5-(4-Bromo­phen­yl)-3-(4-fluoro­phen­yl)-1-phenyl-4,5-dihydro-1H-pyrazole

Hoong-Kun Fun; Tze Shyang Chia; M Sapnakumari; B Narayana; B K Sarojini

doi:10.1107/S160053681203454X

. 2012 Aug 11;68(Pt 9):o2680. doi: 10.1107/S160053681203454X

5-(4-Bromophenyl)-3-(4-fluorophenyl)-1-phenyl-4,5-dihydro-1H-pyrazole

Hoong-Kun Fun ^a,^*,^‡, Tze Shyang Chia ^a, M Sapnakumari ^b, B Narayana ^b, B K Sarojini ^c

PMCID: PMC3435702 PMID: 22969573

Abstract

In the title compound, C₂₁H₁₆BrFN₂, the fluoro-substituted benzene ring is disordered over two orientations about the C—F bond and the C—C bond between the benzene and pyrazole groups with a site-occupancy ratio of 0.516 (8):0.484 (8). The central pyrazole ring [maximum deviation = 0.035 (3) Å] makes dihedral angles of 22.4 (2), 11.0 (2), 77.19 (16) and 7.44 (17)° with the two disorder components of the benzene ring, the bromo-substituted benzene ring and the phenyl ring, respectively. In the crystal, molecules are linked into a layer parallel to the bc plane through C—H⋯π interactions.

Related literature

For background to pyrazoline derivatives, see: Fun et al. (2010 ▶); Samshuddin et al. (2010 ▶, 2011 ▶). For a related structure, see: Samshuddin et al. (2010 ▶). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986 ▶).

Experimental

Crystal data

C₂₁H₁₆BrFN₂
M _r = 395.27
Monoclinic,
a = 20.5345 (5) Å
b = 5.2689 (1) Å
c = 16.1929 (5) Å
β = 104.443 (2)°
V = 1696.61 (7) Å³
Z = 4
Mo Kα radiation
μ = 2.44 mm⁻¹
T = 100 K
0.25 × 0.13 × 0.09 mm

Data collection

Bruker SMART APEXII CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2009 ▶) T _min = 0.583, T _max = 0.818
16716 measured reflections
4974 independent reflections
3761 reflections with I > 2σ(I)
R _int = 0.048

Refinement

R[F ² > 2σ(F ²)] = 0.051
wR(F ²) = 0.113
S = 1.01
4974 reflections
263 parameters
130 restraints
H-atom parameters constrained
Δρ_max = 1.26 e Å⁻³
Δρ_min = −0.99 e Å⁻³

Data collection: APEX2 (Bruker, 2009 ▶); cell refinement: SAINT (Bruker, 2009 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ▶).

Supplementary Material

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S160053681203454X/is5174sup1.cif

e-68-o2680-sup1.cif^{(30.5KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S160053681203454X/is5174Isup2.hkl

e-68-o2680-Isup2.hkl^{(243.6KB, hkl)}

Supplementary material file. DOI: 10.1107/S160053681203454X/is5174Isup3.cml

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

Table 1. Hydrogen-bond geometry (Å, °).

Cg1 is the centroid of the C10–C15 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C7—H7A⋯Cg1ⁱ	1.00	2.60	3.522 (3)	153
C17—H17A⋯Cg1ⁱⁱ	0.95	2.99	3.752 (6)	138

Open in a new tab

Symmetry codes: (i) Inline graphic ; (ii) .

Acknowledgments

HKF and TSC thank Universiti Sains Malaysia (USM) for the Research University Grant (1001/PFIZIK/811160). TSC also thanks the Malaysian Government and USM for the award of a research fellowship. BN thanks the UGC for financial assistance through the SAP and BSR one-time grant for the purchase of chemicals.

supplementary crystallographic information

Comment

In continuation of our work on synthesis of pyrazoline derivatives (Fun et al., 2010; Samshuddin et al., 2010, 2011), the title compound was prepared and its crystal structure is now reported.

The asymmetric unit of the title compound is shown in Fig. 1. The fluoro-substituted benzene ring is disordered over two positions (C16–C21 and C16/C17X/C18X/C19/C20X/C21X) rotated about the C9—C16···C19—F1 axis with a site-occupancy ratio of 0.516 (8):0.484 (8). The central pyrazole ring [N1/N2/C7–C9; maximum deviation = 0.035 (3) Å at atom C7] makes dihedral angles of 77.19 (16), 7.44 (17), 22.4 (2) and 11.0 (2)° with the C1–C6 (A), C10–C15 (B), C16–C21 (C) and C16/C17X/C18X/C19/C20X/C21X (D) benzene rings, respectively. The dihedral angles between the benzene rings are A/B = 83.25 (15)°, A/C = 87.1 (2)°, A/D = 67.2 (2)°, B/C = 22.6 (2)° and B/D = 16.1 (2)°. The bond lengths and angles are comparable to those found in a related structure (Samshuddin et al., 2010). In the crystal, molecules are linked into a layer parallel to (100) through intermolecular C—H···π interactions (Table 1), involving Cg1 which is the centroid of the C10–C15 ring.

Experimental

A mixture of (2E)-3-(4-bromophenyl)-1-(4-fluorophenyl)prop-2-en-1-one (3.05 g, 0.01 mol) and phenyl hydrazine (0.98 ml, 0.01 mol) in 50 ml of glacial acetic acid was refluxed for 6 h. The reaction mixture was cooled and poured into 50 ml ice-cold water. The precipitate was collected by filtration and purified by recrystallization from toluene. Orange blocks were grown from ethanol by slow evaporation method (m.p. 397–399 K).