(E)-2-[4-(Trifluoro­meth­oxy)benzyl­idene]indan-1-one

Ali, M.A.; Ismail, R.; Tan, S.C.; Rosli, M.M.; Fun, H.-K.

doi:10.1107/S1600536811028698

organic compounds

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ISSN: 2056-9890

Volume 67| Part 8| August 2011| Page o2147

doi:10.1107/S1600536811028698

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(E)-2-[4-(Trifluoromethoxy)benzylidene]indan-1-one

Mohamed Ashraf Ali,^a Rusli Ismail,^a Soo Choon Tan,^a Mohd Mustaqim Rosli ^b and Hoong-Kun Fun ^b ^*‡

^aInstitute for Research in Molecular Medicine, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, and ^bX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia
^*Correspondence e-mail: hkfun@usm.my

(Received 14 July 2011; accepted 17 July 2011; online 30 July 2011)

In the title compound, C₁₇H₁₁F₃O₂, the dihydroindene ring is approximately planar with a maximum deviation of 0.024 (2) Å and makes a dihedral angle of 3.17 (8) Å with the adjacent benzene ring. In the crystal, molecules are interconnected by C—H⋯O interactions, forming an infinite chain along the c axis.

Related literature

For the biological background to dihydroindeno and heterocyclic derivatives, see: Dinges et al. (2006 ); Garton et al. (2006 ); Lin et al. (1997 ); Hsieh et al. (1998 ); Ko et al. (2003 ). For a related structure, see: Ali et al. (2011 ). For standard bond lengths, see: Allen et al. (1987 ) For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ).

Experimental

Crystal data

C₁₇H₁₁F₃O₂
M_r = 304.26
Monoclinic, P 2₁ /c
a = 15.2216 (4) Å
b = 14.6734 (4) Å
c = 6.1463 (1) Å
β = 95.872 (1)°
V = 1365.59 (6) Å³
Z = 4
Mo Kα radiation
μ = 0.12 mm⁻¹
T = 100 K
0.38 × 0.20 × 0.18 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ) T_min = 0.955, T_max = 0.978
27814 measured reflections
4043 independent reflections
3389 reflections with I > 2σ(I)
R_int = 0.036

Refinement

R[F² > 2σ(F²)] = 0.069
wR(F²) = 0.181
S = 1.11
4043 reflections
199 parameters
H-atom parameters constrained
Δρ_max = 0.87 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1B⋯O1ⁱ	0.99	2.51	3.304 (2)	137
C10—H10A⋯O1ⁱⁱ	0.95	2.45	3.309 (2)	151
Symmetry codes: (i) x, y, z+1; (ii) -x, -y+1, -z-1.

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536811028698/sj5181sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536811028698/sj5181Isup2.hkl

checkCIF report

Comment top

Recently it has been reported that dihydroindeno derivatives represent a novel class of KDR kinase inhibitors (Dinges et al. 2006) with inhibition of both KDR and cKit in the appropriate tumor types. They also have the potential to produce antitumor effects through two distinct mechanisms. Inhibition of cKit should result in direct effects on the tumor cell phenotype, while inhibition of KDR should produce indirect effects via disruption of endothelial cell function (Garton et al. 2006). Some of the heterocyclic derivatives inhibited the release of chemical mediators from mast cells, neutrophils, macrophages, and microglial cells in vitro, and suppressed the oedematous response in vivo (Lin et al. 1997, Hsieh et al. 1998, Ko et al. 2003). Many antitumor drugs have been developed for prostate cancer patients but their intolerable systemic toxicity often limits their clinical use. The title compound contains the dihydroindene unit and its structure is reported here, Fig 1.

All bond lengths (Allen et al., 1987) and angles in (I) are within normal ranges. The dihydroindene ring is planar with a maximum deviation of 0.024 (2)Å and it makes a dihedral angle of 3.17 (8)° with the adjancent benzene ring (Fig. 1). In the crystal, the molecules are interconnected by C—H···O interactions (Table 1) to form infinite chains along the c axis (Fig. 2).

Related literature top

For the biological background to dihydroindeno and heterocyclic derivatives, see: Dinges et al. (2006); Garton et al. (2006); Lin et al. (1997); Hsieh et al. (1998); Ko et al. (2003). For a related structure, see: Ali et al. (2011). For standard bond lengths, see: Allen et al. (1987) For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986).

Experimental top

A mixture of 2,3-dihydro-1H-indene-1-one (0.001 mmol) and 4-trifluoromethoxy benzaldehyde (0.001 mmol) was dissolved in methanol (10 ml) and 30% sodium hydroxide solution (5 ml) was added and stirred for 5 h. After completion of the reaction as evident from TLC, the mixture was poured into crushed ice and then neutralized with Con HCl. The precipitated solid was filtered, washed with water and recrystallized from ethanol to reveal the title compound as light yellow crystals.

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure, showing 50% probability displacement ellipsoids. Hydrogen atoms are shown as spheres of arbitrary radius.
	Fig. 2. The packing of (I) showing infinite chains along c axis. Dashed lines indicate hydrogen bonds. H atoms not involved in the hydrogen bond interactions have been omitted for clarity.

(E)-2-[4-(Trifluoromethoxy)benzylidene]indan-1-one top

Crystal data top

C₁₇H₁₁F₃O₂	F(000) = 624
M_r = 304.26	D_x = 1.480 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 9932 reflections
a = 15.2216 (4) Å	θ = 2.7–30.0°
b = 14.6734 (4) Å	µ = 0.12 mm⁻¹
c = 6.1463 (1) Å	T = 100 K
β = 95.872 (1)°	Block, light-yellow
V = 1365.59 (6) Å³	0.38 × 0.20 × 0.18 mm
Z = 4

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	4043 independent reflections
Radiation source: fine-focus sealed tube	3389 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.036
ϕ and ω scans	θ_max = 30.2°, θ_min = 1.3°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −21→21
T_min = 0.955, T_max = 0.978	k = −19→20
27814 measured reflections	l = −8→8

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)] = 0.069	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.181	H-atom parameters constrained
S = 1.11	w = 1/[σ²(F_o²) + (0.0634P)² + 1.8592P] where P = (F_o² + 2F_c²)/3
4043 reflections	(Δ/σ)_max < 0.001
199 parameters	Δρ_max = 0.87 e Å⁻³
0 restraints	Δρ_min = −0.28 e Å⁻³

Crystal data top

C₁₇H₁₁F₃O₂	V = 1365.59 (6) Å³
M_r = 304.26	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 15.2216 (4) Å	µ = 0.12 mm⁻¹
b = 14.6734 (4) Å	T = 100 K
c = 6.1463 (1) Å	0.38 × 0.20 × 0.18 mm
β = 95.872 (1)°

Data collection top

Bruker SMART APEXII CCD area-detector diffractometer	4043 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2009)	3389 reflections with I > 2σ(I)
T_min = 0.955, T_max = 0.978	R_int = 0.036
27814 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.069	0 restraints
wR(F²) = 0.181	H-atom parameters constrained
S = 1.11	Δρ_max = 0.87 e Å⁻³
4043 reflections	Δρ_min = −0.28 e Å⁻³
199 parameters

Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cryosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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
F1	0.40870 (11)	0.43026 (14)	0.4881 (3)	0.0493 (5)
F2	0.47465 (10)	0.43584 (13)	0.1983 (3)	0.0481 (4)
F3	0.51278 (10)	0.33503 (13)	0.4426 (3)	0.0467 (4)
O1	−0.10593 (11)	0.45341 (11)	−0.4450 (2)	0.0277 (3)
O2	0.38837 (11)	0.31658 (12)	0.2471 (3)	0.0315 (4)
C1	−0.06329 (13)	0.35420 (13)	0.0949 (3)	0.0211 (4)
H1A	−0.0435	0.2906	0.1220	0.025*
H1B	−0.0424	0.3919	0.2234	0.025*
C2	−0.16251 (14)	0.35906 (13)	0.0484 (3)	0.0205 (4)
C3	−0.22701 (14)	0.33207 (14)	0.1806 (3)	0.0245 (4)
H3A	−0.2111	0.3077	0.3224	0.029*
C4	−0.31497 (15)	0.34167 (16)	0.1000 (4)	0.0294 (5)
H4A	−0.3595	0.3233	0.1883	0.035*
C5	−0.33995 (15)	0.37768 (16)	−0.1085 (4)	0.0287 (4)
H5A	−0.4007	0.3834	−0.1596	0.034*
C6	−0.27604 (14)	0.40491 (14)	−0.2400 (3)	0.0244 (4)
H6A	−0.2921	0.4295	−0.3815	0.029*
C7	−0.18764 (13)	0.39517 (13)	−0.1592 (3)	0.0199 (4)
C8	−0.10851 (14)	0.41903 (13)	−0.2650 (3)	0.0217 (4)
C9	−0.02974 (15)	0.39174 (14)	−0.1129 (3)	0.0236 (4)
C10	0.05182 (15)	0.40510 (14)	−0.1712 (3)	0.0238 (4)
H10A	0.0541	0.4300	−0.3132	0.029*
C11	0.13779 (14)	0.38722 (14)	−0.0497 (3)	0.0231 (4)
C12	0.21341 (14)	0.40795 (14)	−0.1522 (3)	0.0229 (4)
H12A	0.2071	0.4368	−0.2913	0.027*
C13	0.29726 (14)	0.38732 (14)	−0.0553 (3)	0.0245 (4)
H13A	0.3481	0.3999	−0.1280	0.029*
C14	0.30495 (14)	0.34785 (14)	0.1510 (3)	0.0231 (4)
C15	0.23247 (14)	0.32961 (14)	0.2623 (3)	0.0232 (4)
H15A	0.2398	0.3041	0.4051	0.028*
C16	0.14908 (14)	0.34919 (14)	0.1619 (3)	0.0247 (4)
H16A	0.0987	0.3368	0.2366	0.030*
C17	0.44420 (15)	0.37880 (19)	0.3410 (4)	0.0334 (5)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
F1	0.0378 (9)	0.0719 (12)	0.0369 (8)	0.0042 (8)	−0.0022 (6)	−0.0208 (8)
F2	0.0344 (8)	0.0604 (11)	0.0489 (9)	−0.0086 (7)	0.0013 (7)	0.0168 (8)
F3	0.0275 (7)	0.0728 (12)	0.0387 (8)	0.0091 (7)	−0.0019 (6)	0.0124 (8)
O1	0.0325 (8)	0.0316 (8)	0.0196 (7)	−0.0001 (6)	0.0050 (6)	0.0053 (6)
O2	0.0285 (8)	0.0346 (9)	0.0309 (8)	0.0073 (7)	0.0000 (6)	0.0027 (6)
C1	0.0264 (10)	0.0186 (9)	0.0186 (8)	−0.0006 (7)	0.0030 (7)	0.0032 (6)
C2	0.0271 (10)	0.0157 (8)	0.0188 (8)	0.0003 (7)	0.0039 (7)	−0.0003 (6)
C3	0.0305 (11)	0.0230 (9)	0.0211 (9)	0.0009 (8)	0.0076 (7)	0.0024 (7)
C4	0.0296 (11)	0.0299 (11)	0.0302 (11)	0.0011 (9)	0.0110 (8)	0.0025 (8)
C5	0.0262 (10)	0.0294 (11)	0.0306 (11)	0.0015 (8)	0.0035 (8)	0.0004 (8)
C6	0.0276 (10)	0.0238 (9)	0.0218 (9)	0.0018 (8)	0.0019 (7)	0.0002 (7)
C7	0.0261 (10)	0.0160 (8)	0.0178 (8)	−0.0006 (7)	0.0042 (7)	−0.0007 (6)
C8	0.0271 (10)	0.0192 (9)	0.0192 (8)	0.0002 (7)	0.0037 (7)	0.0014 (6)
C9	0.0331 (11)	0.0198 (9)	0.0183 (8)	0.0003 (8)	0.0040 (7)	0.0004 (7)
C10	0.0327 (11)	0.0208 (9)	0.0184 (8)	−0.0006 (8)	0.0043 (7)	−0.0009 (7)
C11	0.0285 (10)	0.0216 (9)	0.0194 (9)	−0.0007 (8)	0.0029 (7)	0.0024 (7)
C12	0.0300 (10)	0.0213 (9)	0.0173 (8)	−0.0030 (8)	0.0023 (7)	0.0006 (7)
C13	0.0281 (10)	0.0252 (10)	0.0208 (9)	0.0004 (8)	0.0050 (7)	−0.0010 (7)
C14	0.0271 (10)	0.0201 (9)	0.0214 (9)	0.0029 (7)	−0.0013 (7)	−0.0009 (7)
C15	0.0310 (10)	0.0207 (9)	0.0175 (8)	0.0004 (8)	0.0011 (7)	0.0014 (7)
C16	0.0272 (10)	0.0257 (10)	0.0214 (9)	−0.0010 (8)	0.0036 (7)	0.0057 (7)
C17	0.0248 (11)	0.0483 (14)	0.0268 (10)	0.0028 (10)	0.0014 (8)	0.0033 (9)

Geometric parameters (Å, º) top

F1—C17	1.334 (3)	C6—C7	1.393 (3)
F2—C17	1.330 (3)	C6—H6A	0.9500
F3—C17	1.326 (3)	C7—C8	1.469 (3)
O1—C8	1.220 (2)	C8—C9	1.497 (3)
O2—C17	1.337 (3)	C9—C10	1.341 (3)
O2—C14	1.421 (2)	C10—C11	1.463 (3)
C1—C2	1.510 (3)	C10—H10A	0.9500
C1—C9	1.526 (3)	C11—C12	1.401 (3)
C1—H1A	0.9900	C11—C16	1.409 (3)
C1—H1B	0.9900	C12—C13	1.386 (3)
C2—C3	1.395 (3)	C12—H12A	0.9500
C2—C7	1.398 (3)	C13—C14	1.388 (3)
C3—C4	1.387 (3)	C13—H13A	0.9500
C3—H3A	0.9500	C14—C15	1.382 (3)
C4—C5	1.402 (3)	C15—C16	1.384 (3)
C4—H4A	0.9500	C15—H15A	0.9500
C5—C6	1.386 (3)	C16—H16A	0.9500
C5—H5A	0.9500

C17—O2—C14	117.40 (18)	C10—C9—C1	132.40 (19)
C2—C1—C9	103.78 (16)	C8—C9—C1	107.68 (17)
C2—C1—H1A	111.0	C9—C10—C11	129.92 (19)
C9—C1—H1A	111.0	C9—C10—H10A	115.0
C2—C1—H1B	111.0	C11—C10—H10A	115.0
C9—C1—H1B	111.0	C12—C11—C16	118.21 (19)
H1A—C1—H1B	109.0	C12—C11—C10	117.70 (17)
C3—C2—C7	119.75 (19)	C16—C11—C10	124.08 (19)
C3—C2—C1	128.79 (18)	C13—C12—C11	121.48 (18)
C7—C2—C1	111.46 (17)	C13—C12—H12A	119.3
C4—C3—C2	118.33 (19)	C11—C12—H12A	119.3
C4—C3—H3A	120.8	C12—C13—C14	118.15 (19)
C2—C3—H3A	120.8	C12—C13—H13A	120.9
C3—C4—C5	121.8 (2)	C14—C13—H13A	120.9
C3—C4—H4A	119.1	C15—C14—C13	122.39 (19)
C5—C4—H4A	119.1	C15—C14—O2	117.17 (18)
C6—C5—C4	120.1 (2)	C13—C14—O2	120.18 (19)
C6—C5—H5A	120.0	C14—C15—C16	118.77 (18)
C4—C5—H5A	120.0	C14—C15—H15A	120.6
C5—C6—C7	118.19 (19)	C16—C15—H15A	120.6
C5—C6—H6A	120.9	C15—C16—C11	120.89 (19)
C7—C6—H6A	120.9	C15—C16—H16A	119.6
C6—C7—C2	121.90 (18)	C11—C16—H16A	119.6
C6—C7—C8	128.58 (18)	F3—C17—F2	107.74 (19)
C2—C7—C8	109.52 (17)	F3—C17—F1	108.00 (19)
O1—C8—C7	127.16 (19)	F2—C17—F1	106.5 (2)
O1—C8—C9	125.34 (19)	F3—C17—O2	107.9 (2)
C7—C8—C9	107.49 (16)	F2—C17—O2	113.2 (2)
C10—C9—C8	119.89 (18)	F1—C17—O2	113.3 (2)

C9—C1—C2—C3	178.8 (2)	C2—C1—C9—C10	179.7 (2)
C9—C1—C2—C7	−0.3 (2)	C2—C1—C9—C8	1.8 (2)
C7—C2—C3—C4	0.4 (3)	C8—C9—C10—C11	177.73 (19)
C1—C2—C3—C4	−178.7 (2)	C1—C9—C10—C11	0.1 (4)
C2—C3—C4—C5	−0.2 (3)	C9—C10—C11—C12	179.9 (2)
C3—C4—C5—C6	−0.1 (4)	C9—C10—C11—C16	1.0 (4)
C4—C5—C6—C7	0.1 (3)	C16—C11—C12—C13	3.6 (3)
C5—C6—C7—C2	0.0 (3)	C10—C11—C12—C13	−175.43 (19)
C5—C6—C7—C8	−179.7 (2)	C11—C12—C13—C14	−2.0 (3)
C3—C2—C7—C6	−0.3 (3)	C12—C13—C14—C15	−0.7 (3)
C1—C2—C7—C6	178.95 (18)	C12—C13—C14—O2	173.25 (18)
C3—C2—C7—C8	179.50 (18)	C17—O2—C14—C15	−105.6 (2)
C1—C2—C7—C8	−1.3 (2)	C17—O2—C14—C13	80.1 (3)
C6—C7—C8—O1	1.1 (3)	C13—C14—C15—C16	1.8 (3)
C2—C7—C8—O1	−178.7 (2)	O2—C14—C15—C16	−172.35 (18)
C6—C7—C8—C9	−177.8 (2)	C14—C15—C16—C11	−0.2 (3)
C2—C7—C8—C9	2.4 (2)	C12—C11—C16—C15	−2.4 (3)
O1—C8—C9—C10	0.3 (3)	C10—C11—C16—C15	176.49 (19)
C7—C8—C9—C10	179.24 (18)	C14—O2—C17—F3	172.57 (17)
O1—C8—C9—C1	178.51 (19)	C14—O2—C17—F2	−68.3 (3)
C7—C8—C9—C1	−2.6 (2)	C14—O2—C17—F1	53.1 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1B···O1ⁱ	0.99	2.51	3.304 (2)	137
C10—H10A···O1ⁱⁱ	0.95	2.45	3.309 (2)	151

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

Experimental details

Crystal data
Chemical formula	C₁₇H₁₁F₃O₂
M_r	304.26
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	100
a, b, c (Å)	15.2216 (4), 14.6734 (4), 6.1463 (1)
β (°)	95.872 (1)
V (Å³)	1365.59 (6)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.12
Crystal size (mm)	0.38 × 0.20 × 0.18

Data collection
Diffractometer	Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.955, 0.978
No. of measured, independent and observed [I > 2σ(I)] reflections	27814, 4043, 3389
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.708

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.069, 0.181, 1.11
No. of reflections	4043
No. of parameters	199
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.87, −0.28

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C1—H1B···O1ⁱ	0.99	2.51	3.304 (2)	137
C10—H10A···O1ⁱⁱ	0.95	2.45	3.309 (2)	151

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

Footnotes

‡Thomson Reuters ResearcherID: A-3561-2009.

Acknowledgements

The authors wish to express their thanks to Universiti Sains Malaysia (USM), Penang, Malaysia, for providing research facilities. HKF also thanks USM for the Research University Grant (No. 1001/PFIZIK/811160).

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