6-Hy­droxy-7,8-dimethyl­chroman-2-one

Goswami, S.K.; Hanton, L.R.; McAdam, C.J.; Moratti, S.C.; Simpson, J.

doi:10.1107/S1600536812029704

organic compounds

CRYSTALLOGRAPHIC
COMMUNICATIONS

ISSN: 2056-9890

Volume 68| Part 8| August 2012| Pages o2332-o2333

https://doi.org/10.1107/S1600536812029704

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6-Hydroxy-7,8-dimethylchroman-2-one

Shailesh K. Goswami,^a Lyall R. Hanton,^a C. John McAdam,^a Stephen C. Moratti ^a and Jim Simpson ^a ^*

^aDepartment of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand
^*Correspondence e-mail: jsimpson@alkali.otago.ac.nz

(Received 26 June 2012; accepted 29 June 2012; online 4 July 2012)

The title compound, C₁₁H₁₂O₃, is essentially planar, with an r.m.s. deviation of 0.179 Å from the mean plane through the 14 non-H atoms in the molecule. The benzene ring and the pyranone mean plane are inclined at 13.12 (6)° to one another and the pyranone ring adopts a flattened chair conformation. In the crystal, O—H⋯O hydrogen bonds and C—H⋯O contacts form R₁²(6) rings and link molecules into chains along b. Additional C—H⋯O contacts generate inversion dimers, with R₂²(8) ring motifs, and form sheets parallel to (-102) which are linked by C—H⋯π interactions.

Related literature

For the synthesis, see: Lecea et al. (2010 ). For details of the Cambridge Structural Database, see: Allen (2002 ) and for related structures, see: Cameron et al. (2011 ); Goswami et al. (2011 , 2012 ). For standard bond lengths, see: Allen et al. (1987 ) and for hydrogen-bond motifs, see: Bernstein et al. (1995 ).

Experimental

Crystal data

C₁₁H₁₂O₃
M_r = 192.21
Triclinic, $[P \overline 1]$
a = 6.2808 (14) Å
b = 8.630 (2) Å
c = 9.389 (2) Å
α = 88.603 (6)°
β = 83.638 (5)°
γ = 69.088 (5)°
V = 472.40 (19) Å³
Z = 2
Mo Kα radiation
μ = 0.10 mm⁻¹
T = 92 K
0.34 × 0.32 × 0.12 mm

Data collection

Bruker APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2011 ) T_min = 0.656, T_max = 0.747
9073 measured reflections
3963 independent reflections
3368 reflections with I > 2σ(I)
R_int = 0.035

Refinement

R[F² > 2σ(F²)] = 0.065
wR(F²) = 0.188
S = 1.11
3963 reflections
132 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.60 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C4–C9 benzene ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O8—H8O⋯O1ⁱ	0.89 (2)	1.89 (2)	2.7788 (15)	175 (2)
C9—H9⋯O1ⁱ	0.95	2.63	3.3371 (16)	132
C2—H2A⋯O1ⁱⁱ	0.99	2.52	3.4626 (16)	159
C3—H3B⋯Cgⁱⁱⁱ	0.99	2.54	3.4771 (15)	157
C61—H61C⋯Cg^iv	0.98	2.79	3.6956 (16)	153
Symmetry codes: (i) x, y-1, z; (ii) -x, -y+2, -z; (iii) -x+1, -y+1, -z; (iv) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2011); cell refinement: APEX2 (Bruker, 2011) and SAINT (Bruker, 2011); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ) and TITAN2000 (Hunter & Simpson, 1999 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and TITAN2000; molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008 ); software used to prepare material for publication: SHELXL97, enCIFer (Allen et al., 2004 ), PLATON (Spek, 2009 ) and publCIF (Westrip, 2010 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536812029704/lh5497sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812029704/lh5497Isup2.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536812029704/lh5497Isup3.cml

checkCIF report

Comment top

Our current research is focused on the preparation of quinone/hydroquinone based monomers for utilization in redox-active polymer gels. Synthesis of such systems is a multi-step process and often passes through a hydropyranone intermediate (Lecea et al., 2010; Cameron et al., 2011; Goswami et al., 2011). The title compound illustrates one such intermediate and was isolated during the synthesis of a trifluoromethyl substituted hydroquinone.

The title compound (I), Fig 1, is almost planar with an r.m.s. deviation of 0.179 Å from the best fit plane through the 14 non-hydrogen atoms in the molecule. The maximum deviation from this plane is 0.5437 (11) Å for C2. This is in keeping with the fact that the pyranone ring adopts a flattened chair conformation with the C2 atom displaced by 0.6004 (17) Å from the plane through C1/O2/C5/C4/C3 which, in turn, has an r.m.s. deviation of 0.076 Å. This is in contrast to the closely related 5,6-dimethyl-1,2,9,10- tetrahydropyrano[3,2-f]chromene-3,8-dione (Goswami et al., 2012), where both the C2 and O2 atoms of the pyranone rings were displaced significantly from the molecular plane in opposite directions. A search of the Cambridge Structural Database (Allen, 2002) revealed only two additional tetrahydropyrano derivatives (Goswami et al., 2011, Cameron et al., 2011). However, removing the restraint on substitution at the 3 and 4 positions of the pyranone ring, reveals the structures of more than 190 chromanone derivatives. The bond distances (Allen et al., 1987) and angles in the molecule are normal and, despite the variation in the pyranone ring conformations, similar to those found in related structures (Goswami et al., 2011, 2012; Cameron et al., 2011).

In the crystal structure, O8—H8O···O1 hydrogen bonds, augmented by non-classical C9—H9···O1 contacts, form R²₁(6) rings (Bernstein et al., 1995) and link molecules into rows along b, Fig 2. C2—H2A···O1 hydrogen bonds form inversion dimers generating R²₂(8) rings, Fig 3, which further connect the molecules into sheets approximately parallel to the (-1, 0, 2) plane, Fig 4. C—H···π contacts are also present linking adjacent molecules above and below the plane of the C4···C9 benzene ring and forming columns approximately orthogonal to the (-1, 0, 2) plane and resulting in a series of stacked layers, Fig 5.

Related literature top

For the synthesis, see: Lecea et al. (2010). For details of the Cambridge Structural Database, see: Allen (2002) and for related structures, see: Cameron et al. (2011); Goswami et al. (2011, 2012). For standard bond lengths, see: Allen et al. (1987) and for hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

The title compound was prepared according to the literature (Lecea et al., 2010) by a Friedel-Crafts type reaction of 2,3-dimethylhydroquinone with acrylic acid. X-ray quality crystals of (I) were grown from CDCl₃.

Structure description top

For the synthesis, see: Lecea et al. (2010). For details of the Cambridge Structural Database, see: Allen (2002) and for related structures, see: Cameron et al. (2011); Goswami et al. (2011, 2012). For standard bond lengths, see: Allen et al. (1987) and for hydrogen-bond motifs, see: Bernstein et al. (1995).

Computing details top

Data collection: APEX2 (Bruker, 2011); cell refinement: APEX2 (Bruker, 2011) and SAINT (Bruker, 2011); data reduction: SAINT (Bruker, 2011); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Figures top

	Fig. 1. The structure of (I) with ellipsoids drawn at the 50% probability level.
	Fig. 2. Rows of molecules along b linked by O—H···O and C—H···O hydrogen bonds drawn as dashed lines.
	Fig. 3. Inversion dimers formed by C—H···O hydrogen bonds drawn as dashed lines.
	Fig. 4. Sheets of molecules in the (-1,0,2) plane. Hydrogen bonds are drawn as dashed lines.
	Fig. 5. Overall packing of (I) showing representative C–H···π contacts as dotted lines. The red spheres represent the centroids of the C4···C9 benzene rings and hydrogen bonds are drawn as dashed lines.

6-Hydroxy-7,8-dimethylchroman-2-one top

Crystal data top

C₁₁H₁₂O₃	Z = 2
M_r = 192.21	F(000) = 204
Triclinic, P1	D_x = 1.351 Mg m⁻³
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 6.2808 (14) Å	Cell parameters from 4269 reflections
b = 8.630 (2) Å	θ = 2.5–35.1°
c = 9.389 (2) Å	µ = 0.10 mm⁻¹
α = 88.603 (6)°	T = 92 K
β = 83.638 (5)°	Triangular plate, yellow
γ = 69.088 (5)°	0.34 × 0.32 × 0.12 mm
V = 472.40 (19) Å³

Data collection top

Bruker APEXII CCD area-detector diffractometer	3963 independent reflections
Radiation source: fine-focus sealed tube	3368 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.035
φ and ω scans	θ_max = 35.1°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2011)	h = −9→9
T_min = 0.656, T_max = 0.747	k = −13→12
9073 measured reflections	l = −14→15

Refinement top

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)] = 0.065	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.188	H atoms treated by a mixture of independent and constrained refinement
S = 1.11	w = 1/[σ²(F_o²) + (0.0874P)² + 0.1584P] where P = (F_o² + 2F_c²)/3
3963 reflections	(Δ/σ)_max < 0.001
132 parameters	Δρ_max = 0.60 e Å⁻³
0 restraints	Δρ_min = −0.28 e Å⁻³

Crystal data top

C₁₁H₁₂O₃	γ = 69.088 (5)°
M_r = 192.21	V = 472.40 (19) Å³
Triclinic, P1	Z = 2
a = 6.2808 (14) Å	Mo Kα radiation
b = 8.630 (2) Å	µ = 0.10 mm⁻¹
c = 9.389 (2) Å	T = 92 K
α = 88.603 (6)°	0.34 × 0.32 × 0.12 mm
β = 83.638 (5)°

Data collection top

Bruker APEXII CCD area-detector diffractometer	3963 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2011)	3368 reflections with I > 2σ(I)
T_min = 0.656, T_max = 0.747	R_int = 0.035
9073 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.065	0 restraints
wR(F²) = 0.188	H atoms treated by a mixture of independent and constrained refinement
S = 1.11	Δρ_max = 0.60 e Å⁻³
3963 reflections	Δρ_min = −0.28 e Å⁻³
132 parameters

Special details top

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.

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

	x	y	z	U_iso*/U_eq
O1	0.26085 (18)	1.00639 (11)	0.13645 (11)	0.0271 (2)
C1	0.2601 (2)	0.86709 (14)	0.15707 (13)	0.0195 (2)
O2	0.44911 (14)	0.75378 (10)	0.20340 (9)	0.01890 (18)
C2	0.0627 (2)	0.81355 (14)	0.13980 (13)	0.0198 (2)
H2A	−0.0395	0.8915	0.0761	0.024*
H2B	−0.0265	0.8178	0.2344	0.024*
C3	0.14248 (19)	0.63811 (13)	0.07686 (12)	0.0175 (2)
H3A	0.0114	0.5993	0.0819	0.021*
H3B	0.2033	0.6378	−0.0251	0.021*
C4	0.32642 (18)	0.52366 (13)	0.15984 (11)	0.01564 (19)
C5	0.46469 (18)	0.58834 (13)	0.22549 (11)	0.01568 (19)
C6	0.63239 (18)	0.49425 (14)	0.31075 (11)	0.0165 (2)
C61	0.7683 (2)	0.57324 (16)	0.38576 (13)	0.0213 (2)
H61A	0.7096	0.6933	0.3707	0.032*
H61B	0.9300	0.5266	0.3468	0.032*
H61C	0.7538	0.5514	0.4886	0.032*
C7	0.66848 (19)	0.32489 (14)	0.32618 (12)	0.0179 (2)
C71	0.8441 (2)	0.21682 (16)	0.41777 (14)	0.0247 (2)
H71A	0.9982	0.1949	0.3685	0.037*
H71B	0.8197	0.1116	0.4349	0.037*
H71C	0.8290	0.2735	0.5096	0.037*
C8	0.53406 (19)	0.25683 (13)	0.25696 (12)	0.0181 (2)
O8	0.57401 (17)	0.09172 (11)	0.27400 (11)	0.0255 (2)
H8O	0.472 (4)	0.070 (3)	0.226 (2)	0.038*
C9	0.36335 (19)	0.35568 (13)	0.17644 (12)	0.0175 (2)
H9	0.2715	0.3080	0.1326	0.021*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O1	0.0341 (5)	0.0165 (4)	0.0344 (5)	−0.0117 (3)	−0.0113 (4)	0.0055 (3)
C1	0.0231 (5)	0.0153 (4)	0.0197 (5)	−0.0058 (4)	−0.0048 (4)	0.0014 (3)
O2	0.0213 (4)	0.0159 (4)	0.0221 (4)	−0.0087 (3)	−0.0064 (3)	0.0024 (3)
C2	0.0190 (5)	0.0157 (4)	0.0241 (5)	−0.0046 (4)	−0.0059 (4)	0.0015 (4)
C3	0.0189 (5)	0.0166 (4)	0.0176 (4)	−0.0060 (4)	−0.0059 (4)	0.0012 (3)
C4	0.0162 (4)	0.0146 (4)	0.0159 (4)	−0.0048 (3)	−0.0028 (3)	−0.0008 (3)
C5	0.0172 (4)	0.0147 (4)	0.0154 (4)	−0.0058 (3)	−0.0028 (3)	0.0008 (3)
C6	0.0148 (4)	0.0193 (5)	0.0147 (4)	−0.0052 (3)	−0.0021 (3)	−0.0003 (3)
C61	0.0191 (5)	0.0271 (6)	0.0200 (5)	−0.0102 (4)	−0.0050 (4)	0.0002 (4)
C7	0.0165 (4)	0.0189 (5)	0.0162 (4)	−0.0036 (4)	−0.0034 (3)	0.0020 (3)
C71	0.0237 (5)	0.0241 (5)	0.0228 (5)	−0.0027 (4)	−0.0087 (4)	0.0046 (4)
C8	0.0191 (5)	0.0145 (4)	0.0194 (5)	−0.0041 (3)	−0.0026 (4)	0.0011 (3)
O8	0.0281 (5)	0.0139 (4)	0.0342 (5)	−0.0052 (3)	−0.0101 (4)	0.0039 (3)
C9	0.0177 (5)	0.0146 (4)	0.0197 (5)	−0.0048 (3)	−0.0038 (4)	−0.0001 (3)

Geometric parameters (Å, º) top

O1—C1	1.2145 (14)	C6—C61	1.5039 (16)
C1—O2	1.3489 (14)	C61—H61A	0.9800
C1—C2	1.4948 (17)	C61—H61B	0.9800
O2—C5	1.4076 (13)	C61—H61C	0.9800
C2—C3	1.5261 (16)	C7—C8	1.4051 (16)
C2—H2A	0.9900	C7—C71	1.5044 (16)
C2—H2B	0.9900	C71—H71A	0.9800
C3—C4	1.5049 (15)	C71—H71B	0.9800
C3—H3A	0.9900	C71—H71C	0.9800
C3—H3B	0.9900	C8—O8	1.3644 (14)
C4—C5	1.3882 (15)	C8—C9	1.3943 (15)
C4—C9	1.3916 (15)	O8—O1ⁱ	2.7788 (15)
C5—C6	1.3979 (15)	O8—H8O	0.89 (2)
C6—C7	1.4032 (16)	C9—H9	0.9500

O1—C1—O2	117.42 (11)	C7—C6—C61	120.86 (10)
O1—C1—C2	124.89 (11)	C6—C61—H61A	109.5
O2—C1—C2	117.65 (10)	C6—C61—H61B	109.5
C1—O2—C5	120.91 (9)	H61A—C61—H61B	109.5
C1—C2—C3	111.78 (9)	C6—C61—H61C	109.5
C1—C2—H2A	109.3	H61A—C61—H61C	109.5
C3—C2—H2A	109.3	H61B—C61—H61C	109.5
C1—C2—H2B	109.3	C6—C7—C8	119.04 (10)
C3—C2—H2B	109.3	C6—C7—C71	121.15 (10)
H2A—C2—H2B	107.9	C8—C7—C71	119.79 (10)
C4—C3—C2	109.49 (9)	C7—C71—H71A	109.5
C4—C3—H3A	109.8	C7—C71—H71B	109.5
C2—C3—H3A	109.8	H71A—C71—H71B	109.5
C4—C3—H3B	109.8	C7—C71—H71C	109.5
C2—C3—H3B	109.8	H71A—C71—H71C	109.5
H3A—C3—H3B	108.2	H71B—C71—H71C	109.5
C5—C4—C9	117.89 (10)	O8—C8—C9	121.51 (10)
C5—C4—C3	118.78 (9)	O8—C8—C7	117.50 (10)
C9—C4—C3	123.32 (10)	C9—C8—C7	120.98 (10)
C4—C5—C6	123.13 (10)	C8—O8—H8O	105.9 (13)
C4—C5—O2	120.75 (9)	C4—C9—C8	120.53 (10)
C6—C5—O2	116.05 (9)	C4—C9—H9	119.7
C5—C6—C7	118.36 (10)	C8—C9—H9	119.7
C5—C6—C61	120.77 (10)

Symmetry code: (i) x, y−1, z.

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C4–C9 benzene ring.

D—H···A	D—H	H···A	D···A	D—H···A
O8—H8O···O1ⁱ	0.89 (2)	1.89 (2)	2.7788 (15)	175 (2)
C9—H9···O1ⁱ	0.95	2.63	3.3371 (16)	132
C2—H2A···O1ⁱⁱ	0.99	2.52	3.4626 (16)	159
C3—H3B···Cgⁱⁱⁱ	0.99	2.54	3.4771 (15)	157
C61—H61C···Cg^iv	0.98	2.79	3.6956 (16)	153

Symmetry codes: (i) x, y−1, z; (ii) −x, −y+2, −z; (iii) −x+1, −y+1, −z; (iv) −x+1, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	C₁₁H₁₂O₃
M_r	192.21
Crystal system, space group	Triclinic, P1
Temperature (K)	92
a, b, c (Å)	6.2808 (14), 8.630 (2), 9.389 (2)
α, β, γ (°)	88.603 (6), 83.638 (5), 69.088 (5)
V (Å³)	472.40 (19)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.10
Crystal size (mm)	0.34 × 0.32 × 0.12

Data collection
Diffractometer	Bruker APEXII CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2011)
T_min, T_max	0.656, 0.747
No. of measured, independent and observed [I > 2σ(I)] reflections	9073, 3963, 3368
R_int	0.035
(sin θ/λ)_max (Å⁻¹)	0.809

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.065, 0.188, 1.11
No. of reflections	3963
No. of parameters	132
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.60, −0.28

Computer programs: APEX2 (Bruker, 2011) and SAINT (Bruker, 2011), SAINT (Bruker, 2011), SHELXS97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999), SHELXL97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008), SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2010).

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C4–C9 benzene ring.

D—H···A	D—H	H···A	D···A	D—H···A
O8—H8O···O1ⁱ	0.89 (2)	1.89 (2)	2.7788 (15)	175 (2)
C9—H9···O1ⁱ	0.95	2.63	3.3371 (16)	132
C2—H2A···O1ⁱⁱ	0.99	2.52	3.4626 (16)	159
C3—H3B···Cgⁱⁱⁱ	0.99	2.54	3.4771 (15)	157
C61—H61C···Cg^iv	0.98	2.79	3.6956 (16)	153

Symmetry codes: (i) x, y−1, z; (ii) −x, −y+2, −z; (iii) −x+1, −y+1, −z; (iv) −x+1, −y+1, −z+1.

Acknowledgements

We thank the New Economy Research Fund (grant No. UOO-X0808) for support of this work and the University of Otago for the purchase of the diffractometer.

References

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Volume 68| Part 8| August 2012| Pages o2332-o2333

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