0.0034 (7) | 0.0070 (7) | −0.0011 (6) |
C12 | 0.0222 (9) | 0.0285 (9) | 0.0256 (9) | 0.0011 (7) | 0.0094 (7) | −0.0042 (6) |
C13 | 0.0217 (9) | 0.0242 (8) | 0.0190 (8) | −0.0022 (6) | 0.0069 (7) | −0.0050 (6) |
C14 | 0.0233 (9) | 0.0297 (9) | 0.0257 (8) | 0.0018 (7) | 0.0133 (7) | 0.0000 (6) |
O1—C1 | 1.3530 (19) | C5—H5 | 0.9500 |
O1—H1O | 0.8403 | C6—C7 | 1.467 (2) |
O2—C7 | 1.3680 (18) | C8—C13 | 1.382 (2) |
O2—C8 | 1.3937 (19) | C8—C9 | 1.384 (2) |
N1—C7 | 1.271 (2) | C9—C10 | 1.381 (2) |
N1—C14 | 1.458 (2) | C9—H9 | 0.9500 |
C1—C2 | 1.389 (2) | C10—C11 | 1.390 (2) |
C1—C6 | 1.410 (2) | C10—H10 | 0.9500 |
C2—C3 | 1.381 (2) | C11—C12 | 1.385 (2) |
C2—H2 | 0.9500 | C11—H11 | 0.9500 |
C3—C4 | 1.391 (2) | C12—C13 | 1.389 (2) |
C3—H3 | 0.9500 | C12—H12 | 0.9500 |
C4—C5 | 1.378 (2) | C13—C14 | 1.501 (2) |
C4—H4 | 0.9500 | C14—H14A | 0.9900 |
C5—C6 | 1.400 (2) | C14—H14B | 0.9900 |
C1—O1—H1O | 104.4 | C13—C8—C9 | 122.28 (15) |
C7—O2—C8 | 117.29 (12) | C13—C8—O2 | 121.33 (13) |
C7—N1—C14 | 121.61 (13) | C9—C8—O2 | 116.39 (13) |
O1—C1—C2 | 118.12 (14) | C10—C9—C8 | 118.93 (15) |
O1—C1—C6 | 122.02 (14) | C10—C9—H9 | 120.5 |
C2—C1—C6 | 119.86 (14) | C8—C9—H9 | 120.5 |
C3—C2—C1 | 120.39 (15) | C9—C10—C11 | 120.16 (14) |
C3—C2—H2 | 119.8 | C9—C10—H10 | 119.9 |
C1—C2—H2 | 119.8 | C11—C10—H10 | 119.9 |
C2—C3—C4 | 120.46 (15) | C12—C11—C10 | 119.75 (15) |
C2—C3—H3 | 119.8 | C12—C11—H11 | 120.1 |
C4—C3—H3 | 119.8 | C10—C11—H11 | 120.1 |
C5—C4—C3 | 119.52 (15) | C11—C12—C13 | 121.03 (15) |
C5—C4—H4 | 120.2 | C11—C12—H12 | 119.5 |
C3—C4—H4 | 120.2 | C13—C12—H12 | 119.5 |
C4—C5—C6 | 121.26 (14) | C8—C13—C12 | 117.85 (14) |
C4—C5—H5 | 119.4 | C8—C13—C14 | 119.64 (14) |
C6—C5—H5 | 119.4 | C12—C13—C14 | 122.51 (14) |
C5—C6—C1 | 118.50 (14) | N1—C14—C13 | 113.49 (13) |
C5—C6—C7 | 121.67 (13) | N1—C14—H14A | 108.9 |
C1—C6—C7 | 119.81 (14) | C13—C14—H14A | 108.9 |
N1—C7—O2 | 126.42 (14) | N1—C14—H14B | 108.9 |
N1—C7—C6 | 121.08 (13) | C13—C14—H14B | 108.9 |
O2—C7—C6 | 112.49 (13) | H14A—C14—H14B | 107.7 |
O1—C1—C2—C3 | −179.47 (14) | C1—C6—C7—O2 | −176.25 (13) |
C6—C1—C2—C3 | 0.3 (2) | C7—O2—C8—C13 | −3.2 (2) |
C1—C2—C3—C4 | 0.4 (2) | C7—O2—C8—C9 | 176.88 (13) |
C2—C3—C4—C5 | −0.2 (3) | C13—C8—C9—C10 | −0.3 (2) |
C3—C4—C5—C6 | −0.6 (2) | O2—C8—C9—C10 | 179.67 (13) |
C4—C5—C6—C1 | 1.2 (2) | C8—C9—C10—C11 | 0.5 (2) |
C4—C5—C6—C7 | −176.86 (14) | C9—C10—C11—C12 | −0.3 (2) |
O1—C1—C6—C5 | 178.68 (13) | C10—C11—C12—C13 | −0.2 (2) |
C2—C1—C6—C5 | −1.0 (2) | C9—C8—C13—C12 | −0.2 (2) |
O1—C1—C6—C7 | −3.2 (2) | O2—C8—C13—C12 | 179.85 (13) |
C2—C1—C6—C7 | 177.07 (13) | C9—C8—C13—C14 | −179.68 (14) |
C14—N1—C7—O2 | 2.7 (2) | O2—C8—C13—C14 | 0.4 (2) |
C14—N1—C7—C6 | −176.26 (13) | C11—C12—C13—C8 | 0.4 (2) |
C8—O2—C7—N1 | 1.7 (2) | C11—C12—C13—C14 | 179.89 (15) |
C8—O2—C7—C6 | −179.26 (11) | C7—N1—C14—C13 | −5.1 (2) |
C5—C6—C7—N1 | −179.12 (14) | C8—C13—C14—N1 | 3.6 (2) |
C1—C6—C7—N1 | 2.8 (2) | C12—C13—C14—N1 | −175.88 (13) |
C5—C6—C7—O2 | 1.8 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1O···N1 | 0.84 | 1.78 | 2.5586 (16) | 154 |
C14—H14A···O1i | 0.99 | 2.45 | 3.3551 (19) | 151 |
Symmetry code: (i) −x+3/2, y+1, −z+3/2. |
Experimental details
Crystal data | |
Chemical formula | C14H11NO2 |
Mr | 225.24 |
Crystal system, space group | Monoclinic, P2/n |
Temperature (K) | 120 |
a, b, c (Å) | 14.1148 (8), 5.1725 (2), 15.8813 (8) |
β (°) | 115.032 (2) |
V (Å3) | 1050.57 (9) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.55 × 0.08 × 0.08 |
Data collection | |
Diffractometer | Bruker–Nonius 95mm CCD camera on κ-goniostat diffractometer |
Absorption correction | Multi-scan (SADABS; Sheldrick, 2003) |
Tmin, Tmax | 0.949, 0.992 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 10487, 1841, 1479 |
Rint | 0.066 |
(sin θ/λ)max (Å−1) | 0.595 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.048, 0.122, 1.07 |
No. of reflections | 1841 |
No. of parameters | 158 |
No. of restraints | 1 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 0.32, −0.32 |
Computer programs: , DENZO (Otwinowski & Minor, 1997) and COLLECT (Hooft, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), DIAMOND (Brandenburg, 2006), publCIF (Westrip, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
O1—H1O···N1 | 0.84 | 1.78 | 2.5586 (16) | 154 |
C14—H14A···O1i | 0.99 | 2.45 | 3.3551 (19) | 151 |
Symmetry code: (i) −x+3/2, y+1, −z+3/2. |
Footnotes
‡Additional correspondence author, e-mail: j.wardell@abdn.ac.uk.
Acknowledgements
The use of the EPSRC X-ray crystallographic service at the University of Southampton, England and the valuable assistance of the staff there is gratefully acknowledged. JLW acknowledges support from CAPES (Brazil).
References
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Reactions of various arene-aldehydes, ArCHO, e.g. Ar = Ph, thien-2-yl and pyridin2-yl, with ammonia, under basic conditions, have provided rac-2,4,5-Ar3-4,5-dihydro-1H-imidazoles, 1 (Hunter & Sims, 1972a, b; Corey, & Kühnle, 1997; Larter et al., 1998; Chou et al., 2004), see Fig. 3, either as the kinetic product, the cis-isomer, or the thermodynamic product, the trans-isomer. We reported similar products from these aldehydes using the mixture of NH4Cl and NEt3 as the ammonia source in MeOH (Fernandes et al., 2007). In contrast, we have found that 2-hydroxybenzaldehyde, under these conditions produced (2: R = H).
The reaction of 2-hydroxybenzaldehyde with ammonia had previously been studied as a function of solvent (Kitan et al., 1990). Thus in C6H6, hexane or Et2O, 2-HOC6H4CHNH was formed. In H2O, dioxan, MeOH or EtOH solution 2-HOC6H4CH(NCHC6H4OH-2)2 (3), was the product, while in MeOH with NH4OAc and NH4HCO3, both 3 and 4 were formed. Earlier, it had been reported that 2-hydroxybenzaldehyde, NH4OAc and HOAc in refluxing C6H6 produced 4 (Kanakarajan et al., 1975). Interestingly, (2: R = H) has been shown to arise from the acid-catalysed decomposition of 4, alternatively obtained as the cyclo-condensation product of 2-hydroxybenzaldehyde with HONH2 (Meier et al., 1979).
While the NMR spectra, in particular the two hydrogen singlet in the 1H NMR spectrum, suggested the compound (2: R = H) confirmation from the X-ray structure determination was considered to be of value, particularly since treatment of 6-nitro-2-hydroxybenzaldehyde with NH4OAc in acetic acid had been reported to give 5 (Beer et al., 1948). However, no spectral details had been provided for 5. In the light of our findings, the structure of 5 could be modified to (2: R = NO2). The change from 5 to (2: R = NO2) merely involves a prototropic rearrangement. Herein, the crystal and molecular structure of (I) [= 2: R = H in Fig. 1] is described.
The molecular structure of (I), Fig. 2, is essentially planar with the RMS for the 17 non-hydrogen atoms being 0.035 Å. The maximum deviation is 0.049 (1) Å for the N1 atom. This conformation is stabilized by an intramolecular O–H···N hydrogen bond that completes an S(6) ring synthon. The most prominent interactions in the crystal structure are of the type C–H···O, Table 1, which lead to supramolecular chains along the b direction, Fig. 3.