2-(4H-1,3-Benzoxazin-2-yl)phenol

Fernandes, C.; Horn Jr, A.; Howie, R.A.; Schripsma, J.; Wardell, J.L.; Tiekink, E.R.T.

doi:10.1107/S1600536809047631

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 65| Part 12| December 2009| Pages o3104-o3105

doi:10.1107/S1600536809047631

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2-(4H-1,3-Benzoxazin-2-yl)phenol

Christiane Fernandes,^a Adolfo Horn Jr,^a R. Alan Howie,^b Jan Schripsma,^a James L. Wardell ^c ‡ and Edward R. T. Tiekink ^d ^*

^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

(Received 10 November 2009; accepted 10 November 2009; online 18 November 2009)

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 crystal structure, 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

C₁₄H₁₁NO₂
M_r = 225.24
Monoclinic, P 2/n
a = 14.1148 (8) Å
b = 5.1725 (2) Å
c = 15.8813 (8) Å
β = 115.032 (2)°
V = 1050.57 (9) Å³
Z = 4
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 120 K
0.55 × 0.08 × 0.08 mm

Data collection

Bruker–Nonius 95mm CCD camera on κ-goniostat diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 2003 ) T_min = 0.949, T_max = 0.992
10487 measured reflections
1841 independent reflections
1479 reflections with I > 2σ(I)
R_int = 0.066

Refinement

R[F² > 2σ(F²)] = 0.048
wR(F²) = 0.122
S = 1.07
1841 reflections
158 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.32 e Å⁻³
Δρ_min = −0.32 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

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) $[-x+{\script{3\over 2}}, y+1, -z+{\script{3\over 2}}]$ .

Data collection: COLLECT (Hooft, 1998 ); cell refinement: 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

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809047631/lh2952sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809047631/lh2952Isup2.hkl

checkCIF report

Comment top

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.

Related literature top

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 top

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.

Computing details top

Data collection: COLLECT (Hooft, 1998); cell refinement: 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).

Figures top

	Fig. 1. Reaction products.
	Fig. 2. Molecular structure of (I) showing the intramolecular O–H···N hydrogen bonding (orange dashed lines), the atom-labelling scheme, and displacement ellipsoids at the 50% probability level.
	Fig. 3. Supramolecular chain formation along the b axis mediated by C–H···O contacts (bue dashed lines) in the structure of (I).

2-(4H-1,3-Benzoxazin-2-yl)phenol top

Crystal data top

C₁₄H₁₁NO₂	F(000) = 472
M_r = 225.24	D_x = 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

Data collection top

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	R_int = 0.066
Detector resolution: 9.091 pixels mm^-1	θ_max = 25.0°, θ_min = 3.2°
ϕ and ω scans	h = −16→16
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	k = −6→6
T_min = 0.949, T_max = 0.992	l = −18→18
10487 measured reflections

Refinement top

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(F_o²) + (0.0712P)² + 0.1735P] where P = (F_o² + 2F_c²)/3
S = 1.07	(Δ/σ)_max < 0.001
1841 reflections	Δρ_max = 0.32 e Å⁻³
158 parameters	Δρ_min = −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)

Crystal data top

C₁₄H₁₁NO₂	V = 1050.57 (9) Å³
M_r = 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)°

Data collection top

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)
T_min = 0.949, T_max = 0.992	R_int = 0.066
10487 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.048	1 restraint
wR(F²) = 0.122	H-atom parameters constrained
S = 1.07	Δρ_max = 0.32 e Å⁻³
1841 reflections	Δρ_min = −0.32 e Å⁻³
158 parameters

Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
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*

Atomic displacement parameters (Å²) top

	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)

Geometric parameters (Å, º) top

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)

Hydrogen-bond geometry (Å, º) top

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
M_r	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)
T_min, T_max	0.949, 0.992
No. of measured, independent and observed [I > 2σ(I)] reflections	10487, 1841, 1479
R_int	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
Δρ_max, Δρ_min (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).

Hydrogen-bond geometry (Å, º) top

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).

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