Crystal structure of 5-[4-(di­methyl­amino)­phen­yl]-3-(4-methyl­phen­yl)-4,5-di­hydro-1H-pyrazole-1-carbaldehyde

Farook Adam; Seranthimata Samshuddin; Nadiah Ameram; Subramaya; Laxminarayana Samartha

doi:10.1107/S2056989015023294

. 2015 Dec 9;71(Pt 12):o1031–o1032. doi: 10.1107/S2056989015023294

Crystal structure of 5-[4-(dimethylamino)phenyl]-3-(4-methylphenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde

Farook Adam ^a,^*, Seranthimata Samshuddin ^b, Nadiah Ameram ^a, Subramaya ^b, Laxminarayana Samartha ^b

PMCID: PMC4719963 PMID: 26870482

Abstract

The title compound, C₁₉H₂₁N₃O, comprises a central pyrazole ring which is N-connected to an aldehyde group and C-connected twice to substituted benzene rings. The pyrazole ring is twisted on the C—C single bond, and the least-squares plane through this ring forms dihedral angles of 82.44 (5) and 4.52 (5)° with the (dimethylamino)benzene and p-tolyl rings, respectively. In the crystal, weak C—H⋯O hydrogen bonds link molecules into supramolecular tubes along the b axis.

Keywords: crystal structure, substituted pyrazole, pyrazole derivatives, pharmacological properties

Related literature

For pharmacological properties of pyrazole derivatives, see: Sarojini et al. (2010 ▸); Samshuddin et al. (2012 ▸). For their industrial applications, see: Wiley et al. (1958 ▸); Lu et al. (1999 ▸). For related structures, see Fun et al. (2010 ▸); Baktır et al. (2011 ▸).

Experimental

Crystal data

C₁₉H₂₁N₃O
M _r = 307.39
Monoclinic,
a = 21.9524 (15) Å
b = 6.2511 (4) Å
c = 24.1521 (16) Å
β = 106.3069 (9)°
V = 3181.0 (4) Å³
Z = 8
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 100 K
0.45 × 0.26 × 0.15 mm

Data collection

Bruker APEX DUO CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Sheldrick, 1996 ▸) T _min = 0.921, T _max = 0.962
27492 measured reflections
4750 independent reflections
4090 reflections with I > 2σ(I)
R _int = 0.028

Refinement

R[F ² > 2σ(F ²)] = 0.043
wR(F ²) = 0.122
S = 1.04
4750 reflections
211 parameters
H-atom parameters constrained
Δρ_max = 0.37 e Å⁻³
Δρ_min = −0.22 e Å⁻³

Data collection: APEX2 (Bruker, 2014 ▸); cell refinement: SAINT (Bruker, 2014 ▸); data reduction: SAINT; program(s) used to solve structure: SHELXS2013 (Sheldrick, 2008 ▸); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015 ▸); molecular graphics: SHELXTL (Sheldrick, 2008 ▸); software used to prepare material for publication: PLATON (Spek, 2009 ▸).

Supplementary Material

Crystal structure: contains datablock(s) I, New_Global_Publ_Block. DOI: 10.1107/S2056989015023294/tk5413sup1.cif

e-71-o1031-sup1.cif^{(953.5KB, cif)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S2056989015023294/tk5413Isup2.hkl

e-71-o1031-Isup2.hkl^{(378.6KB, hkl)}

Click here for additional data file.^{(6.6KB, cml)}

Supporting information file. DOI: 10.1107/S2056989015023294/tk5413Isup3.cml

Click here for additional data file.^{(1.2MB, tif)}

. DOI: 10.1107/S2056989015023294/tk5413fig1.tif

The molecular structure of (I), showing the atom labels and 50% probability displacement ellipsoids.

Click here for additional data file.^{(3.6MB, tif)}

b . DOI: 10.1107/S2056989015023294/tk5413fig2.tif

The crystal packing of (I), viewed along the b axis.

CCDC reference: 1440601

Additional supporting information: crystallographic information; 3D view; checkCIF report

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

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C1—H1A⋯O1ⁱ	0.95	2.52	3.4175 (12)	158
C19—H19A⋯O1ⁱⁱ	0.98	2.45	3.3902 (15)	161

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

Acknowledgments

SS thanks Alva’s Education Foundation, Moodbidri, for providing research facilities. The authors would like to thank Universiti Malaysia Kelantan, SLAI, the Malaysian Ministry of Higher Education and the Universiti Sains Malaysia for RU research grants (Nos. PKIMIA/846017 and 1001/PKIMIA/811269), which partly supported this work.

supplementary crystallographic information

S1. Introduction

Pyrazolyl derivatives are well known for their versatile pharmacological activities (Sarojini et al., 2010; Samshuddin et al., 2012). In addition, many 1,3,5-triaryl-2-pyrazolyls have a variety of industrial applications such as functioning as scintillation solutes (Wiley et al., 1958) and fluorescent agents (Lu et al., 1999). The crystal structures of some pyrazolyls containing a N-alkyl chain viz., 3,5-bis(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde (Baktır et al., 2011) and 1-[3,5-bis(4-fluorophenyl)-4,5-dihydro-1H-pyrazol-1-yl]ethanone (Fun et al., 2010) have been reported. In view of the importance of pyrazolines, the title compound (I) was prepared and its crystal structure reported.

S2. Supramolecular features

The asymmetric unit of (I) consists of a single crystallographic independent molecule as shown in Fig. 1. The pyrazoline ring (N1/N2/C7/C8/C9) is twisted about the C8—C7 bond [Q2 = 0.0964 (10) Å and φ2 = 133.5 (6)°] with maximum deviations of 0.057 (1) and −0.053 (1) Å from its mean plane for atoms C7 and C8, respectively. The methyl-substituted phenyl ring (C10–C15) and dimethylamino-substituted phenyl ring (C1–C6) make dihedral angles of 4.52 (5) and 82.44 (5)°, respectively, with the pyrazoline ring. In crystal, molecules are connected by weak C—H···O hydrogen bonds into one-dimensional spiral-like chains (Fig. 2), propagating along the crystallographic b-axis.

S3. Synthesis and crystallization

A mixture of (2E)-3-[4-(dimethylamino)phenyl]-1-(4-methylphenyl)prop-2-en-1-one (2.65 g, 0.01 mol) and hydrazine hydrate (1 ml) in 30 ml formic acid was refluxed for 6 h. The reaction mixture was cooled and poured into 250 ml ice-cold water. The precipitate formed was collected by filtration and purified by recrystallization from ethanol. Single crystals were grown from ethyl acetate by slow evaporation (m.p 473–476 K; yield: 68%).

S4. Refinement

The carbon-bound H-atoms were placed in calculated positions (C—H = 0.95–1.00 Å) and were included in the refinement in the riding model approximation, with U_iso(H) set to 1.2–1.5U_equiv(C) A rotating group model was applied to methyl groups.