4-[(4-Benzyl­oxybenzyl­idene)amino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one

Grzegorz Dutkiewicz; Divya N Shetty; B Narayana; H S Yathirajan; Maciej Kubicki

doi:10.1107/S1600536812014262

. 2012 Apr 6;68(Pt 5):o1324. doi: 10.1107/S1600536812014262

4-[(4-Benzyloxybenzylidene)amino]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one

Grzegorz Dutkiewicz ^a, Divya N Shetty ^b, B Narayana ^b, H S Yathirajan ^c, Maciej Kubicki ^a,^*

PMCID: PMC3344463 PMID: 22590225

Abstract

In the title molecule, C₂₅H₂₃N₃O₂, two terminal phenyl rings are twisted by 50.20 (6) and 71.26 (5)° from the mean plane (r.m.s. deviation = 0.032 Å) of the central benzylidene–amino–pyrazolone fragment. The N atoms of the pyrazole ring have a pyramidal environment, the sums of the valence angles around them being 353.5 (2) and 347.3 (2)°. The crystal structure is stabilized by C—H⋯O interactions.

Related literature

Related crystal structures have been described by Shi (2005 ▶), Jun (2005 ▶), Zhen et al. (2006 ▶), Liu et al. (2006 ▶), Diao & Chen (2006 ▶), Duan et al. (2006 ▶), Hu (2006 ▶) and Zhang et al. (2006 ▶).

Experimental

Crystal data

C₂₅H₂₃N₃O₂
M _r = 397.46
Monoclinic,
a = 19.8137 (19) Å
b = 6.1588 (4) Å
c = 18.0784 (14) Å
β = 108.881 (9)°
V = 2087.4 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 295 K
0.5 × 0.4 × 0.2 mm

Data collection

Agilent Xcalibur Eos diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011 ▶) T _min = 0.890, T _max = 1.000
8408 measured reflections
4352 independent reflections
3298 reflections with I > 2σ(I)
R _int = 0.018

Refinement

R[F ² > 2σ(F ²)] = 0.052
wR(F ²) = 0.119
S = 1.04
4352 reflections
363 parameters
All H-atom parameters refined
Δρ_max = 0.68 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Data collection: CrysAlis PRO (Agilent, 2011 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR92 (Altomare et al., 1993 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: XP in SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Crystal structure: contains datablock(s) I, global. DOI: 10.1107/S1600536812014262/cv5278sup1.cif

e-68-o1324-sup1.cif^{(29KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536812014262/cv5278Isup2.hkl

e-68-o1324-Isup2.hkl^{(208.9KB, hkl)}

Supplementary material file. DOI: 10.1107/S1600536812014262/cv5278Isup3.cml

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
C16—H16⋯O49ⁱ	0.990 (18)	2.486 (18)	3.470 (2)	172.6 (15)
C21—H21C⋯O5ⁱⁱ	0.97 (3)	2.58 (3)	3.352 (3)	137.3 (19)
C31—H31A⋯O5ⁱⁱ	0.97 (2)	2.65 (2)	3.517 (3)	149.1 (17)
C52—H52⋯O5ⁱⁱⁱ	0.96 (3)	2.51 (3)	3.411 (3)	156 (2)

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

Acknowledgments

BN thanks the UGC SAP for financial assistance for the purchase of chemicals. DNS thanks Mangalore University for research facilities.

supplementary crystallographic information

Comment

Pyrazolone, as a prominent structural motif, is found in numerous pharmaceutically active compounds. Due to the easy preparation and rich biological activity, pyrazolone framework plays an essential role and represents an interesting template for combinatorial and medicinal chemistry. Indeed, pyrazolone based derivatives have shown several biological activities such as analgesic, anti-inflammatory, antipyretic, antiarrhythmic, antifungal, muscle relaxing, psychoanaleptic, anticonvulsant, enzyme inhibiting, antidiabetic and antibacterial activities. So, the chemistry of pyrazolone and its derivatives is particularly interesting because of their potential application in medicinal chemistry. Here we present the results of the X-ray structure determination of the title compound, 1.

Quite recently, the crystal structures of a series of similar compounds, with substituted rings C and D (cf. Fig. 1) have been reported, namely, 3-methoxy (C),2,4-dichloro (D) (Zhen et al., 2006); 2,4-dichloro (D) (Liu et al., 2006); 3-methoxy (C), 4-nitro (D) (Diao & Chen, 2006); 3-methoxy (C), 4-chloro (D) (Duan et al., 2006); 4-chloro (D) (Hu, 2006); 3-ethoxy (C),4-chloro (D) (Zhang et al., 2006); 3-methoxy (C) (Shi, 2005), and 3-ethoxy (C) (Jun, 2005).

Compound 1, without additional substituents on the phenyl rings, might be regarded as the reference molecule. It has almost perfectly coplanar central part, consisting of two rings B and C (pyrazolone and phenyl) and the linking C—N=C—C chain (maximum deviation from the least-squares plane is 0.070 (1) Å). The dihedral angle between the planes of the two rings B and C is only 1.42 (13)°, and is significantly smaller than in the other similar molecules (6.21 (10)° - 39.24 (5)°). The overall conformation of the molecule might be described either by the dihedral angle between the planes of terminal phenyl rings (62.71 (6)°) or by the dihedral angles between the central plane and terminal ring planes (50.20 (6)° with ring A, 71.26 (5)° with ring D). These last values are generally consistent with those referred for similar compounds (48.05 (6)° - 72.97 (8)° for A, 39.49 (14)° - 86.16 (7)° for D).

In the pyrazolone ring, the N atoms of the pyrazole ring have pyramidal environment, sums of the valence angles around them are 353.5° for N1 and 347.3° for N2. The bond lengths pattern within this ring suggests significant delocalization and is also typical for these compounds, in contrast, the bond N41—C42 (1.276 (2) Å) has an obvious double-bond character.

In the crystal structure relatively short and linear C16—H16···O49ⁱ hydrogen bonds join molecules into centrosymmetric dimers; these dimers, in turn, by means of other, still weaker C—H···O contacts expand in two dimensions (Table 1, Fig. 2).

Experimental

The mixture of 4-amino-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (2.03 g, 0.01 mol) and 4-benzyloxybenzaldehyde (2.12 g, 0.01 mol) was refluxed in 30 ml e thanol with two drops of sulfuric acid for 3 h. The crude product obtained was filtered and recrystallized from ethanol. Good quality crystals were obtained by the evaporation of the solution in DMF (m.p: 438 K).