1-Allyl-4-(1,3-benzothia­zol-2-yl)-5-methyl-2-phenyl-1H-pyrazol-3(2H)-one

Imane Chakib; Abdelfettah Zerzouf; Hafid Zouihri; El Mokhtar Essassi; Seik Weng Ng

doi:10.1107/S1600536810040316

. 2010 Oct 20;66(Pt 11):o2842. doi: 10.1107/S1600536810040316

1-Allyl-4-(1,3-benzothiazol-2-yl)-5-methyl-2-phenyl-1H-pyrazol-3(2H)-one

Imane Chakib ^a, Abdelfettah Zerzouf ^a, Hafid Zouihri ^a, El Mokhtar Essassi ^a, Seik Weng Ng ^b,^*

PMCID: PMC3008974 PMID: 21589028

Abstract

The title compound, C₂₀H₁₇N₃OS, is a 1H-pyrazol-3(2H)-one having aromatic 4-(1,3-benzothiazol-2-yl)- and 2-phenyl substituents. The five-membered ring and fused ring system are planar, the r.m.s. deviations being 0.021 and 0.005 Å, respectively. The five-membered ring is aligned at 7.9 (2)° with respect to the fused-ring system. The allyl and phenyl parts of the molecule are both disordered over two positions in a 1:1 ratio. Weak intermolecular C—H⋯O hydrogen bonding is present in the crystal structure.

Related literature

For the structure of a related compound (E)-4-(2,3-dihydro-1,3-benzothiazol-2-ylidene)-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one, see: Chakibe et al. (2010 ▶).

Experimental

Crystal data

C₂₀H₁₇N₃OS
M _r = 347.43
Orthorhombic,
a = 17.8734 (5) Å
b = 10.4297 (2) Å
c = 18.9578 (4) Å
V = 3534.00 (14) Å³
Z = 8
Mo Kα radiation
μ = 0.20 mm⁻¹
T = 293 K
0.30 × 0.30 × 0.25 mm

Data collection

Bruker X8 APEXII diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▶) T _min = 0.944, T _max = 0.953
18349 measured reflections
3678 independent reflections
2341 reflections with I > 2σ(I)
R _int = 0.032

Refinement

R[F ² > 2σ(F ²)] = 0.050
wR(F ²) = 0.172
S = 1.00
3678 reflections
227 parameters
17 restraints
H-atom parameters constrained
Δρ_max = 0.32 e Å⁻³
Δρ_min = −0.25 e Å⁻³

Data collection: APEX2 (Bruker, 2008 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: X-SEED (Barbour, 2001 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810040316/xu5047sup1.cif

e-66-o2842-sup1.cif^{(23.6KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810040316/xu5047Isup2.hkl

e-66-o2842-Isup2.hkl^{(180.4KB, hkl)}

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

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯O1ⁱ	0.93	2.59	3.318 (3)	135
C12—H12A⋯O1ⁱⁱ	0.97	2.51	3.404 (4)	152
C12—H12C⋯O1ⁱⁱ	0.97	2.48	3.404 (4)	159

Open in a new tab

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

Acknowledgments

We thank Université Mohammed V-Agdal and the University of Malaya for supporting this study.

supplementary crystallographic information

Comment

(E)-4-(2,3-Dihydro-1,3-benzothiazol-2-ylidene)-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one is an amine that can under a nucleophilic substitution with organo bromides to form 2-substituted derivatives if tetra-n-butyl ammonium bromide is used as catalyst. In this study, the compound is reacted with allyl bromide to yield the title compound (Scheme I, Fig. 1).

Experimental

To a solution of (E)-4-(2,3-dihydro-1,3-benzothiazol-2-ylidene)-3-methyl-1-phenyl-1H-pyrazol-5(4H)-one (1 g, 3.25 mmol) in DMF (50 ml), was added sodium carbonate (2.5 g, 23 mmol), tetra-n-butyl ammonium bromide (0.15 g, 1 mmol) and allyl bromide (5.6 g, 46 mmol). The mixture was stirred for 24 h at room temperature. The solid material was removed by filtration and the solution was evaporated under reduced. The residue was washed with dichloromethane and hexane, and the recrystallized from ethanol to afford the title compound as colorless crystals.