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

Jing, H.; Mou, T.; Zhang, X.

doi:10.1107/S1600536812020491

organic compounds

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ISSN: 2056-9890

Volume 68| Part 6| June 2012| Page o1707

https://doi.org/10.1107/S1600536812020491

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

Huihui Jing,^a Tiantian Mou ^a and Xianzhong Zhang ^a ^*

^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 , 2012 ). 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

Crystal data

C₁₇H₂₀ClFN₂O₃
M_r = 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 ) T_min = 0.892, T_max = 0.918
4337 measured reflections
3090 independent reflections
2788 reflections with I > 2σ(I)
R_int = 0.016

Refinement

R[F² > 2σ(F²)] = 0.036
wR(F²) = 0.094
S = 1.05
3090 reflections
227 parameters
H-atom parameters constrained
Δρ_max = 0.32 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT (Bruker, 2009); data reduction: SAINT; 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.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536812020491/aa2046sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536812020491/aa2046Isup4.hkl

Supporting information file. DOI: https://doi.org/10.1107/S1600536812020491/aa2046Isup3.cml

checkCIF report

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.

Structure description top

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

	Fig. 1. Molecular structure of the title compound showing the atom labeling scheme and 30% probability displacement ellipsoids. H atoms are omitted for clarity.
	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

C₁₇H₂₀ClFN₂O₃	Z = 2
M_r = 354.80	F(000) = 372
Triclinic, P1	D_x = 1.370 Mg m⁻³
Hall symbol: -P 1	Melting point: 396 K
a = 8.7170 (14) Å	Mo Kα radiation, λ = 0.71073 Å
b = 9.5850 (16) Å	Cell parameters from 2518 reflections
c = 11.8524 (19) Å	θ = 2.3–27.5°
α = 110.475 (2)°	µ = 0.25 mm⁻¹
β = 107.185 (2)°	T = 150 K
γ = 96.424 (3)°	Column, colourless, colourless
V = 860.3 (2) Å³	0.47 × 0.38 × 0.35 mm

Data collection top

Bruker APEXII CCD area-detector diffractometer	3090 independent reflections
Radiation source: fine-focus sealed tube	2788 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.016
phi and ω scans	θ_max = 25.3°, θ_min = 2.3°
Absorption correction: multi-scan (SADABS; Bruker, 2009)	h = −6→10
T_min = 0.892, T_max = 0.918	k = −11→10
4337 measured reflections	l = −14→13

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)] = 0.036	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.094	H-atom parameters constrained
S = 1.05	w = 1/[σ²(F_o²) + (0.0431P)² + 0.4066P] where P = (F_o² + 2F_c²)/3
3090 reflections	(Δ/σ)_max < 0.001
227 parameters	Δρ_max = 0.32 e Å⁻³
0 restraints	Δρ_min = −0.28 e Å⁻³

Crystal data top

C₁₇H₂₀ClFN₂O₃	γ = 96.424 (3)°
M_r = 354.80	V = 860.3 (2) Å³
Triclinic, P1	Z = 2
a = 8.7170 (14) Å	Mo Kα radiation
b = 9.5850 (16) Å	µ = 0.25 mm⁻¹
c = 11.8524 (19) Å	T = 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)
T_min = 0.892, T_max = 0.918	R_int = 0.016
4337 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.036	0 restraints
wR(F²) = 0.094	H-atom parameters constrained
S = 1.05	Δρ_max = 0.32 e Å⁻³
3090 reflections	Δρ_min = −0.28 e Å⁻³
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

	x	y	z	U_iso*/U_eq	Occ. (<1)
C1	0.7610 (4)	1.6895 (3)	0.6672 (3)	0.0356 (7)	0.737 (2)
H1A	0.7483	1.7463	0.7502	0.043*	0.737 (2)
H1B	0.8756	1.7279	0.6751	0.043*	0.737 (2)
F1	0.6489 (2)	1.71415 (19)	0.56807 (19)	0.0563 (5)	0.737 (2)
C1A	0.6652 (12)	1.6621 (10)	0.6292 (9)	0.0356 (7)	0.263 (2)
H1A1	0.5919	1.6389	0.5400	0.043*	0.263 (2)
H1A2	0.6036	1.6957	0.6880	0.043*	0.263 (2)
F1A	0.8073 (7)	1.7730 (6)	0.6664 (5)	0.0563 (5)	0.263 (2)
C2	0.7295 (3)	1.5215 (2)	0.63796 (19)	0.0357 (5)
H2A	0.7927	1.5042	0.7142	0.043*
H2B	0.6104	1.4780	0.6141	0.043*
C3	0.7804 (2)	1.29834 (18)	0.49589 (16)	0.0253 (4)
C4	0.8406 (2)	1.2381 (2)	0.39752 (17)	0.0301 (4)
H4	0.8787	1.3019	0.3607	0.036*
C5	0.8452 (2)	1.08544 (19)	0.35314 (16)	0.0278 (4)
H5	0.8883	1.0456	0.2867	0.033*
C6	0.7879 (2)	0.98912 (18)	0.40407 (15)	0.0224 (4)
C7	0.7268 (2)	1.05060 (19)	0.50116 (16)	0.0267 (4)
H7	0.6861	0.9860	0.5363	0.032*
C8	0.7234 (2)	1.2049 (2)	0.54876 (17)	0.0276 (4)
H8	0.6827	1.2454	0.6165	0.033*
C9	0.7940 (2)	0.82347 (19)	0.35594 (16)	0.0271 (4)
H9A	0.9074	0.8134	0.3944	0.032*
H9B	0.7176	0.7643	0.3796	0.032*
C10	0.74817 (19)	0.62230 (17)	0.15061 (16)	0.0205 (3)
C11	0.69499 (19)	0.56701 (17)	0.01958 (15)	0.0196 (3)
C12	0.69623 (19)	0.41371 (18)	−0.05951 (15)	0.0205 (3)
C13	0.8067 (2)	0.52043 (18)	0.20730 (16)	0.0244 (4)
H13	0.8450	0.5560	0.2986	0.029*
C14	0.7659 (2)	0.16475 (18)	−0.05844 (16)	0.0224 (4)
C15	0.8931 (2)	0.1704 (2)	−0.12319 (19)	0.0319 (4)
H15A	0.8604	0.2209	−0.1825	0.048*
H15B	0.8984	0.0657	−0.1714	0.048*
H15C	1.0020	0.2281	−0.0571	0.048*
C16	0.5943 (2)	0.06939 (19)	−0.15633 (18)	0.0324 (4)
H16A	0.5141	0.0780	−0.1127	0.049*
H16B	0.5978	−0.0383	−0.1945	0.049*
H16C	0.5612	0.1075	−0.2244	0.049*
C17	0.8217 (2)	0.09524 (19)	0.03935 (18)	0.0308 (4)
H17A	0.9307	0.1564	0.1034	0.046*
H17B	0.8286	−0.0101	−0.0049	0.046*
H17C	0.7419	0.0946	0.0827	0.046*
Cl1	0.62207 (5)	0.67867 (4)	−0.06075 (4)	0.02475 (13)
N1	0.75585 (16)	0.32789 (14)	0.01074 (12)	0.0199 (3)
N2	0.81035 (17)	0.38114 (15)	0.14042 (13)	0.0241 (3)
O1	0.78194 (18)	1.45135 (14)	0.53292 (12)	0.0356 (3)
O2	0.74477 (15)	0.76678 (12)	0.21681 (10)	0.0246 (3)
O3	0.64984 (16)	0.36158 (13)	−0.17774 (11)	0.0292 (3)

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0526 (19)	0.0305 (15)	0.0392 (17)	0.0225 (17)	0.0274 (16)	0.0189 (13)
F1	0.0628 (11)	0.0390 (9)	0.0698 (12)	0.0205 (8)	0.0142 (9)	0.0304 (9)
C1A	0.0526 (19)	0.0305 (15)	0.0392 (17)	0.0225 (17)	0.0274 (16)	0.0189 (13)
F1A	0.0628 (11)	0.0390 (9)	0.0698 (12)	0.0205 (8)	0.0142 (9)	0.0304 (9)
C2	0.0596 (13)	0.0248 (9)	0.0333 (10)	0.0188 (9)	0.0280 (10)	0.0119 (8)
C3	0.0340 (10)	0.0181 (8)	0.0221 (8)	0.0079 (7)	0.0098 (7)	0.0057 (7)
C4	0.0469 (11)	0.0229 (9)	0.0271 (9)	0.0100 (8)	0.0203 (8)	0.0114 (7)
C5	0.0380 (10)	0.0247 (9)	0.0220 (9)	0.0098 (7)	0.0151 (8)	0.0068 (7)
C6	0.0266 (9)	0.0197 (8)	0.0159 (8)	0.0058 (7)	0.0038 (7)	0.0048 (6)
C7	0.0355 (10)	0.0225 (8)	0.0239 (9)	0.0055 (7)	0.0131 (7)	0.0097 (7)
C8	0.0378 (10)	0.0253 (9)	0.0225 (9)	0.0104 (7)	0.0160 (8)	0.0075 (7)
C9	0.0376 (10)	0.0228 (9)	0.0176 (8)	0.0094 (7)	0.0076 (7)	0.0059 (7)
C10	0.0196 (8)	0.0163 (7)	0.0229 (8)	0.0034 (6)	0.0071 (7)	0.0057 (7)
C11	0.0197 (8)	0.0184 (8)	0.0220 (8)	0.0052 (6)	0.0076 (6)	0.0095 (7)
C12	0.0212 (8)	0.0206 (8)	0.0207 (8)	0.0056 (6)	0.0095 (7)	0.0077 (7)
C13	0.0294 (9)	0.0203 (8)	0.0178 (8)	0.0068 (7)	0.0044 (7)	0.0042 (7)
C14	0.0243 (8)	0.0166 (8)	0.0237 (9)	0.0072 (6)	0.0085 (7)	0.0046 (7)
C15	0.0329 (10)	0.0327 (10)	0.0375 (10)	0.0167 (8)	0.0188 (8)	0.0147 (8)
C16	0.0280 (10)	0.0188 (8)	0.0366 (10)	0.0057 (7)	0.0058 (8)	0.0003 (8)
C17	0.0422 (11)	0.0195 (8)	0.0308 (10)	0.0119 (8)	0.0126 (8)	0.0094 (7)
Cl1	0.0323 (2)	0.0221 (2)	0.0243 (2)	0.01014 (16)	0.01102 (17)	0.01263 (17)
N1	0.0233 (7)	0.0167 (7)	0.0173 (7)	0.0053 (5)	0.0062 (6)	0.0048 (5)
N2	0.0277 (8)	0.0217 (7)	0.0188 (7)	0.0063 (6)	0.0046 (6)	0.0065 (6)
O1	0.0646 (9)	0.0198 (6)	0.0329 (7)	0.0160 (6)	0.0302 (7)	0.0104 (5)
O2	0.0353 (7)	0.0166 (6)	0.0177 (6)	0.0091 (5)	0.0069 (5)	0.0035 (5)
O3	0.0432 (7)	0.0261 (6)	0.0187 (6)	0.0131 (5)	0.0117 (5)	0.0075 (5)

Geometric parameters (Å, º) top

C1—F1	1.400 (4)	C9—H9B	0.9900
C1—C2	1.497 (3)	C10—O2	1.3405 (19)
C1—H1A	0.9900	C10—C11	1.361 (2)
C1—H1B	0.9900	C10—C13	1.426 (2)
C1A—F1A	1.383 (11)	C11—C12	1.444 (2)
C1A—C2	1.541 (9)	C11—Cl1	1.7215 (16)
C1A—H1A1	0.9900	C12—O3	1.2276 (19)
C1A—H1A2	0.9900	C12—N1	1.400 (2)
C2—O1	1.425 (2)	C13—N2	1.302 (2)
C2—H2A	0.9900	C13—H13	0.9500
C2—H2B	0.9900	C14—N1	1.5169 (19)
C3—O1	1.373 (2)	C14—C17	1.518 (2)
C3—C8	1.385 (2)	C14—C15	1.529 (2)
C3—C4	1.388 (2)	C14—C16	1.531 (2)
C4—C5	1.381 (2)	C15—H15A	0.9800
C4—H4	0.9500	C15—H15B	0.9800
C5—C6	1.390 (2)	C15—H15C	0.9800
C5—H5	0.9500	C16—H16A	0.9800
C6—C7	1.383 (2)	C16—H16B	0.9800
C6—C9	1.501 (2)	C16—H16C	0.9800
C7—C8	1.393 (2)	C17—H17A	0.9800
C7—H7	0.9500	C17—H17B	0.9800
C8—H8	0.9500	C17—H17C	0.9800
C9—O2	1.450 (2)	N1—N2	1.3469 (18)
C9—H9A	0.9900

F1—C1—C2	109.6 (2)	H9A—C9—H9B	108.6
F1—C1—H1A	109.8	O2—C10—C11	118.74 (14)
C2—C1—H1A	109.8	O2—C10—C13	124.85 (14)
F1—C1—H1B	109.8	C11—C10—C13	116.40 (14)
C2—C1—H1B	109.8	C10—C11—C12	122.61 (14)
H1A—C1—H1B	108.2	C10—C11—Cl1	121.01 (12)
F1A—C1A—C2	103.9 (6)	C12—C11—Cl1	116.38 (12)
F1A—C1A—H1A1	111.0	O3—C12—N1	122.25 (14)
C2—C1A—H1A1	111.0	O3—C12—C11	123.81 (15)
F1A—C1A—H1A2	111.0	N1—C12—C11	113.94 (14)
C2—C1A—H1A2	111.0	N2—C13—C10	123.44 (15)
H1A1—C1A—H1A2	109.0	N2—C13—H13	118.3
O1—C2—C1	106.72 (17)	C10—C13—H13	118.3
O1—C2—C1A	110.7 (4)	N1—C14—C17	109.19 (13)
O1—C2—H2A	110.4	N1—C14—C15	108.07 (13)
C1—C2—H2A	110.4	C17—C14—C15	109.53 (14)
C1A—C2—H2A	130.3	N1—C14—C16	109.30 (13)
O1—C2—H2B	110.4	C17—C14—C16	108.73 (14)
C1—C2—H2B	110.4	C15—C14—C16	111.99 (15)
C1A—C2—H2B	81.7	C14—C15—H15A	109.5
H2A—C2—H2B	108.6	C14—C15—H15B	109.5
O1—C3—C8	124.76 (15)	H15A—C15—H15B	109.5
O1—C3—C4	115.27 (15)	C14—C15—H15C	109.5
C8—C3—C4	119.97 (15)	H15A—C15—H15C	109.5
C5—C4—C3	120.07 (16)	H15B—C15—H15C	109.5
C5—C4—H4	120.0	C14—C16—H16A	109.5
C3—C4—H4	120.0	C14—C16—H16B	109.5
C4—C5—C6	121.06 (16)	H16A—C16—H16B	109.5
C4—C5—H5	119.5	C14—C16—H16C	109.5
C6—C5—H5	119.5	H16A—C16—H16C	109.5
C7—C6—C5	118.15 (15)	H16B—C16—H16C	109.5
C7—C6—C9	121.02 (15)	C14—C17—H17A	109.5
C5—C6—C9	120.83 (15)	C14—C17—H17B	109.5
C6—C7—C8	121.73 (16)	H17A—C17—H17B	109.5
C6—C7—H7	119.1	C14—C17—H17C	109.5
C8—C7—H7	119.1	H17A—C17—H17C	109.5
C3—C8—C7	119.02 (16)	H17B—C17—H17C	109.5
C3—C8—H8	120.5	N2—N1—C12	124.27 (13)
C7—C8—H8	120.5	N2—N1—C14	115.40 (12)
O2—C9—C6	107.02 (13)	C12—N1—C14	120.33 (13)
O2—C9—H9A	110.3	C13—N2—N1	119.34 (14)
C6—C9—H9A	110.3	C3—O1—C2	117.83 (13)
O2—C9—H9B	110.3	C10—O2—C9	118.79 (12)
C6—C9—H9B	110.3

Experimental details

Crystal data
Chemical formula	C₁₇H₂₀ClFN₂O₃
M_r	354.80
Crystal system, space group	Triclinic, 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)
V (Å³)	860.3 (2)
Z	2
Radiation type	Mo Kα
µ (mm⁻¹)	0.25
Crystal size (mm)	0.47 × 0.38 × 0.35

Data collection
Diffractometer	Bruker APEXII CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2009)
T_min, T_max	0.892, 0.918
No. of measured, independent and observed [I > 2σ(I)] reflections	4337, 3090, 2788
R_int	0.016
(sin θ/λ)_max (Å⁻¹)	0.600

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.036, 0.094, 1.05
No. of reflections	3090
No. of parameters	227
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	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

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