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ISSN: 2056-9890

2-tert-Butyl-4-chloro-5-[4-(2-fluoro­eth­­oxy)benz­yl­oxy]pyridazin-3(2H)-one

aKey Laboratory of Radiopharmaceuticals, Ministry of Education, College of Chemistry, Beijing Normal University, 19 Xinjiekou Outer St, Beijing 100875, People's Republic of China
*Correspondence e-mail: zhangxzh@gmail.com

(Received 5 January 2012; accepted 7 May 2012; online 12 May 2012)

In the title compound, C17H20ClFN2O3, the dihedral angle between the pyridazine and benzene rings is 41.37 (10)°. In the crystal, there are no significant intermolecular interactions present. The terminal –CH2F group is disordered over two sets of sites with an occupancy ratio of 0.737 (2):0.263 (2).

Related literature

For details of the synthesis, see: Mou et al. (2010[Mou, T. T., Jing, H. H., Yang, W. J., Fang, W., Peng, C., Guo, F., Zhang, X. Z., Pang, Y. & Ma, Y. C. (2010). Bioorg. Med. Chem. 18, 1312-1320.], 2012[Mou, T. T., Zhao, Z. Q., Fang, W., Peng, C., Guo, F., Liu, B. L., Ma, Y. C. & Zhang, X. Z. (2012). J. Nucl. Med. 53, 472-479.]). For possible applications of the title compound as a myocardial perfusion imaging agent for positron emission tomography (when labelled with 18F), see: Mou et al. (2011[Mou, T. T., Zhao, Z. Q., Fang, W., Peng, C., Zhang, X. Z. & Liu, B. L. (2011). J. Nucl. Med. 52(Suppl. 1), 77.]); Mou et al. (2012[Mou, T. T., Zhao, Z. Q., Fang, W., Peng, C., Guo, F., Liu, B. L., Ma, Y. C. & Zhang, X. Z. (2012). J. Nucl. Med. 53, 472-479.]).

[Scheme 1]

Experimental

Crystal data
  • C17H20ClFN2O3

  • Mr = 354.80

  • Triclinic, [P \overline 1]

  • a = 8.7170 (14) Å

  • b = 9.5850 (16) Å

  • c = 11.8524 (19) Å

  • α = 110.475 (2)°

  • β = 107.185 (2)°

  • γ = 96.424 (3)°

  • V = 860.3 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.25 mm−1

  • T = 150 K

  • 0.47 × 0.38 × 0.35 mm

Data collection
  • Bruker APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.892, Tmax = 0.918

  • 4337 measured reflections

  • 3090 independent reflections

  • 2788 reflections with I > 2σ(I)

  • Rint = 0.016

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.094

  • S = 1.05

  • 3090 reflections

  • 227 parameters

  • H-atom parameters constrained

  • Δρmax = 0.32 e Å−3

  • Δρmin = −0.28 e Å−3

Data collection: APEX2 (Bruker, 2009[Bruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2009[Bruker (2009). 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

Myocardial uptake of the pyridaben analogues, which is correlated with blood flow, makes them potential myocardial perfusion imaging (MPI) agents for the positron emission tomography (PET) when labeled with 18F (Mou et al., 2010; Mou et al., 2011; Mou et al., 2012). Thus, the development of pyridaben analogues may lead to discover new valuable PET MPI agents.

The molecular structure of the title compound (measured at 150 K) is shown in Fig. 1. The dihedral angle between the pyridazine ring and the benzene ring is 41.37 (10)°. The terminal CH2F group is disordered between two positions with occupancies 0.737 (2) for C1F1 and 0.263 (2) for C1AF1A.

Related literature top

For details of the synthesis, see: Mou et al. (2012); Mou et al. (2010). For possible applications of the title compound as a myocardial perfusion imaging agent for positron emission tomography (when labelled with 18F), see: Mou et al. (2011); Mou et al. (2012).

Experimental top

The synthesis route is shown in Fig. 2. The solution of tert-butylammonium fluoride (1 mmol in 1 ml tetrahydrofuran) was stirred in a stream of nitrogen at 110 °C to remove the solvent. Then 2-tert-butyl-4-chloro-5-(4-(2-tosylethoxy-ethoxy)-benzyloxy)-2H-pyridazin-3-one (compound I, 0.30 mmol in 3 ml anhydrous CH3CN) was added to the above evaporation residue, and refluxed for 40 min at 90 °C. After concentration under reduced pressure, the residue was chromatographed over a column of silica gel and eluted with the mixture of dichloromethane and methanol (100:1). The product was obtained as white solid. The product was then recrystallized from the mixture of hexane and methanol (2:1) yielding colorless crystals of the title compound suitable for the single-crystal X-ray diffraction.

Refinement top

The H atoms bound to C atoms were positioned geometrically and refined using a riding model, with C—H = 0.99 Å for CH2 groups, 0.95 Å for aryl and 0.98 Å for methyl H atoms, Uiso(H) =1.2Ueq(C) for CH2 groups and aryl, and Uiso(H) =1.5Ueq(C) for methyl H atoms.

Structure description top

Myocardial uptake of the pyridaben analogues, which is correlated with blood flow, makes them potential myocardial perfusion imaging (MPI) agents for the positron emission tomography (PET) when labeled with 18F (Mou et al., 2010; Mou et al., 2011; Mou et al., 2012). Thus, the development of pyridaben analogues may lead to discover new valuable PET MPI agents.

The molecular structure of the title compound (measured at 150 K) is shown in Fig. 1. The dihedral angle between the pyridazine ring and the benzene ring is 41.37 (10)°. The terminal CH2F group is disordered between two positions with occupancies 0.737 (2) for C1F1 and 0.263 (2) for C1AF1A.

For details of the synthesis, see: Mou et al. (2012); Mou et al. (2010). For possible applications of the title compound as a myocardial perfusion imaging agent for positron emission tomography (when labelled with 18F), see: Mou et al. (2011); Mou et al. (2012).

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT (Bruker, 2009); 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. Molecular structure of the title compound showing the atom labeling scheme and 30% probability displacement ellipsoids. H atoms are omitted for clarity.
[Figure 2] Fig. 2. The synthesis route of the title compound.
2-tert-Butyl-4-chloro-5-[4-(2-fluoroethoxy)benzyloxy]pyridazin- 3(2H)-one top
Crystal data top
C17H20ClFN2O3Z = 2
Mr = 354.80F(000) = 372
Triclinic, P1Dx = 1.370 Mg m3
Hall symbol: -P 1Melting point: 396 K
a = 8.7170 (14) ÅMo Kα radiation, λ = 0.71073 Å
b = 9.5850 (16) ÅCell parameters from 2518 reflections
c = 11.8524 (19) Åθ = 2.3–27.5°
α = 110.475 (2)°µ = 0.25 mm1
β = 107.185 (2)°T = 150 K
γ = 96.424 (3)°Column, colourless, colourless
V = 860.3 (2) Å30.47 × 0.38 × 0.35 mm
Data collection top
Bruker APEXII CCD area-detector
diffractometer
3090 independent reflections
Radiation source: fine-focus sealed tube2788 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.016
phi and ω scansθmax = 25.3°, θmin = 2.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
h = 610
Tmin = 0.892, Tmax = 0.918k = 1110
4337 measured reflectionsl = 1413
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)] = 0.036Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.094H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0431P)2 + 0.4066P]
where P = (Fo2 + 2Fc2)/3
3090 reflections(Δ/σ)max < 0.001
227 parametersΔρmax = 0.32 e Å3
0 restraintsΔρmin = 0.28 e Å3
Crystal data top
C17H20ClFN2O3γ = 96.424 (3)°
Mr = 354.80V = 860.3 (2) Å3
Triclinic, P1Z = 2
a = 8.7170 (14) ÅMo Kα radiation
b = 9.5850 (16) ŵ = 0.25 mm1
c = 11.8524 (19) ÅT = 150 K
α = 110.475 (2)°0.47 × 0.38 × 0.35 mm
β = 107.185 (2)°
Data collection top
Bruker APEXII CCD area-detector
diffractometer
3090 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2009)
2788 reflections with I > 2σ(I)
Tmin = 0.892, Tmax = 0.918Rint = 0.016
4337 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0360 restraints
wR(F2) = 0.094H-atom parameters constrained
S = 1.05Δρmax = 0.32 e Å3
3090 reflectionsΔρmin = 0.28 e Å3
227 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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)
C10.7610 (4)1.6895 (3)0.6672 (3)0.0356 (7)0.737 (2)
H1A0.74831.74630.75020.043*0.737 (2)
H1B0.87561.72790.67510.043*0.737 (2)
F10.6489 (2)1.71415 (19)0.56807 (19)0.0563 (5)0.737 (2)
C1A0.6652 (12)1.6621 (10)0.6292 (9)0.0356 (7)0.263 (2)
H1A10.59191.63890.54000.043*0.263 (2)
H1A20.60361.69570.68800.043*0.263 (2)
F1A0.8073 (7)1.7730 (6)0.6664 (5)0.0563 (5)0.263 (2)
C20.7295 (3)1.5215 (2)0.63796 (19)0.0357 (5)
H2A0.79271.50420.71420.043*
H2B0.61041.47800.61410.043*
C30.7804 (2)1.29834 (18)0.49589 (16)0.0253 (4)
C40.8406 (2)1.2381 (2)0.39752 (17)0.0301 (4)
H40.87871.30190.36070.036*
C50.8452 (2)1.08544 (19)0.35314 (16)0.0278 (4)
H50.88831.04560.28670.033*
C60.7879 (2)0.98912 (18)0.40407 (15)0.0224 (4)
C70.7268 (2)1.05060 (19)0.50116 (16)0.0267 (4)
H70.68610.98600.53630.032*
C80.7234 (2)1.2049 (2)0.54876 (17)0.0276 (4)
H80.68271.24540.61650.033*
C90.7940 (2)0.82347 (19)0.35594 (16)0.0271 (4)
H9A0.90740.81340.39440.032*
H9B0.71760.76430.37960.032*
C100.74817 (19)0.62230 (17)0.15061 (16)0.0205 (3)
C110.69499 (19)0.56701 (17)0.01958 (15)0.0196 (3)
C120.69623 (19)0.41371 (18)0.05951 (15)0.0205 (3)
C130.8067 (2)0.52043 (18)0.20730 (16)0.0244 (4)
H130.84500.55600.29860.029*
C140.7659 (2)0.16475 (18)0.05844 (16)0.0224 (4)
C150.8931 (2)0.1704 (2)0.12319 (19)0.0319 (4)
H15A0.86040.22090.18250.048*
H15B0.89840.06570.17140.048*
H15C1.00200.22810.05710.048*
C160.5943 (2)0.06939 (19)0.15633 (18)0.0324 (4)
H16A0.51410.07800.11270.049*
H16B0.59780.03830.19450.049*
H16C0.56120.10750.22440.049*
C170.8217 (2)0.09524 (19)0.03935 (18)0.0308 (4)
H17A0.93070.15640.10340.046*
H17B0.82860.01010.00490.046*
H17C0.74190.09460.08270.046*
Cl10.62207 (5)0.67867 (4)0.06075 (4)0.02475 (13)
N10.75585 (16)0.32789 (14)0.01074 (12)0.0199 (3)
N20.81035 (17)0.38114 (15)0.14042 (13)0.0241 (3)
O10.78194 (18)1.45135 (14)0.53292 (12)0.0356 (3)
O20.74477 (15)0.76678 (12)0.21681 (10)0.0246 (3)
O30.64984 (16)0.36158 (13)0.17774 (11)0.0292 (3)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0526 (19)0.0305 (15)0.0392 (17)0.0225 (17)0.0274 (16)0.0189 (13)
F10.0628 (11)0.0390 (9)0.0698 (12)0.0205 (8)0.0142 (9)0.0304 (9)
C1A0.0526 (19)0.0305 (15)0.0392 (17)0.0225 (17)0.0274 (16)0.0189 (13)
F1A0.0628 (11)0.0390 (9)0.0698 (12)0.0205 (8)0.0142 (9)0.0304 (9)
C20.0596 (13)0.0248 (9)0.0333 (10)0.0188 (9)0.0280 (10)0.0119 (8)
C30.0340 (10)0.0181 (8)0.0221 (8)0.0079 (7)0.0098 (7)0.0057 (7)
C40.0469 (11)0.0229 (9)0.0271 (9)0.0100 (8)0.0203 (8)0.0114 (7)
C50.0380 (10)0.0247 (9)0.0220 (9)0.0098 (7)0.0151 (8)0.0068 (7)
C60.0266 (9)0.0197 (8)0.0159 (8)0.0058 (7)0.0038 (7)0.0048 (6)
C70.0355 (10)0.0225 (8)0.0239 (9)0.0055 (7)0.0131 (7)0.0097 (7)
C80.0378 (10)0.0253 (9)0.0225 (9)0.0104 (7)0.0160 (8)0.0075 (7)
C90.0376 (10)0.0228 (9)0.0176 (8)0.0094 (7)0.0076 (7)0.0059 (7)
C100.0196 (8)0.0163 (7)0.0229 (8)0.0034 (6)0.0071 (7)0.0057 (7)
C110.0197 (8)0.0184 (8)0.0220 (8)0.0052 (6)0.0076 (6)0.0095 (7)
C120.0212 (8)0.0206 (8)0.0207 (8)0.0056 (6)0.0095 (7)0.0077 (7)
C130.0294 (9)0.0203 (8)0.0178 (8)0.0068 (7)0.0044 (7)0.0042 (7)
C140.0243 (8)0.0166 (8)0.0237 (9)0.0072 (6)0.0085 (7)0.0046 (7)
C150.0329 (10)0.0327 (10)0.0375 (10)0.0167 (8)0.0188 (8)0.0147 (8)
C160.0280 (10)0.0188 (8)0.0366 (10)0.0057 (7)0.0058 (8)0.0003 (8)
C170.0422 (11)0.0195 (8)0.0308 (10)0.0119 (8)0.0126 (8)0.0094 (7)
Cl10.0323 (2)0.0221 (2)0.0243 (2)0.01014 (16)0.01102 (17)0.01263 (17)
N10.0233 (7)0.0167 (7)0.0173 (7)0.0053 (5)0.0062 (6)0.0048 (5)
N20.0277 (8)0.0217 (7)0.0188 (7)0.0063 (6)0.0046 (6)0.0065 (6)
O10.0646 (9)0.0198 (6)0.0329 (7)0.0160 (6)0.0302 (7)0.0104 (5)
O20.0353 (7)0.0166 (6)0.0177 (6)0.0091 (5)0.0069 (5)0.0035 (5)
O30.0432 (7)0.0261 (6)0.0187 (6)0.0131 (5)0.0117 (5)0.0075 (5)
Geometric parameters (Å, º) top
C1—F11.400 (4)C9—H9B0.9900
C1—C21.497 (3)C10—O21.3405 (19)
C1—H1A0.9900C10—C111.361 (2)
C1—H1B0.9900C10—C131.426 (2)
C1A—F1A1.383 (11)C11—C121.444 (2)
C1A—C21.541 (9)C11—Cl11.7215 (16)
C1A—H1A10.9900C12—O31.2276 (19)
C1A—H1A20.9900C12—N11.400 (2)
C2—O11.425 (2)C13—N21.302 (2)
C2—H2A0.9900C13—H130.9500
C2—H2B0.9900C14—N11.5169 (19)
C3—O11.373 (2)C14—C171.518 (2)
C3—C81.385 (2)C14—C151.529 (2)
C3—C41.388 (2)C14—C161.531 (2)
C4—C51.381 (2)C15—H15A0.9800
C4—H40.9500C15—H15B0.9800
C5—C61.390 (2)C15—H15C0.9800
C5—H50.9500C16—H16A0.9800
C6—C71.383 (2)C16—H16B0.9800
C6—C91.501 (2)C16—H16C0.9800
C7—C81.393 (2)C17—H17A0.9800
C7—H70.9500C17—H17B0.9800
C8—H80.9500C17—H17C0.9800
C9—O21.450 (2)N1—N21.3469 (18)
C9—H9A0.9900
F1—C1—C2109.6 (2)H9A—C9—H9B108.6
F1—C1—H1A109.8O2—C10—C11118.74 (14)
C2—C1—H1A109.8O2—C10—C13124.85 (14)
F1—C1—H1B109.8C11—C10—C13116.40 (14)
C2—C1—H1B109.8C10—C11—C12122.61 (14)
H1A—C1—H1B108.2C10—C11—Cl1121.01 (12)
F1A—C1A—C2103.9 (6)C12—C11—Cl1116.38 (12)
F1A—C1A—H1A1111.0O3—C12—N1122.25 (14)
C2—C1A—H1A1111.0O3—C12—C11123.81 (15)
F1A—C1A—H1A2111.0N1—C12—C11113.94 (14)
C2—C1A—H1A2111.0N2—C13—C10123.44 (15)
H1A1—C1A—H1A2109.0N2—C13—H13118.3
O1—C2—C1106.72 (17)C10—C13—H13118.3
O1—C2—C1A110.7 (4)N1—C14—C17109.19 (13)
O1—C2—H2A110.4N1—C14—C15108.07 (13)
C1—C2—H2A110.4C17—C14—C15109.53 (14)
C1A—C2—H2A130.3N1—C14—C16109.30 (13)
O1—C2—H2B110.4C17—C14—C16108.73 (14)
C1—C2—H2B110.4C15—C14—C16111.99 (15)
C1A—C2—H2B81.7C14—C15—H15A109.5
H2A—C2—H2B108.6C14—C15—H15B109.5
O1—C3—C8124.76 (15)H15A—C15—H15B109.5
O1—C3—C4115.27 (15)C14—C15—H15C109.5
C8—C3—C4119.97 (15)H15A—C15—H15C109.5
C5—C4—C3120.07 (16)H15B—C15—H15C109.5
C5—C4—H4120.0C14—C16—H16A109.5
C3—C4—H4120.0C14—C16—H16B109.5
C4—C5—C6121.06 (16)H16A—C16—H16B109.5
C4—C5—H5119.5C14—C16—H16C109.5
C6—C5—H5119.5H16A—C16—H16C109.5
C7—C6—C5118.15 (15)H16B—C16—H16C109.5
C7—C6—C9121.02 (15)C14—C17—H17A109.5
C5—C6—C9120.83 (15)C14—C17—H17B109.5
C6—C7—C8121.73 (16)H17A—C17—H17B109.5
C6—C7—H7119.1C14—C17—H17C109.5
C8—C7—H7119.1H17A—C17—H17C109.5
C3—C8—C7119.02 (16)H17B—C17—H17C109.5
C3—C8—H8120.5N2—N1—C12124.27 (13)
C7—C8—H8120.5N2—N1—C14115.40 (12)
O2—C9—C6107.02 (13)C12—N1—C14120.33 (13)
O2—C9—H9A110.3C13—N2—N1119.34 (14)
C6—C9—H9A110.3C3—O1—C2117.83 (13)
O2—C9—H9B110.3C10—O2—C9118.79 (12)
C6—C9—H9B110.3

Experimental details

Crystal data
Chemical formulaC17H20ClFN2O3
Mr354.80
Crystal system, space groupTriclinic, P1
Temperature (K)150
a, b, c (Å)8.7170 (14), 9.5850 (16), 11.8524 (19)
α, β, γ (°)110.475 (2), 107.185 (2), 96.424 (3)
V3)860.3 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.25
Crystal size (mm)0.47 × 0.38 × 0.35
Data collection
DiffractometerBruker APEXII CCD area-detector
Absorption correctionMulti-scan
(SADABS; Bruker, 2009)
Tmin, Tmax0.892, 0.918
No. of measured, independent and
observed [I > 2σ(I)] reflections
4337, 3090, 2788
Rint0.016
(sin θ/λ)max1)0.600
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.036, 0.094, 1.05
No. of reflections3090
No. of parameters227
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.32, 0.28

Computer programs: APEX2 (Bruker, 2009), SAINT (Bruker, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), SHELXTL (Sheldrick, 2008).

 

Acknowledgements

We thank Dr Xuebin Deng, from the College of Chemistry, Beijing Normal University, for his kind help with the diffraction data collection. This work was supported by the National Natural Science Foundation of China (20871020), Beijing Natural Science Foundation (2092018) and the Fundamental Research Funds for the Central Universities.

References

First citationBruker (2009). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
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