organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 65| Part 5| May 2009| Page o1181

2-[3-Acetyl-5-(2-chloro-3-pyrid­yl)-2-methyl-2,3-di­hydro-1,3,4-oxa­diazol-2-yl]-4-fluoro­phenyl acetate

aThe State Key Laboratory Breeding Base of Green Chemistry–Synthesis Technology, College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310014, People's Republic of China
*Correspondence e-mail: qbsong@zjut.edu.cn

(Received 30 March 2009; accepted 24 April 2009; online 30 April 2009)

In the title compound, C18H15ClFN3O4, the dihedral angle between the substituted pyridine ring and the oxadiazo­line ring is 9.73 (19)° and the acyl group is coplanar with the oxadiazo­line ring [O—C—N—C torsion angle = −2.1 (3)°]. Furthermore, the substituted benzene ring is almost orthogonal with the oxadiazo­line ring, the dihedral angle between them being 87.56 (18)°.

Related literature

For background to 1,3,4-oxadiazo­line derivatives and related structures, see: Song et al. (2006a[Song, Q.-B., Zhang, J., Dong, Y. & Tiekink, E. R. T. (2006a). Acta Cryst. E62, o4388-o4390.],b[Song, Q.-B., Zhang, J. & Tiekink, E. R. T. (2006b). Acta Cryst. E62, o4115-o4117.]); Pan et al. (2007[Pan, L.-F., Lu, Y.-Q., Qin, Q., Qi, C.-Z. & Song, Q.-B. (2007). Acta Cryst. E63, o3988.]). For the pharmacological properties of 2,5-disubstituted 1,3,4-oxa­diazo­lines, see: Chimirri et al. (1994[Chimirri, A., Grasso, S., Monforte, A. M., Monforte, P., Zappala, M. & Carotti, A. (1994). Farmaco, 49, 509-511.], 1996[Chimirri, A., Grasso, S., Montforte, A. M., Rao, A. & Zappala, M. (1996). Farmaco, 51, 125-129.]); Dogan et al. (1998[Dogan, H. N., Duran, A., Rollas, S., Sener, G., Armutak, Y. & Keyer-Uysal, M. (1998). Med. Sci. Res., 26, 755-758.]).

[Scheme 1]

Experimental

Crystal data
  • C18H15ClFN3O4

  • Mr = 391.78

  • Monoclinic, P 21 /n

  • a = 10.120 (2) Å

  • b = 13.900 (3) Å

  • c = 13.320 (3) Å

  • β = 102.14 (3)°

  • V = 1831.8 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.25 mm−1

  • T = 293 K

  • 0.12 × 0.10 × 0.08 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2000[Bruker (2000). APEX2, SAINT and SADABS. Bruker AXS inc., Madison, Wisconsin, USA.]) Tmin = 0.971, Tmax = 0.981

  • 9882 measured reflections

  • 3403 independent reflections

  • 2394 reflections with I > 2σ(I)

  • Rint = 0.026

Refinement
  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.121

  • S = 1.00

  • 3403 reflections

  • 248 parameters

  • H-atom parameters not refined

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.22 e Å−3

Data collection: APEX2 (Bruker, 2000[Bruker (2000). APEX2, SAINT and SADABS. Bruker AXS inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2000[Bruker (2000). APEX2, SAINT and SADABS. Bruker AXS inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: SHELXTL.

Supporting information


Comment top

In continuation of our study of 1,3,4-oxadiazoline derivatives (Song et al., 2006a,b; Pan et al., 2007), which possess a wide range of pharmaceutical activities (Chimirri et al., 1994, 1996; Dogan et al., 1998), a series of new 1,3,4-oxadiazoline derivatives have been prepared. We present herein the crystal structure of the title compound, (I).

In (I), Fig. 1, the molecule is twisted about the C8—C9 bond. Within the five-membered oxadiazoline ring, there is a formal C13===N1 double bond (1.282 (3) Å). The bond distance of C13—O4 (1.360 (2) Å) is considerably shorter than the of C9—O4 bond (1.452 (2) Å), suggesting some delocalization of π-electron density over the O4—C13—N1 chromophore.

Related literature top

For background to 1,3,4-oxadiazoline derivatives and related structures, see: Song et al. (2006a,b); Pan et al. (2007). For some pharmacological properties of 2,5-disubstituted 1,3,4-oxadiazolines, see: Chimirri et al. (1994, 1996); Dogan et al. (1998).

Experimental top

A solution of 2-chloro-N'-(1-(5-fluoro-2-hydroxyphenyl)ethylidene) nicotinohydrazide (0.5 g, 1.62 mmol) in acetic anhydride (10 ml) was refluxed until the reaction was finished. The acetic anhydride was distilled under vacuum. The residue was recrystallized from ethanol (10 ml). Colorless crystals (0.46 g) were obtained by slow evaporation of an ethanol solution of (I) after 2 days at room temperature.

Refinement top

All H atoms were placed in calculated positions and allowed to ride on their parent atoms, with C—H = 0.93–0.96 Å and refined in the riding model approximation with Uiso(H) = 1.2—1.5Ueq(C).

Computing details top

Data collection: APEX2 (Bruker, 2000); cell refinement: SAINT (Bruker, 2000); data reduction: SAINT (Bruker, 2000); 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: SHELXTL (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. View of (I) showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 40% probability level. H atoms are represented by circles of arbitrary size.
2-[3-Acetyl-5-(2-chloro-3-pyridyl)-2-methyl-2,3-dihydro-1,3,4-oxadiazol- 2-yl]-4-fluorophenyl acetate top
Crystal data top
C18H15ClFN3O4F(000) = 808
Mr = 391.78Dx = 1.421 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3403 reflections
a = 10.120 (2) Åθ = 2.1–25.5°
b = 13.900 (3) ŵ = 0.25 mm1
c = 13.320 (3) ÅT = 293 K
β = 102.14 (3)°Block, colorless
V = 1831.8 (6) Å30.12 × 0.10 × 0.08 mm
Z = 4
Data collection top
Bruker APEXII CCD area-detector
diffractometer
3403 independent reflections
Radiation source: fine-focus sealed tube2394 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
ϕ and ω scansθmax = 25.5°, θmin = 2.1°
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
h = 127
Tmin = 0.971, Tmax = 0.981k = 1616
9882 measured reflectionsl = 1616
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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.121H-atom parameters not refined
S = 1.00 w = 1/[σ2(Fo2) + (0.06P)2 + 0.3383P]
where P = (Fo2 + 2Fc2)/3
3403 reflections(Δ/σ)max < 0.001
248 parametersΔρmax = 0.22 e Å3
0 restraintsΔρmin = 0.22 e Å3
Crystal data top
C18H15ClFN3O4V = 1831.8 (6) Å3
Mr = 391.78Z = 4
Monoclinic, P21/nMo Kα radiation
a = 10.120 (2) ŵ = 0.25 mm1
b = 13.900 (3) ÅT = 293 K
c = 13.320 (3) Å0.12 × 0.10 × 0.08 mm
β = 102.14 (3)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
3403 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2000)
2394 reflections with I > 2σ(I)
Tmin = 0.971, Tmax = 0.981Rint = 0.026
9882 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.121H-atom parameters not refined
S = 1.00Δρmax = 0.22 e Å3
3403 reflectionsΔρmin = 0.22 e Å3
248 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
xyzUiso*/Ueq
C10.0490 (3)0.1369 (2)0.5790 (2)0.0842 (8)
H1A0.00490.19430.56940.126*
H1B0.00100.08590.53830.126*
H1C0.13280.14850.55800.126*
C20.0772 (2)0.10902 (17)0.6890 (2)0.0686 (6)
C30.1358 (2)0.02657 (15)0.79837 (16)0.0566 (5)
C40.0293 (3)0.04387 (16)0.8454 (2)0.0702 (7)
H40.05760.02470.81400.084*
C50.0520 (3)0.08956 (18)0.9390 (2)0.0778 (7)
H50.01870.10210.97180.093*
C60.1815 (3)0.11600 (17)0.98264 (17)0.0729 (7)
C70.2892 (3)0.09887 (15)0.93740 (16)0.0627 (6)
H70.37580.11770.96990.075*
C80.2675 (2)0.05317 (14)0.84270 (15)0.0523 (5)
C90.3835 (2)0.03837 (14)0.78801 (14)0.0517 (5)
C100.5212 (2)0.07353 (16)0.84381 (18)0.0655 (6)
H10A0.51830.14190.85340.098*
H10B0.54540.04250.90950.098*
H10C0.58720.05850.80390.098*
C110.4183 (3)0.23549 (16)0.76258 (19)0.0731 (7)
H11A0.33030.26450.74780.110*
H11B0.44940.22680.69990.110*
H11C0.48010.27650.80800.110*
C120.4110 (2)0.14036 (15)0.81247 (16)0.0551 (5)
C130.35464 (19)0.02406 (16)0.61505 (14)0.0512 (5)
C140.3289 (2)0.06543 (17)0.51150 (15)0.0561 (5)
C150.3246 (2)0.16524 (19)0.50291 (18)0.0692 (6)
H150.34200.20320.56170.083*
C160.2944 (2)0.2080 (2)0.4075 (2)0.0806 (8)
H160.29130.27460.40090.097*
C170.2691 (3)0.1500 (3)0.3232 (2)0.0896 (9)
H170.24720.17910.25900.107*
C180.3038 (2)0.0137 (2)0.41987 (16)0.0655 (6)
Cl10.30866 (7)0.11042 (5)0.41760 (5)0.0845 (3)
F10.2064 (2)0.16130 (13)1.07494 (10)0.1092 (6)
N10.37927 (17)0.06330 (13)0.64394 (12)0.0543 (4)
N20.39054 (17)0.06139 (12)0.75037 (12)0.0525 (4)
N30.2739 (2)0.0537 (2)0.32705 (14)0.0793 (6)
O10.10784 (15)0.01308 (10)0.69914 (11)0.0612 (4)
O20.42063 (17)0.13026 (11)0.90474 (11)0.0697 (5)
O30.0761 (2)0.15939 (13)0.76138 (16)0.0960 (6)
O40.34983 (15)0.08897 (10)0.69061 (10)0.0569 (4)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0707 (17)0.0814 (18)0.097 (2)0.0185 (13)0.0106 (14)0.0250 (15)
C20.0516 (13)0.0587 (15)0.0921 (19)0.0046 (11)0.0072 (12)0.0006 (14)
C30.0683 (15)0.0453 (11)0.0562 (12)0.0010 (10)0.0132 (11)0.0100 (9)
C40.0750 (16)0.0595 (15)0.0802 (17)0.0053 (12)0.0258 (13)0.0181 (12)
C50.098 (2)0.0677 (16)0.0785 (18)0.0171 (15)0.0424 (16)0.0228 (14)
C60.116 (2)0.0610 (15)0.0452 (13)0.0158 (14)0.0260 (14)0.0094 (10)
C70.0875 (17)0.0523 (13)0.0470 (12)0.0097 (11)0.0112 (12)0.0046 (10)
C80.0686 (14)0.0409 (11)0.0462 (11)0.0038 (9)0.0097 (10)0.0070 (8)
C90.0636 (13)0.0448 (11)0.0434 (11)0.0005 (9)0.0036 (9)0.0021 (8)
C100.0662 (14)0.0631 (14)0.0630 (14)0.0084 (11)0.0038 (11)0.0152 (11)
C110.0900 (18)0.0493 (13)0.0749 (16)0.0044 (12)0.0058 (13)0.0103 (11)
C120.0573 (13)0.0493 (12)0.0531 (13)0.0000 (9)0.0012 (10)0.0032 (9)
C130.0449 (11)0.0609 (13)0.0457 (11)0.0075 (10)0.0048 (9)0.0037 (10)
C140.0425 (11)0.0771 (15)0.0474 (12)0.0085 (10)0.0065 (9)0.0007 (10)
C150.0611 (14)0.0862 (18)0.0574 (14)0.0141 (12)0.0058 (11)0.0118 (12)
C160.0746 (17)0.095 (2)0.0675 (17)0.0166 (14)0.0046 (13)0.0188 (14)
C170.0727 (18)0.132 (3)0.0597 (17)0.0181 (18)0.0046 (13)0.0288 (17)
C180.0463 (12)0.0983 (18)0.0509 (13)0.0108 (11)0.0077 (10)0.0046 (12)
Cl10.0910 (5)0.0999 (5)0.0607 (4)0.0095 (4)0.0117 (3)0.0222 (3)
F10.1671 (18)0.1102 (13)0.0567 (9)0.0254 (11)0.0381 (10)0.0077 (8)
N10.0541 (10)0.0628 (12)0.0431 (9)0.0031 (8)0.0033 (8)0.0088 (8)
N20.0628 (11)0.0474 (10)0.0429 (9)0.0000 (8)0.0011 (8)0.0065 (7)
N30.0658 (13)0.123 (2)0.0473 (12)0.0129 (13)0.0071 (9)0.0021 (11)
O10.0643 (9)0.0546 (9)0.0614 (9)0.0060 (7)0.0060 (7)0.0009 (7)
O20.0934 (12)0.0583 (9)0.0497 (9)0.0047 (8)0.0023 (8)0.0010 (7)
O30.1075 (15)0.0635 (11)0.1116 (16)0.0128 (10)0.0107 (12)0.0142 (11)
O40.0735 (10)0.0501 (8)0.0461 (8)0.0030 (7)0.0102 (7)0.0016 (6)
Geometric parameters (Å, º) top
C1—C21.484 (4)C10—H10B0.9600
C1—H1A0.9600C10—H10C0.9600
C1—H1B0.9600C11—C121.489 (3)
C1—H1C0.9600C11—H11A0.9600
C2—O31.194 (3)C11—H11B0.9600
C2—O11.369 (3)C11—H11C0.9600
C3—C41.377 (3)C12—O21.220 (2)
C3—C81.390 (3)C12—N21.364 (3)
C3—O11.405 (2)C13—N11.282 (3)
C4—C51.375 (3)C13—O41.360 (2)
C4—H40.9300C13—C141.466 (3)
C5—C61.367 (4)C14—C151.392 (3)
C5—H50.9300C14—C181.393 (3)
C6—F11.357 (3)C15—C161.377 (3)
C6—C71.373 (3)C15—H150.9300
C7—C81.388 (3)C16—C171.362 (4)
C7—H70.9300C16—H160.9300
C8—C91.520 (3)C17—N31.340 (4)
C9—O41.452 (2)C17—H170.9300
C9—N21.481 (2)C18—N31.331 (3)
C9—C101.516 (3)C18—Cl11.727 (3)
C10—H10A0.9600N1—N21.398 (2)
C2—C1—H1A109.5H10A—C10—H10C109.5
C2—C1—H1B109.5H10B—C10—H10C109.5
H1A—C1—H1B109.5C12—C11—H11A109.5
C2—C1—H1C109.5C12—C11—H11B109.5
H1A—C1—H1C109.5H11A—C11—H11B109.5
H1B—C1—H1C109.5C12—C11—H11C109.5
O3—C2—O1122.1 (2)H11A—C11—H11C109.5
O3—C2—C1127.7 (2)H11B—C11—H11C109.5
O1—C2—C1110.2 (2)O2—C12—N2119.22 (19)
C4—C3—C8122.2 (2)O2—C12—C11123.4 (2)
C4—C3—O1118.3 (2)N2—C12—C11117.36 (19)
C8—C3—O1119.31 (19)N1—C13—O4116.17 (17)
C5—C4—C3119.7 (3)N1—C13—C14129.68 (19)
C5—C4—H4120.1O4—C13—C14114.15 (18)
C3—C4—H4120.1C15—C14—C18116.4 (2)
C6—C5—C4118.2 (2)C15—C14—C13117.68 (19)
C6—C5—H5120.9C18—C14—C13125.8 (2)
C4—C5—H5120.9C16—C15—C14120.2 (2)
F1—C6—C5119.3 (3)C16—C15—H15119.9
F1—C6—C7117.7 (3)C14—C15—H15119.9
C5—C6—C7123.0 (2)C17—C16—C15118.2 (3)
C6—C7—C8119.4 (2)C17—C16—H16120.9
C6—C7—H7120.3C15—C16—H16120.9
C8—C7—H7120.3N3—C17—C16124.1 (2)
C7—C8—C3117.5 (2)N3—C17—H17118.0
C7—C8—C9120.5 (2)C16—C17—H17118.0
C3—C8—C9121.92 (18)N3—C18—C14124.3 (3)
O4—C9—N299.78 (14)N3—C18—Cl1113.72 (19)
O4—C9—C10107.50 (17)C14—C18—Cl1122.02 (18)
N2—C9—C10111.29 (17)C13—N1—N2104.80 (16)
O4—C9—C8107.64 (16)C12—N2—N1124.70 (17)
N2—C9—C8112.70 (16)C12—N2—C9124.06 (16)
C10—C9—C8116.38 (17)N1—N2—C9111.19 (15)
C9—C10—H10A109.5C18—N3—C17116.8 (2)
C9—C10—H10B109.5C2—O1—C3118.16 (18)
H10A—C10—H10B109.5C13—O4—C9107.56 (15)
C9—C10—H10C109.5
C8—C3—C4—C50.5 (3)C15—C14—C18—Cl1178.79 (16)
O1—C3—C4—C5174.88 (19)C13—C14—C18—Cl13.5 (3)
C3—C4—C5—C60.3 (3)O4—C13—N1—N21.3 (2)
C4—C5—C6—F1179.9 (2)C14—C13—N1—N2177.94 (19)
C4—C5—C6—C70.1 (4)O2—C12—N2—N1179.27 (18)
F1—C6—C7—C8179.65 (18)C11—C12—N2—N11.6 (3)
C5—C6—C7—C80.4 (3)O2—C12—N2—C92.1 (3)
C6—C7—C8—C30.2 (3)C11—C12—N2—C9178.74 (19)
C6—C7—C8—C9176.51 (19)C13—N1—N2—C12177.06 (19)
C4—C3—C8—C70.2 (3)C13—N1—N2—C95.5 (2)
O1—C3—C8—C7175.12 (17)O4—C9—N2—C12175.46 (18)
C4—C3—C8—C9176.90 (19)C10—C9—N2—C1271.3 (3)
O1—C3—C8—C91.5 (3)C8—C9—N2—C1261.5 (2)
C7—C8—C9—O4119.08 (18)O4—C9—N2—N17.0 (2)
C3—C8—C9—O457.5 (2)C10—C9—N2—N1106.21 (19)
C7—C8—C9—N2131.88 (18)C8—C9—N2—N1120.95 (17)
C3—C8—C9—N251.6 (2)C14—C18—N3—C170.5 (3)
C7—C8—C9—C101.6 (3)Cl1—C18—N3—C17179.67 (18)
C3—C8—C9—C10178.13 (18)C16—C17—N3—C180.8 (4)
N1—C13—C14—C15170.8 (2)O3—C2—O1—C31.4 (3)
O4—C13—C14—C1510.0 (3)C1—C2—O1—C3179.18 (19)
N1—C13—C14—C1811.5 (3)C4—C3—O1—C275.7 (2)
O4—C13—C14—C18167.70 (19)C8—C3—O1—C2108.7 (2)
C18—C14—C15—C161.0 (3)N1—C13—O4—C93.4 (2)
C13—C14—C15—C16176.9 (2)C14—C13—O4—C9177.29 (16)
C14—C15—C16—C170.1 (4)N2—C9—O4—C135.97 (19)
C15—C16—C17—N31.1 (4)C10—C9—O4—C13110.18 (18)
C15—C14—C18—N31.4 (3)C8—C9—O4—C13123.72 (16)
C13—C14—C18—N3176.3 (2)

Experimental details

Crystal data
Chemical formulaC18H15ClFN3O4
Mr391.78
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)10.120 (2), 13.900 (3), 13.320 (3)
β (°) 102.14 (3)
V3)1831.8 (6)
Z4
Radiation typeMo Kα
µ (mm1)0.25
Crystal size (mm)0.12 × 0.10 × 0.08
Data collection
DiffractometerBruker APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2000)
Tmin, Tmax0.971, 0.981
No. of measured, independent and
observed [I > 2σ(I)] reflections
9882, 3403, 2394
Rint0.026
(sin θ/λ)max1)0.606
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.121, 1.00
No. of reflections3403
No. of parameters248
H-atom treatmentH-atom parameters not refined
Δρmax, Δρmin (e Å3)0.22, 0.22

Computer programs: APEX2 (Bruker, 2000), SAINT (Bruker, 2000), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

This work was supported by the Key Discipline of Applied Chemistry, Zhejiang Province and the State Key Laboratory Breeding Base of Green Chemistry–Synthesis Technology, Zhejiang University of Technology (People's Republic of China).

References

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Volume 65| Part 5| May 2009| Page o1181
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