(Z)-2-(4-tert-Butyl­phen­yl)-1-(4-chloro-1-ethyl-3-methyl-1H-pyrazol-5-yl)-2-cyano­vinyl pivalate

Bao Wang; Haibo Yu; Bin Li

doi:10.1107/S1600536811027255

. 2011 Jul 13;67(Pt 8):o2027. doi: 10.1107/S1600536811027255

(Z)-2-(4-tert-Butylphenyl)-1-(4-chloro-1-ethyl-3-methyl-1H-pyrazol-5-yl)-2-cyanovinyl pivalate

Bao Wang ^a, Haibo Yu ^b, Bin Li ^b,^*

PMCID: PMC3213477 PMID: 22091056

Abstract

In the title compound, C₂₄H₃₀ClN₃O₂, the dihedral angle between the benzene and pyrazole rings is 56.86 (7)°. The C=C bond is significantly twisted, as indicated by the dihedral angle of 12.26 (1)° between the two sets of three atoms linked by the double bond.

Related literature

The bioactivity of isomers of acrylonitrile compounds often differ, see: Kenzo et al. (2006 ▶); Yang et al. (2009 ▶).

Experimental

Crystal data

C₂₄H₃₀ClN₃O₂
M _r = 427.96
Monoclinic,
a = 10.1796 (7) Å
b = 10.5648 (7) Å
c = 12.3632 (8) Å
β = 110.613 (1)°
V = 1244.48 (14) Å³
Z = 2
Mo Kα radiation
μ = 0.18 mm⁻¹
T = 296 K
0.38 × 0.34 × 0.28 mm

Data collection

Bruker SMART CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2001 ▶) T _min = 0.757, T _max = 1.000
6437 measured reflections
4354 independent reflections
3756 reflections with I > 2σ(I)
R _int = 0.014

Refinement

R[F ² > 2σ(F ²)] = 0.039
wR(F ²) = 0.100
S = 1.03
4354 reflections
276 parameters
1 restraint
H-atom parameters constrained
Δρ_max = 0.14 e Å⁻³
Δρ_min = −0.17 e Å⁻³
Absolute structure: Flack (1983 ▶), 2014 Friedel pairs
Flack parameter: 0.06 (6)

Data collection: SMART (Bruker, 2001 ▶); cell refinement: SAINT (Bruker, 2001 ▶); 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 and PLATON (Spek, 2009 ▶).

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536811027255/hb5916sup1.cif

e-67-o2027-sup1.cif^{(22.6KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811027255/hb5916Isup2.hkl

e-67-o2027-Isup2.hkl^{(213.3KB, hkl)}

Supplementary material file. DOI: 10.1107/S1600536811027255/hb5916Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

Acrylonitrile compounds display a broad range of biological, medical and pharmacological properties. There is a double bond in the molecule of the acrylonitrile compounds, and both geometric isomers referred to as the E- and Z-isomer can be present. The bioactivities of them often differ from each other (Kenzo et al., 2006; Yang et al. 2009). In the process of preparation of the title compound, its geometric isomer product was also afforded, which showed obviously different acaricidal activity with the title compound. In order to confirm the geometry configuration, we report the crystal structure of the title compound (I) in this paper. The molecular structure of (I) is shown in Fig. 1. The the benzene and pyrazole rings in each of the ligands are not coplanar, the dihedral angle formed by the least-squares planes of the benzene and pyrazole rings being equal to 56.86 (7)°. The dihedral angle between C7/C6/O1 and C15/C13/C14 is 12.26 (1)°. The C(14)—C(13)—C(15)—C(20), O(1)—C(6)—C(13)—C(14), C(7)—C(6)—C(13)—C(14) and C(5)—O(1)—C(6)—C(7) torsion angles are -44.9 (3), -13.6 (3), 172.1 (2) and -69.5 (2)°, respectively. The crystal packing of (I) shows in Fig. 2. No significant interactions, such as hydrogen bonds or pi-pi stacking, are observed in (I). Examination of this structure with PLATON(Spek, 2009) reveals no solvent-accessible voids in the unit cell.

Experimental

The title compound was synthesized by 2-(4-(tert-butyl) phenyl)-3-(4-chloro-1-ethyl-3-methyl-1H-pyrazol-5-yl) -3-hydroxyacrylonitrile with pivaloyl chloride in THF. The crude products were purified by silica-gel column chromatography and then grown from heptane to afford colorless blocks of (I). To the mixture of 2-(4-(tert-butyl)phenyl)-3-(4-chloro- 1-ethyl-3-methyl-1H-pyrazol-5-yl)-3-hydroxyacrylonitrile (0.69 g, 2.0 mmol) and triethyl amine (0.24 g, 2.4 mmol) in THF (10 ml), pivaloyl chloride (0.29 g, 2.4 mmol) was added dropwise at roomtemperature and reacted for 1 h. After separation through silica gel column chromatography (fluent: ethyl acetate/petroleum ether=1/20), The title product compound was gained as a white solid (0.13 g, 15%).

Anal. Calcd for C₂₄H₃₀Cl₁N₃O₂: C, 67.35; H, 7.07; Cl, 8.28; N, 9.82; O, 7.48. Found: C, 67.33; H, 7.11; N, Cl, 8.32; N, 9.85; O, 7.52. ¹H NMR(DMSO): 0.98 (s, 9H, CO(CH₃)₃), 1.27 (s, 9H, Ph-(CH₃)₃), 1.36 (t, 3H, CH₃), 2.25 (s, 3H, CH₃), 3.60 (q, 2H, N—CH₂), 7.06 (d, 2H, Ph), 7.31 (d, 2H, Ph).