(1RS,2RS,3RS)-1,2-Dimeth­oxy-3-methyl-2-phenyl-1-(2-thien­yl)cyclo­propane

Torre-Fernández, L.; Suero, M.G.; García-Granda, S.

doi:10.1107/S1600536809009441

organic compounds

CRYSTALLOGRAPHIC
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ISSN: 2056-9890

Volume 65| Part 4| April 2009| Page o810

doi:10.1107/S1600536809009441

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(1RS,2RS,3RS)-1,2-Dimethoxy-3-methyl-2-phenyl-1-(2-thienyl)cyclopropane

Laura Torre-Fernández,^a Marcos G. Suero ^b and Santiago García-Granda ^a ^*

^aDepartamento de Química Física y Analítica, Facultad de Química, Universidad de Oviedo, C/ Julián Clavería, 8, 33006 Oviedo, Spain, and ^bDepartamento de Química Orgánica e Inorgánica, Facultad de Química, Universidad de Oviedo, C/ Julián Clavería, 8, 33006 Oviedo, Spain
^*Correspondence e-mail: sgg@uniovi.es

(Received 5 February 2009; accepted 13 March 2009; online 19 March 2009)

In the title compound, C₁₆H₁₈O₂S, a new cis-1,2-dimethoxycyclopropane, the two methoxy groups are in a cis configuration and in trans positions with respect to the H atom and the phenyl and thienyl rings on the cyclopropyl group. The molecular packing is dominated by weak intermolecular C—H⋯O interactions, allowing the formation of zigzag chains propagating parallel to the c axis. The dihedral angle between the aromatic rings is 86.12 (8)°.

Related literature

For related literature on the chemistry, see: Lebel et al. (2003 ). For a general overview of the biological implications of cyclopropane-related derivatives, see: de Meijere et al. (2003 ). For their occurrence, see: Wessjohann et al. (2003 ).

Experimental

Crystal data

C₁₆H₁₈O₂S
M_r = 274.36
Monoclinic, P 2₁ /c
a = 12.9924 (3) Å
b = 9.7194 (2) Å
c = 14.7960 (3) Å
β = 128.395 (1)°
V = 1464.37 (6) Å³
Z = 4
Cu Kα radiation
μ = 1.92 mm⁻¹
T = 293 K
0.56 × 0.35 × 0.28 mm

Data collection

Oxford Diffraction Nova diffractometer
Absorption correction: refined from ΔF (XABS2; Parkin et al., 1995 ) T_min = 0.330, T_max = 0.581
7070 measured reflections
2830 independent reflections
2435 reflections with I > 2σ(I)
R_int = 0.021

Refinement

R[F² > 2σ(F²)] = 0.055
wR(F²) = 0.192
S = 1.16
2830 reflections
172 parameters
H-atom parameters constrained
Δρ_max = 0.47 e Å⁻³
Δρ_min = −0.52 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C16—H16⋯O2ⁱ	0.93	2.55	3.469 (3)	172
Symmetry code: (i) $[x, -y-{\script{1\over 2}}, z+{\script{1\over 2}}]$ .

Data collection: CrysAlis CCD (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); cell refinement: CrysAlis RED (Oxford Diffraction, 2006 $[Oxford Diffraction (2006). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Abingdon, Oxfordshire, England.]$ ); data reduction: CrysAlis RED; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809009441/cs2110sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809009441/cs2110Isup2.hkl

checkCIF report

Comment top

The cyclopropane ring is a quite common subunit of natural products isolated from plants, fungi, and microorganisms (Wessjohann, et al. 2003). Many of these natural products show biological activity, and some of them have found applications as drugs or insecticides (de Meijere et al., 2003). Classical chemical synthesis of cyclopropane derivatives include the halomethyl-metal mediated cyclopropanation of olefins, the transition-metal-catalyzed carbene-transfer reaction from diazo compounds, and the nucleophilic-addition/ring-closing sequence (Lebel et al. 2003). A new method for the synthesis of cis-1,2-dimethoxycyclopropane through the cyclopropanation of lithium ketone enolates with Fischer carbene complex will be published elsewhere. The molecular structure of the title compound is shown in Fig. 1. There are no unusual bonding features. O atoms of the two methoxy groups are in cis position to each other and in trans positions with the C3 hydrogen atom, and point away from the phenyl and from thienyl rings on the cyclopropyl group, respectively. The molecular packing is dominated by the weak intermolecular interaction C16—H16 ··· O2 allowing the formation of zig-zag chains roughly parallel to the c crystallographic axis and perpendicular to the b axis.

Related literature top

For related literature on the chemistry, see: Lebel et al. (2003). For a general overview of the biological implications of cyclopropane-related derivatives, see: de Meijere et al. (2003). For their occurrence, see: Wessjohann et al. (2003).

Experimental top

Lithium enolate of 2-acetylthiophene was prepared by treatment of a solution of the corresponding ketone (1.2 mmol, 151 mg) and lithium diisopropylamide (1.2 mmol, 0.39 M, 3.1 ml) at 195 K for 30 mins. Pentacarbonyl(1-methoxy-1-phenylmethylene)-chromium (1 mmol, 312 mg) in THF (10 ml) was added over lithium enolate solution at 195 K. Cooling bath was removed and the reaction mixture allowed to warm up to 273 K and stirred for a further 45 mins, concentrated in high vacuum, redisolved in Et₂O (10 ml) and cooled to 195 K. TfOMe (2.0 mmol, 224 µL) was added dropwise to the mixture. After 5 mins, cooling bath was removed and the reaction mixture was stirred for 30 min while allowing the temperature to reach 273 K. The reaction mixture was quenched with NH₄Cl (20 ml). The resulting mixture was diluted with hexanes/ethyl acetate, 10/1 (110 ml) and subjected to air oxidation under sunlight. After 2–12 h the suspension was filtered through Celite and extracted with diethyl ether (3 x 10 ml). The organic layers were combined, dried over anhydrous Na₂SO₄ and concentrated in vacuo. The crude product was purified by flash column chromatography on silica gel (hexanes/ethyl acetate, 20/1) to yield the title compound (277 mg, 77%) as a 1:1 diastereoisomer mixture of the all-S (1,2,3) and all-R forms.

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2006); cell refinement: CrysAlis RED (Oxford Diffraction, 2006); data reduction: CrysAlis RED (Oxford Diffraction, 2006); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

Fig. 1. A view of the title compound with displacement ellipsoids drawn at 50% probability level.

(1RS,2RS,3RS)-1,2-Dimethoxy-3-methyl-2-phenyl-1-(2-thienyl)cyclopropane top

Crystal data top

C₁₆H₁₈O₂S	F(000) = 584
M_r = 274.36	D_x = 1.244 Mg m⁻³
Monoclinic, P2₁/c	Cu Kα radiation, λ = 1.54184 Å
Hall symbol: -P 2ybc	Cell parameters from 5163 reflections
a = 12.9924 (3) Å	θ = 4.3–74.9°
b = 9.7194 (2) Å	µ = 1.92 mm⁻¹
c = 14.7960 (3) Å	T = 293 K
β = 128.395 (1)°	Prism, colourless
V = 1464.37 (6) Å³	0.56 × 0.35 × 0.28 mm
Z = 4

Data collection top

Oxford Diffraction Nova diffractometer	2830 independent reflections
Radiation source: Nova (Cu) X-ray Source	2435 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.021
Detector resolution: 8.2640 pixels mm^-1	θ_max = 75.0°, θ_min = 4.3°
ω scans	h = −15→15
Absorption correction: part of the refinement model (ΔF) (XABS2; Parkin et al., 1995)	k = −12→11
T_min = 0.330, T_max = 0.581	l = −16→18
7070 measured reflections

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)] = 0.055	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.192	H-atom parameters constrained
S = 1.16	w = 1/[σ²(F_o²) + (0.1086P)² + 0.4259P] where P = (F_o² + 2F_c²)/3
2830 reflections	(Δ/σ)_max < 0.001
172 parameters	Δρ_max = 0.47 e Å⁻³
0 restraints	Δρ_min = −0.52 e Å⁻³

Crystal data top

C₁₆H₁₈O₂S	V = 1464.37 (6) Å³
M_r = 274.36	Z = 4
Monoclinic, P2₁/c	Cu Kα radiation
a = 12.9924 (3) Å	µ = 1.92 mm⁻¹
b = 9.7194 (2) Å	T = 293 K
c = 14.7960 (3) Å	0.56 × 0.35 × 0.28 mm
β = 128.395 (1)°

Data collection top

Oxford Diffraction Nova diffractometer	2830 independent reflections
Absorption correction: part of the refinement model (ΔF) (XABS2; Parkin et al., 1995)	2435 reflections with I > 2σ(I)
T_min = 0.330, T_max = 0.581	R_int = 0.021
7070 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.055	0 restraints
wR(F²) = 0.192	H-atom parameters constrained
S = 1.16	Δρ_max = 0.47 e Å⁻³
2830 reflections	Δρ_min = −0.52 e Å⁻³
172 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.

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

	x	y	z	U_iso*/U_eq
S1	0.20782 (8)	−0.21540 (8)	0.43464 (7)	0.0761 (3)
O1	0.21967 (15)	−0.00779 (16)	0.12428 (13)	0.0513 (4)
O2	0.17975 (16)	−0.20993 (15)	0.22182 (15)	0.0549 (4)
C2	0.24847 (18)	−0.0958 (2)	0.29248 (17)	0.0431 (5)
C14	0.2341 (2)	0.0488 (3)	0.43703 (18)	0.0521 (5)
H14	0.2479	0.1376	0.4230	0.063*
C13	0.22814 (19)	−0.0728 (2)	0.37976 (18)	0.0473 (5)
C7	0.2809 (2)	0.1667 (2)	0.26751 (17)	0.0462 (5)
C8	0.3982 (3)	0.2360 (3)	0.3460 (2)	0.0597 (6)
H8	0.4776	0.1894	0.3840	0.072*
C4	0.2883 (3)	0.0554 (3)	0.0888 (2)	0.0654 (7)
H4B	0.2447	0.0343	0.0091	0.098*
H4A	0.3767	0.0211	0.1350	0.098*
H4C	0.2898	0.1533	0.0982	0.098*
C1	0.27813 (19)	0.0184 (2)	0.24060 (17)	0.0435 (5)
C12	0.1637 (2)	0.2390 (3)	0.2108 (2)	0.0566 (6)
H12	0.0844	0.1941	0.1575	0.068*
C3	0.38579 (19)	−0.0804 (2)	0.32878 (19)	0.0499 (5)
H3	0.4492	−0.0403	0.4056	0.060*
C16	0.2013 (3)	−0.1224 (4)	0.5271 (2)	0.0744 (8)
H16	0.1892	−0.1606	0.5775	0.089*
C5	0.4434 (3)	−0.1874 (3)	0.2983 (3)	0.0680 (7)
H5C	0.5304	−0.1603	0.3283	0.102*
H5B	0.3894	−0.1960	0.2160	0.102*
H5A	0.4471	−0.2742	0.3312	0.102*
C6	0.0420 (3)	−0.1869 (3)	0.1399 (2)	0.0707 (7)
H6C	0.0000	−0.2683	0.0944	0.106*
H6A	0.0258	−0.1117	0.0904	0.106*
H6B	0.0073	−0.1650	0.1795	0.106*
C9	0.3975 (3)	0.3743 (3)	0.3681 (3)	0.0770 (8)
H9	0.4764	0.4199	0.4213	0.092*
C15	0.2154 (3)	0.0112 (3)	0.5202 (2)	0.0725 (8)
H15	0.2134	0.0758	0.5654	0.087*
C10	0.2806 (4)	0.4449 (3)	0.3115 (3)	0.0805 (9)
H10	0.2808	0.5378	0.3265	0.097*
C11	0.1640 (3)	0.3783 (3)	0.2333 (3)	0.0722 (7)
H11	0.0851	0.4260	0.1953	0.087*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
S1	0.0953 (6)	0.0630 (5)	0.0924 (6)	0.0042 (3)	0.0694 (5)	0.0161 (3)
O1	0.0570 (8)	0.0570 (9)	0.0485 (8)	−0.0101 (7)	0.0369 (7)	−0.0091 (6)
O2	0.0592 (9)	0.0437 (9)	0.0685 (10)	−0.0084 (6)	0.0430 (8)	−0.0110 (7)
C2	0.0444 (10)	0.0407 (10)	0.0474 (10)	−0.0004 (7)	0.0300 (8)	−0.0020 (8)
C14	0.0751 (14)	0.0535 (12)	0.0511 (11)	0.0033 (10)	0.0508 (11)	0.0016 (9)
C13	0.0455 (10)	0.0502 (12)	0.0485 (11)	0.0042 (8)	0.0304 (9)	0.0057 (8)
C7	0.0570 (11)	0.0442 (11)	0.0512 (10)	−0.0057 (9)	0.0404 (10)	−0.0038 (8)
C8	0.0634 (13)	0.0580 (14)	0.0687 (14)	−0.0138 (11)	0.0464 (12)	−0.0144 (11)
C4	0.0861 (17)	0.0669 (16)	0.0714 (15)	−0.0114 (13)	0.0628 (14)	−0.0076 (12)
C1	0.0441 (10)	0.0458 (11)	0.0454 (10)	−0.0042 (8)	0.0302 (8)	−0.0044 (8)
C12	0.0645 (13)	0.0530 (13)	0.0613 (13)	0.0040 (10)	0.0435 (11)	0.0036 (10)
C3	0.0434 (10)	0.0512 (12)	0.0545 (11)	0.0004 (8)	0.0301 (9)	−0.0065 (9)
C16	0.0739 (16)	0.095 (2)	0.0701 (15)	0.0119 (15)	0.0523 (14)	0.0275 (15)
C5	0.0604 (13)	0.0686 (16)	0.0820 (17)	0.0100 (11)	0.0477 (13)	−0.0076 (13)
C6	0.0588 (14)	0.0811 (18)	0.0701 (15)	−0.0210 (12)	0.0389 (13)	−0.0191 (13)
C9	0.104 (2)	0.0571 (15)	0.0944 (19)	−0.0321 (15)	0.0740 (18)	−0.0298 (14)
C15	0.0888 (18)	0.088 (2)	0.0629 (15)	0.0051 (15)	0.0579 (15)	0.0005 (13)
C10	0.134 (3)	0.0452 (13)	0.106 (2)	−0.0082 (16)	0.096 (2)	−0.0102 (14)
C11	0.099 (2)	0.0547 (15)	0.0890 (18)	0.0175 (14)	0.0713 (17)	0.0124 (13)

Geometric parameters (Å, º) top

S1—C16	1.686 (3)	C1—C3	1.521 (3)
S1—C13	1.708 (2)	C12—C11	1.394 (4)
O1—C1	1.407 (2)	C12—H12	0.9300
O1—C4	1.425 (3)	C3—C5	1.504 (3)
O2—C2	1.400 (2)	C3—H3	0.9800
O2—C6	1.424 (3)	C16—C15	1.324 (5)
C2—C13	1.487 (3)	C16—H16	0.9300
C2—C3	1.518 (3)	C5—H5C	0.9600
C2—C1	1.529 (3)	C5—H5B	0.9600
C14—C13	1.428 (3)	C5—H5A	0.9600
C14—C15	1.441 (3)	C6—H6C	0.9600
C14—H14	0.9300	C6—H6A	0.9600
C7—C8	1.389 (3)	C6—H6B	0.9600
C7—C12	1.389 (3)	C9—C10	1.378 (5)
C7—C1	1.490 (3)	C9—H9	0.9300
C8—C9	1.384 (4)	C15—H15	0.9300
C8—H8	0.9300	C10—C11	1.369 (5)
C4—H4B	0.9600	C10—H10	0.9300
C4—H4A	0.9600	C11—H11	0.9300
C4—H4C	0.9600

C16—S1—C13	92.92 (13)	C11—C12—H12	119.7
C1—O1—C4	112.78 (17)	C5—C3—C2	121.32 (19)
C2—O2—C6	113.11 (18)	C5—C3—C1	122.9 (2)
O2—C2—C13	113.14 (17)	C2—C3—C1	60.40 (13)
O2—C2—C3	113.99 (17)	C5—C3—H3	114.0
C13—C2—C3	118.79 (17)	C2—C3—H3	114.0
O2—C2—C1	116.28 (16)	C1—C3—H3	114.0
C13—C2—C1	124.24 (18)	C15—C16—S1	112.6 (2)
C3—C2—C1	59.91 (13)	C15—C16—H16	123.7
C13—C14—C15	108.7 (2)	S1—C16—H16	123.7
C13—C14—H14	125.6	C3—C5—H5C	109.5
C15—C14—H14	125.6	C3—C5—H5B	109.5
C14—C13—C2	131.81 (19)	H5C—C5—H5B	109.5
C14—C13—S1	110.92 (15)	C3—C5—H5A	109.5
C2—C13—S1	116.98 (16)	H5C—C5—H5A	109.5
C8—C7—C12	118.8 (2)	H5B—C5—H5A	109.5
C8—C7—C1	121.7 (2)	O2—C6—H6C	109.5
C12—C7—C1	119.55 (19)	O2—C6—H6A	109.5
C9—C8—C7	120.3 (3)	H6C—C6—H6A	109.5
C9—C8—H8	119.9	O2—C6—H6B	109.5
C7—C8—H8	119.9	H6C—C6—H6B	109.5
O1—C4—H4B	109.5	H6A—C6—H6B	109.5
O1—C4—H4A	109.5	C10—C9—C8	120.4 (3)
H4B—C4—H4A	109.5	C10—C9—H9	119.8
O1—C4—H4C	109.5	C8—C9—H9	119.8
H4B—C4—H4C	109.5	C16—C15—C14	114.8 (3)
H4A—C4—H4C	109.5	C16—C15—H15	122.6
O1—C1—C7	114.01 (17)	C14—C15—H15	122.6
O1—C1—C3	116.44 (17)	C11—C10—C9	120.1 (3)
C7—C1—C3	121.67 (17)	C11—C10—H10	119.9
O1—C1—C2	111.72 (16)	C9—C10—H10	119.9
C7—C1—C2	122.67 (16)	C10—C11—C12	119.9 (3)
C3—C1—C2	59.69 (13)	C10—C11—H11	120.1
C7—C12—C11	120.6 (2)	C12—C11—H11	120.1
C7—C12—H12	119.7

C6—O2—C2—C13	73.1 (2)	C3—C2—C1—O1	108.80 (19)
C6—O2—C2—C3	−147.1 (2)	O2—C2—C1—C7	145.90 (19)
C6—O2—C2—C1	−80.2 (2)	C13—C2—C1—C7	−4.1 (3)
C15—C14—C13—C2	−175.9 (2)	C3—C2—C1—C7	−110.3 (2)
C15—C14—C13—S1	−2.4 (3)	O2—C2—C1—C3	−103.76 (19)
O2—C2—C13—C14	−153.1 (2)	C13—C2—C1—C3	106.2 (2)
C3—C2—C13—C14	69.2 (3)	C8—C7—C12—C11	−0.6 (3)
C1—C2—C13—C14	−2.2 (3)	C1—C7—C12—C11	−179.0 (2)
O2—C2—C13—S1	33.7 (2)	O2—C2—C3—C5	−5.1 (3)
C3—C2—C13—S1	−103.9 (2)	C13—C2—C3—C5	132.3 (2)
C1—C2—C13—S1	−175.39 (15)	C1—C2—C3—C5	−112.6 (2)
C16—S1—C13—C14	1.88 (18)	O2—C2—C3—C1	107.59 (19)
C16—S1—C13—C2	176.44 (17)	C13—C2—C3—C1	−115.1 (2)
C12—C7—C8—C9	0.8 (3)	O1—C1—C3—C5	9.3 (3)
C1—C7—C8—C9	179.2 (2)	C7—C1—C3—C5	−137.9 (2)
C4—O1—C1—C7	62.3 (2)	C2—C1—C3—C5	110.2 (2)
C4—O1—C1—C3	−87.4 (2)	O1—C1—C3—C2	−100.84 (19)
C4—O1—C1—C2	−153.32 (19)	C7—C1—C3—C2	112.0 (2)
C8—C7—C1—O1	−118.9 (2)	C13—S1—C16—C15	−0.8 (2)
C12—C7—C1—O1	59.4 (2)	C7—C8—C9—C10	−0.7 (4)
C8—C7—C1—C3	29.0 (3)	S1—C16—C15—C14	−0.5 (4)
C12—C7—C1—C3	−152.6 (2)	C13—C14—C15—C16	1.8 (4)
C8—C7—C1—C2	101.0 (2)	C8—C9—C10—C11	0.3 (4)
C12—C7—C1—C2	−80.6 (3)	C9—C10—C11—C12	−0.1 (4)
O2—C2—C1—O1	5.0 (2)	C7—C12—C11—C10	0.3 (4)
C13—C2—C1—O1	−145.00 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C16—H16···O2ⁱ	0.93	2.55	3.469 (3)	172

Symmetry code: (i) x, −y−1/2, z+1/2.

Experimental details

Crystal data
Chemical formula	C₁₆H₁₈O₂S
M_r	274.36
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	12.9924 (3), 9.7194 (2), 14.7960 (3)
β (°)	128.395 (1)
V (Å³)	1464.37 (6)
Z	4
Radiation type	Cu Kα
µ (mm⁻¹)	1.92
Crystal size (mm)	0.56 × 0.35 × 0.28

Data collection
Diffractometer	Oxford Diffraction Nova diffractometer
Absorption correction	Part of the refinement model (ΔF) (XABS2; Parkin et al., 1995)
T_min, T_max	0.330, 0.581
No. of measured, independent and observed [I > 2σ(I)] reflections	7070, 2830, 2435
R_int	0.021
(sin θ/λ)_max (Å⁻¹)	0.626

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.055, 0.192, 1.16
No. of reflections	2830
No. of parameters	172
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.47, −0.52

Computer programs: CrysAlis CCD (Oxford Diffraction, 2006), CrysAlis RED (Oxford Diffraction, 2006), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997), WinGX (Farrugia, 1999).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C16—H16···O2ⁱ	0.93	2.55	3.469 (3)	172

Symmetry code: (i) x, −y−1/2, z+1/2.

Acknowledgements

Financial support from the Spanish Ministerio de Educacion y Ciencia (MAT2006–01997 and 'Factoría de Cristalización' Consolider Ingenio 2010) and FEDER funding is acknowledged.

References

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