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ISSN: 2056-9890

2,2,2-Tri­fluoro-N-(4-methyl-2-oxo-2H-chromen-7-yl)acetamide

aKey Laboratory of Natural Resources of Changbai Mountain & Functional Molecules (Yanbian University), Ministry of Eduction, Yanji 133002, People's Republic of China
*Correspondence e-mail: zqcong@ybu.edu.cn

(Received 29 February 2012; accepted 5 March 2012; online 10 March 2012)

In the title mol­ecule, C12H8F3NO3, the trifluoro­methyl group is rotationally disordered over three orientations in a 0.5:0.3:0.2 ratio. In the crystal, N—H⋯O hydrogen bonds link the mol­ecules related by translation into chains along the c axis. The crystal packing exhibits ππ inter­actions between the pyran rings of neighboring mol­ecules [centroid–centroid distance = 3.462 (4) Å] and short C⋯O contacts of 3.149 (4) Å.

Related literature

For applications of coumarin derivatives, see: Li et al. (2012[Li, H. Q., Cai, L. & Chen, Z. (2012). Advances in Chemical Sensors, Coumarin-Derived Flurescent Chemosensors, p. 121. Rijeka, Croatia: Intech.]). For potential applications of the title compound as a fluorescent probe for cyanide, see: Li et al. (2011[Li, H. D., Li, B., Jin, L. Y., Kan, Y. H. & Yin, B. Z. (2011). Tetrahedron, 67, 7348-7353.]).

[Scheme 1]

Experimental

Crystal data
  • C12H8F3NO3

  • Mr = 271.19

  • Triclinic, [P \overline 1]

  • a = 8.4897 (17) Å

  • b = 8.5777 (17) Å

  • c = 9.3677 (19) Å

  • α = 89.36 (3)°

  • β = 68.27 (3)°

  • γ = 65.12 (3)°

  • V = 566.3 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.15 mm−1

  • T = 293 K

  • 0.33 × 0.25 × 0.22 mm

Data collection
  • Rigaku R-AXIS RAPID diffractometer

  • Absorption correction: multi-scan (ABSCOR; Higashi, 1995[Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.]) Tmin = 0.954, Tmax = 0.968

  • 5577 measured reflections

  • 2558 independent reflections

  • 1660 reflections with I > 2σ(I)

  • Rint = 0.025

Refinement
  • R[F2 > 2σ(F2)] = 0.046

  • wR(F2) = 0.143

  • S = 1.01

  • 2558 reflections

  • 227 parameters

  • 84 restraints

  • H-atom parameters constrained

  • Δρmax = 0.32 e Å−3

  • Δρmin = −0.29 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O2i 0.86 2.05 2.8960 (19) 170
Symmetry code: (i) x, y, z-1.

Data collection: RAPID-AUTO (Rigaku, 1998[Rigaku (1998). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan.]); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC and Rigaku, 2002[Rigaku/MSC & Rigaku (2002). CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.]); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Coumarins, with the structure of benzopyrone, have many advantages including high fluorescence quantum yield, large Stokes shift, excellent light stability, and low toxicity. Therefore, coumarin derivatives have been used as fluorescent probes of pH, for detection of nitric oxide, nitroxide, and hydrogen peroxide so far. Moreover, coumarin derivatives have served as good chemosensors of anions including cyanide, fluoride, pyrophosphate, acetate, benzoate, and dihydrogenphosphate as well as various metal ions comprised of Hg (II), Cu(II), Zn(II), Ni(II), Ca(II), Pb(II), Mg(II), Fe(III), Al (III), Cr(III), and Ag(I) (Li et al., 2012). Herein, we report the crystal structure of the title compound (I), a potential fluorescent probe for cyanide (Li et al., 2011).

In (I) (Fig. 1), all bond lengths and angles are normal. Intermolecular N—H···O hydrogen bonds (Table 1) link the molecules related by translation along axis c into chains. The crystal packing exhibits π···π interactions between the pyran rings from the neighboring molecules [centroid-centroid distance of 3.462 (4) Å] and short C···O contacts of 3.149 (4) Å.

Related literature top

For applications of coumarin derivatives, see: Li et al. (2012). For potential applications of the title compound as fluorescent probe for cyanide, see: Li et al. (2011).

Experimental top

A solution of 7-amino-4-methylcoumarin (100 mg, 0.57 mmol) and trifluoroacetic anhydride (360 mg, 1.70 mmol) was stirred in THF (5 ml) at room temperature for 1 h under N2. Then the mixture was concentrated and the solid was recrystallized from THF to give the title compound (113.4 mg), yield 73.3%. Crystals suitable for single-crystal X-ray diffraction were grown by slow evaporation of a mixture of tetrahydrofuran and petroleum (60–90 °C) at room temperature.

Refinement top

C-bound H-atoms were placed in calculated positions (C—H 0.93 and 0.96 Å) and were included in the refinement in the riding model with Uiso(H) = 1.5 or 1.2 Ueq(C). N-bound atom H1 was placed in calculated position with N-H = 0.86 Å and refined with Uiso(H) = 1.2 Ueq(N). Trifluoromethyl group was treated as rotationally disordered over three orientations with the occupancies refined in the initial cycles, but in the final cycle they were fixed to 0.5, 0.3 and 0.2, respectively.

Structure description top

Coumarins, with the structure of benzopyrone, have many advantages including high fluorescence quantum yield, large Stokes shift, excellent light stability, and low toxicity. Therefore, coumarin derivatives have been used as fluorescent probes of pH, for detection of nitric oxide, nitroxide, and hydrogen peroxide so far. Moreover, coumarin derivatives have served as good chemosensors of anions including cyanide, fluoride, pyrophosphate, acetate, benzoate, and dihydrogenphosphate as well as various metal ions comprised of Hg (II), Cu(II), Zn(II), Ni(II), Ca(II), Pb(II), Mg(II), Fe(III), Al (III), Cr(III), and Ag(I) (Li et al., 2012). Herein, we report the crystal structure of the title compound (I), a potential fluorescent probe for cyanide (Li et al., 2011).

In (I) (Fig. 1), all bond lengths and angles are normal. Intermolecular N—H···O hydrogen bonds (Table 1) link the molecules related by translation along axis c into chains. The crystal packing exhibits π···π interactions between the pyran rings from the neighboring molecules [centroid-centroid distance of 3.462 (4) Å] and short C···O contacts of 3.149 (4) Å.

For applications of coumarin derivatives, see: Li et al. (2012). For potential applications of the title compound as fluorescent probe for cyanide, see: Li et al. (2011).

Computing details top

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalStructure (Rigaku/MSC and Rigaku, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. The molecular structure of (I) with the atomic numbering. Displacement ellipsoids are drawn at the 30% probalility level.
2,2,2-Trifluoro-N-(4-methyl-2-oxo-2H-chromen-7-yl)acetamide top
Crystal data top
C12H8F3NO3Z = 2
Mr = 271.19F(000) = 276
Triclinic, P1Dx = 1.590 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.4897 (17) ÅCell parameters from 4341 reflections
b = 8.5777 (17) Åθ = 3.3–27.7°
c = 9.3677 (19) ŵ = 0.15 mm1
α = 89.36 (3)°T = 293 K
β = 68.27 (3)°Block, colourless
γ = 65.12 (3)°0.33 × 0.25 × 0.22 mm
V = 566.3 (2) Å3
Data collection top
Rigaku R-AXIS RAPID
diffractometer
2558 independent reflections
Radiation source: fine-focus sealed tube1660 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.025
ω scansθmax = 27.5°, θmin = 3.3°
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
h = 1011
Tmin = 0.954, Tmax = 0.968k = 911
5577 measured reflectionsl = 1212
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.046Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.143H-atom parameters constrained
S = 1.01 w = 1/[σ2(Fo2) + (0.0898P)2]
where P = (Fo2 + 2Fc2)/3
2558 reflections(Δ/σ)max = 0.043
227 parametersΔρmax = 0.32 e Å3
84 restraintsΔρmin = 0.29 e Å3
Crystal data top
C12H8F3NO3γ = 65.12 (3)°
Mr = 271.19V = 566.3 (2) Å3
Triclinic, P1Z = 2
a = 8.4897 (17) ÅMo Kα radiation
b = 8.5777 (17) ŵ = 0.15 mm1
c = 9.3677 (19) ÅT = 293 K
α = 89.36 (3)°0.33 × 0.25 × 0.22 mm
β = 68.27 (3)°
Data collection top
Rigaku R-AXIS RAPID
diffractometer
2558 independent reflections
Absorption correction: multi-scan
(ABSCOR; Higashi, 1995)
1660 reflections with I > 2σ(I)
Tmin = 0.954, Tmax = 0.968Rint = 0.025
5577 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.04684 restraints
wR(F2) = 0.143H-atom parameters constrained
S = 1.01Δρmax = 0.32 e Å3
2558 reflectionsΔρmin = 0.29 e Å3
227 parameters
Special details top

Experimental. (See detailed section in the paper)

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
xyzUiso*/UeqOcc. (<1)
C10.2553 (3)0.1720 (2)0.69632 (18)0.0411 (4)
C20.2740 (3)0.0012 (2)0.66094 (19)0.0428 (5)
H20.28630.07290.73360.051*
C30.2746 (3)0.0569 (2)0.52793 (19)0.0378 (4)
C40.2947 (4)0.2365 (3)0.4954 (2)0.0558 (6)
H4A0.30230.29430.58270.084*
H4B0.40800.30190.40380.084*
H4C0.18660.22840.47890.084*
C50.2568 (3)0.0591 (2)0.41442 (17)0.0340 (4)
C60.2416 (2)0.2238 (2)0.44841 (17)0.0317 (4)
C70.2285 (3)0.3436 (2)0.34783 (17)0.0345 (4)
H70.21670.45310.37530.041*
C80.2336 (3)0.2953 (2)0.20462 (17)0.0326 (4)
C90.2482 (3)0.1313 (2)0.16628 (18)0.0411 (5)
H90.25040.10010.07060.049*
C100.2595 (3)0.0160 (2)0.26924 (19)0.0406 (4)
H100.26900.09270.24230.049*
C110.2084 (3)0.5682 (2)0.10611 (19)0.0367 (4)
C120.2258 (3)0.6488 (3)0.0436 (2)0.0470 (5)
F10.1414 (13)0.6068 (13)0.1225 (11)0.0525 (18)0.50
F20.1399 (19)0.8175 (10)0.0063 (12)0.065 (3)0.50
F30.4003 (12)0.5937 (15)0.1389 (9)0.068 (3)0.50
F1'0.215 (4)0.570 (3)0.150 (3)0.115 (8)0.30
F2'0.087 (3)0.821 (3)0.016 (2)0.078 (6)0.30
F3'0.383 (2)0.669 (3)0.096 (3)0.098 (6)0.30
F1''0.102 (3)0.685 (4)0.094 (3)0.108 (10)0.20
F2''0.273 (6)0.776 (3)0.0344 (18)0.090 (6)0.20
F3''0.394 (5)0.524 (2)0.166 (2)0.104 (9)0.20
N10.2276 (2)0.40564 (18)0.09096 (15)0.0368 (4)
H10.23730.36380.00340.044*
O10.2404 (2)0.27853 (15)0.58734 (12)0.0395 (3)
O20.2518 (3)0.23117 (19)0.81527 (14)0.0599 (5)
O30.1836 (3)0.65505 (17)0.22024 (15)0.0554 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0547 (12)0.0453 (10)0.0236 (7)0.0192 (9)0.0200 (8)0.0085 (6)
C20.0605 (13)0.0417 (10)0.0304 (8)0.0229 (9)0.0231 (8)0.0157 (7)
C30.0504 (12)0.0351 (9)0.0319 (8)0.0214 (8)0.0184 (8)0.0117 (7)
C40.0946 (19)0.0414 (11)0.0499 (10)0.0384 (12)0.0391 (12)0.0206 (8)
C50.0453 (11)0.0336 (8)0.0280 (7)0.0194 (8)0.0179 (7)0.0090 (6)
C60.0415 (10)0.0343 (8)0.0222 (7)0.0165 (7)0.0162 (7)0.0043 (6)
C70.0512 (11)0.0293 (8)0.0292 (7)0.0202 (8)0.0200 (7)0.0070 (6)
C80.0444 (10)0.0330 (8)0.0267 (7)0.0192 (7)0.0188 (7)0.0096 (6)
C90.0690 (14)0.0402 (9)0.0301 (8)0.0298 (9)0.0302 (9)0.0096 (7)
C100.0655 (13)0.0327 (8)0.0356 (8)0.0264 (9)0.0278 (9)0.0088 (7)
C110.0477 (11)0.0370 (9)0.0359 (8)0.0234 (8)0.0227 (8)0.0146 (7)
C120.0608 (15)0.0455 (11)0.0448 (10)0.0288 (10)0.0262 (11)0.0207 (8)
F10.078 (5)0.055 (4)0.056 (3)0.038 (4)0.052 (3)0.037 (3)
F20.102 (8)0.032 (3)0.066 (3)0.026 (4)0.043 (5)0.028 (2)
F30.049 (3)0.093 (8)0.056 (4)0.035 (5)0.011 (3)0.032 (5)
F1'0.23 (2)0.080 (10)0.067 (9)0.075 (15)0.088 (15)0.039 (7)
F2'0.067 (7)0.073 (8)0.070 (6)0.007 (4)0.030 (4)0.040 (5)
F3'0.056 (7)0.112 (15)0.127 (15)0.047 (10)0.030 (9)0.076 (11)
F1''0.078 (10)0.14 (2)0.119 (15)0.043 (14)0.058 (10)0.089 (16)
F2''0.175 (18)0.073 (11)0.063 (7)0.083 (12)0.057 (12)0.038 (7)
F3''0.135 (16)0.072 (9)0.044 (5)0.035 (10)0.012 (7)0.007 (6)
N10.0603 (11)0.0358 (7)0.0268 (6)0.0268 (7)0.0245 (7)0.0120 (5)
O10.0628 (9)0.0376 (6)0.0253 (5)0.0235 (6)0.0240 (6)0.0071 (4)
O20.0991 (13)0.0576 (9)0.0330 (6)0.0343 (9)0.0380 (8)0.0094 (6)
O30.0959 (13)0.0392 (7)0.0502 (8)0.0366 (8)0.0420 (8)0.0136 (6)
Geometric parameters (Å, º) top
C1—O21.215 (2)C8—N11.417 (2)
C1—O11.367 (2)C9—C101.373 (2)
C1—C21.434 (3)C9—H90.9300
C2—C31.345 (2)C10—H100.9300
C2—H20.9300C11—O31.209 (2)
C3—C51.454 (2)C11—N11.337 (2)
C3—C41.499 (2)C11—C121.542 (2)
C4—H4A0.9600C12—F1''1.23 (2)
C4—H4B0.9600C12—F1'1.259 (19)
C4—H4C0.9600C12—F31.287 (8)
C5—C61.393 (2)C12—F21.297 (8)
C5—C101.403 (2)C12—F3'1.327 (15)
C6—O11.3835 (17)C12—F2''1.327 (14)
C6—C71.384 (2)C12—F11.343 (7)
C7—C81.388 (2)C12—F2'1.400 (18)
C7—H70.9300C12—F3''1.42 (2)
C8—C91.398 (2)N1—H10.8600
O2—C1—O1116.61 (16)F1'—C12—F3'111.2 (12)
O2—C1—C2125.67 (16)F3—C12—F3'30.8 (9)
O1—C1—C2117.72 (13)F2—C12—F3'84.4 (9)
C3—C2—C1123.21 (15)F1''—C12—F2''114.2 (12)
C3—C2—H2118.4F1'—C12—F2''134.9 (11)
C1—C2—H2118.4F3—C12—F2''72.7 (13)
C2—C3—C5118.12 (15)F2—C12—F2''42.9 (14)
C2—C3—C4121.53 (15)F3'—C12—F2''42.7 (10)
C5—C3—C4120.35 (14)F1''—C12—F127.2 (16)
C3—C4—H4A109.5F1'—C12—F122.9 (14)
C3—C4—H4B109.5F3—C12—F1105.9 (5)
H4A—C4—H4B109.5F2—C12—F1106.3 (5)
C3—C4—H4C109.5F3'—C12—F1129.8 (11)
H4A—C4—H4C109.5F2''—C12—F1135.9 (10)
H4B—C4—H4C109.5F1''—C12—F2'59.8 (14)
C6—C5—C10116.77 (14)F1'—C12—F2'105.0 (11)
C6—C5—C3118.39 (13)F3—C12—F2'123.9 (9)
C10—C5—C3124.81 (14)F2—C12—F2'20.2 (10)
O1—C6—C7115.01 (13)F3'—C12—F2'101.2 (11)
O1—C6—C5121.47 (13)F2''—C12—F2'62.0 (14)
C7—C6—C5123.52 (13)F1—C12—F2'87.0 (9)
C6—C7—C8117.96 (14)F1''—C12—F3''104.1 (14)
C6—C7—H7121.0F1'—C12—F3''59.8 (11)
C8—C7—H7121.0F3—C12—F3''28.5 (10)
C7—C8—C9120.26 (14)F2—C12—F3''135.5 (9)
C7—C8—N1122.56 (14)F3'—C12—F3''59.3 (10)
C9—C8—N1117.18 (12)F2''—C12—F3''100.8 (12)
C10—C9—C8120.32 (13)F1—C12—F3''82.7 (15)
C10—C9—H9119.8F2'—C12—F3''139.8 (12)
C8—C9—H9119.8F1''—C12—C11120.0 (10)
C9—C10—C5121.17 (14)F1'—C12—C11115.8 (9)
C9—C10—H10119.4F3—C12—C11111.5 (4)
C5—C10—H10119.4F2—C12—C11109.2 (4)
O3—C11—N1127.88 (15)F3'—C12—C11109.6 (8)
O3—C11—C12117.70 (15)F2''—C12—C11108.7 (5)
N1—C11—C12114.40 (14)F1—C12—C11112.2 (4)
F1''—C12—F1'47.4 (13)F2'—C12—C11113.0 (8)
F1''—C12—F3119.8 (13)F3''—C12—C11106.8 (10)
F1'—C12—F384.0 (13)C11—N1—C8126.56 (12)
F1''—C12—F279.3 (15)C11—N1—H1116.7
F1'—C12—F2122.1 (9)C8—N1—H1116.7
F3—C12—F2111.5 (6)C1—O1—C6121.07 (13)
F1''—C12—F3'130.4 (13)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.862.052.8960 (19)170
Symmetry code: (i) x, y, z1.

Experimental details

Crystal data
Chemical formulaC12H8F3NO3
Mr271.19
Crystal system, space groupTriclinic, P1
Temperature (K)293
a, b, c (Å)8.4897 (17), 8.5777 (17), 9.3677 (19)
α, β, γ (°)89.36 (3), 68.27 (3), 65.12 (3)
V3)566.3 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.15
Crystal size (mm)0.33 × 0.25 × 0.22
Data collection
DiffractometerRigaku R-AXIS RAPID
Absorption correctionMulti-scan
(ABSCOR; Higashi, 1995)
Tmin, Tmax0.954, 0.968
No. of measured, independent and
observed [I > 2σ(I)] reflections
5577, 2558, 1660
Rint0.025
(sin θ/λ)max1)0.649
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.046, 0.143, 1.01
No. of reflections2558
No. of parameters227
No. of restraints84
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.32, 0.29

Computer programs: RAPID-AUTO (Rigaku, 1998), CrystalStructure (Rigaku/MSC and Rigaku, 2002), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.862.052.8960 (19)170.0
Symmetry code: (i) x, y, z1.
 

Acknowledgements

The authors acknowledge financial support from the National Natural Science Foundation of China (grant No. 21062022) and the Open Project of the State Key Laboratory of Supra­molecular Structure and Materials, Jilin Universty.

References

First citationHigashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.  Google Scholar
First citationLi, H. Q., Cai, L. & Chen, Z. (2012). Advances in Chemical Sensors, Coumarin-Derived Flurescent Chemosensors, p. 121. Rijeka, Croatia: Intech.  Google Scholar
First citationLi, H. D., Li, B., Jin, L. Y., Kan, Y. H. & Yin, B. Z. (2011). Tetrahedron, 67, 7348–7353.  Web of Science CSD CrossRef CAS Google Scholar
First citationRigaku (1998). RAPID-AUTO. Rigaku Corporation, Tokyo, Japan.  Google Scholar
First citationRigaku/MSC & Rigaku (2002). CrystalStructure. Rigaku/MSC Inc., The Woodlands, Texas, USA.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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