(4S,5R)-3-(4-Chloro­phen­yl)-5-(4-meth­oxy­phen­yl)-4-methyl-1-phenyl-4,5-di­hydro-1H-pyrazole

Ben Soumane, Y.; Baouid, A.; El Hadrami, E.M.; El Ammari, L.; Saadi, M.; Berraho, M.

doi:10.1107/S2414314616010221

organic compounds

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ISSN: 2414-3146

Volume 1| Part 6| June 2016| x161022

doi:10.1107/S2414314616010221

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(4S,5R)-3-(4-Chlorophenyl)-5-(4-methoxyphenyl)-4-methyl-1-phenyl-4,5-dihydro-1H-pyrazole

Yahya Ben Soumane,^a Abdesselam Baouid,^a El Mestafa El Hadrami,^a Lahcen El Ammari,^b Mohamed Saadi ^b and Moha Berraho ^c ^*

^aLaboratoire de Chimie Moléculaire, Faculté des Sciences Semlalia, BP 2390, Université Cadi Ayyad, 40001, Marrakech, Morocco, ^bLaboratoire de Chimie du Solide Appliquée, Faculty of Sciences, Mohammed V University in Rabat, Avenue Ibn Battouta, BP 1014, Rabat, Morocco, and ^cLaboratoire de Chimie des Substances Naturelles, URAC16, Faculté des Sciences Semlalia, BP 2390 Bd My Abdellah, 40000 Marrakech, Morocco
^*Correspondence e-mail: berraho@uca.ma

Edited by M. Bolte, Goethe-Universität Frankfurt Germany (Received 9 June 2016; accepted 22 June 2016; online 24 June 2016)

The title compound, C₂₃H₂₁ClN₂O, was obtained via the condensation of trans anethole [systematic name: (E)-1-Methoxy-4-(1-propenyl)benzene] with diarylnitrilimine. In the molecule, the pyrazole ring adopts a twisted conformation. Dihedral angles between the pyrazole group and the three aromatic subunits (chlorophenyl, methoxyphenyl and phenyl) are 9.44 (14), 83.14 (1) and 20.86 (15)°, respectively. In the crystal, no classic hydrogen bonds are found; however C—H⋯π interactions link the molecules into chains parallel to the c axis.

Keywords: crystal structure; pyrazole; C—H⋯π interactions.

CCDC reference: 1487208

Structure description

Trans-anethole is the active ingredient of the anise essential oil and the source of the anise scent. It has anticarcinogenic (Chainy et al., 2000 ), antigenotoxic (Abraham et al., 2001 ), gastroprotective and anti-oxidative (Freire et al., 2005 ), antithrombotic (Tognolini et al., 2007 ), antimicrobial and antiviral (Astani et al., 2011 ) properties. The double bond in the aromatic α position confers some reactivity. In this work, we focused our efforts on the preparation of new heterocyclic systems by the 1,3-dipolar cycloaddition reaction from trans-anethole and diarylnitrilimine. The condensation of trans-anethole with diarylnitrilimine generated in situ by the action of triethylamine on N-phenylarylohydrazonoyl chloride (Huisgen et al., 1962 ) is carried out in dichloromethane at room temperature. The obtained residue was purified by column chromatography on silica gel and the adduct was isolated in a satisfactory yield.

The structure of this new product (Fig. 1) was determined using its single-crystal X-ray diffraction data. The pyrazole ring has a twist conformation as indicated by the total puckering amplitude Q_T =0.158 (2) Å and φ =86.1 (8)°. The dihedral angles between the five-membered ring and the chlorophenyl, methoxyphenyl and phenyl rings are 9.44 (14), 83.14 (1) and 20.86 (15)°, respectively. The crystal structure features C—H⋯π interactions (Table 1), which link the molecules into chains parallel to the c axis as shown in Fig. 2.

Table 1
Hydrogen-bond geometry (Å, °)

Cg3 and Cg4 are the centroids of the C10–C15 and C16–C21 rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C2—H2⋯Cg3ⁱ	0.98	2.98	3.847 (3)	148
C23—H23C⋯Cg4ⁱⁱ	0.96	2.80	3.679 (3)	153
Symmetry codes: (i) $[x, -y-{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (ii) $[x, -y-{\script{1\over 2}}, z-{\script{3\over 2}}]$ .

Figure 1
The molecular structure of the title compound, showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level. H atoms are represented as small spheres of arbitrary radii.

Figure 2
Packing of the title compound showing molecules interconnected by C—H⋯π interactions and forming types parallel to the c-axis direction.

Synthesis and crystallization

Triethylamine (9 mmol) dissolved in dichloromethane (5 mL) was added dropwise to a solution of trans-anethole (6.74 mmol) and the precursor diarylnitrilimine (6.74 mmol) contained in a three-necked flask in dichloromethane (15 mL). After stirring for one day at room temperature, the mixture was washed several times with water (20 mL). The organic layers were separated, dried by anhydrous sodium sulfate, filtered and evaporated. The residue was purified in a silica-gel column (eluent: hexane/ethyl acetate 2/98), giving the title compound in 54% yield.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2.

Table 2
Experimental details

Crystal data
Chemical formula	C₂₃H₂₁ClN₂O
M_r	376.87
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	298
a, b, c (Å)	19.564 (16), 9.127 (8), 11.001 (10)
β (°)	94.88 (4)
V (Å³)	1957 (3)
Z	4
Radiation type	Mo Kα
μ (mm⁻¹)	0.21
Crystal size (mm)	0.30 × 0.26 × 0.17

Data collection
Diffractometer	Bruker X8 APEX
Absorption correction	Multi-scan (SADABS; Sheldrick, 2003 )
T_min, T_max	0.658, 0.747
No. of measured, independent and observed [I > 2σ(I)] reflections	16805, 3988, 1917
R_int	0.065
(sin θ/λ)_max (Å⁻¹)	0.625

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.049, 0.123, 0.97
No. of reflections	3988
No. of parameters	246
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.15, −0.22
Computer programs: APEX2 and SAINT-Plus (Bruker, 2009 ), SHELXS2014 (Sheldrick, 2008 ), SHELXL2014 (Sheldrick, 2015 ), ORTEP-3 for Windows (Farrugia, 2012 ) and publCIF (Westrip, 2010 ).

Structural data

CCDC reference: 1487208

Crystal structure: contains datablocks I, global. DOI: 10.1107/S2414314616010221/bt4016sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S2414314616010221/bt4016Isup2.hkl

Supporting information file. DOI: 10.1107/S2414314616010221/bt4016Isup3.cml

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2009); cell refinement: SAINT-Plus (Bruker, 2009); data reduction: SAINT-Plus (Bruker, 2009); program(s) used to solve structure: SHELXS2014 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012); software used to prepare material for publication: publCIF (Westrip, 2010).

(4S,5R)-3-(4-Chlorophenyl)-5-(4-methoxyphenyl)-4-methyl-1-phenyl-4,5-dihydro-1H-pyrazole top

Crystal data top

C₂₃H₂₁ClN₂O	F(000) = 792
M_r = 376.87	D_x = 1.279 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 19.564 (16) Å	Cell parameters from 3988 reflections
b = 9.127 (8) Å	θ = 2.5–26.4°
c = 11.001 (10) Å	µ = 0.21 mm⁻¹
β = 94.88 (4)°	T = 298 K
V = 1957 (3) Å³	Prism, colourless
Z = 4	0.30 × 0.26 × 0.17 mm

Data collection top

Bruker X8 APEX diffractometer	3988 independent reflections
Radiation source: fine-focus sealed tube	1917 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.065
φ and ω scans	θ_max = 26.4°, θ_min = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 2003)	h = −24→24
T_min = 0.658, T_max = 0.747	k = −11→11
16805 measured reflections	l = −7→13

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.123	H-atom parameters constrained
S = 0.97	w = 1/[σ²(F_o²) + (0.0513P)²] where P = (F_o² + 2F_c²)/3
3988 reflections	(Δ/σ)_max < 0.001
246 parameters	Δρ_max = 0.15 e Å⁻³
0 restraints	Δρ_min = −0.22 e Å⁻³

Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'s involving l.s. planes.

Refinement. Refinement of F² against all reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > 2σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on all data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	−0.04749 (4)	0.25816 (8)	0.48890 (8)	0.0981 (3)
O1	0.51903 (9)	0.34290 (18)	0.41122 (18)	0.0765 (5)
N2	0.25023 (10)	0.4231 (2)	0.05057 (19)	0.0617 (6)
N1	0.19177 (9)	0.43689 (19)	0.10970 (18)	0.0553 (5)
C4	0.35035 (11)	0.3054 (2)	0.1608 (2)	0.0485 (6)
C1	0.18069 (12)	0.3154 (2)	0.1641 (2)	0.0522 (6)
C10	0.26488 (12)	0.5215 (2)	−0.0399 (2)	0.0521 (6)
C3	0.28620 (12)	0.2843 (2)	0.0788 (2)	0.0554 (6)
H3	0.2971	0.2364	0.0030	0.066*
C8	0.41134 (12)	0.4210 (2)	0.3330 (2)	0.0553 (6)
H8	0.4138	0.4934	0.3927	0.066*
C9	0.35455 (12)	0.4104 (2)	0.2521 (2)	0.0539 (6)
H9	0.3181	0.4747	0.2584	0.065*
C2	0.23065 (11)	0.1962 (2)	0.1382 (2)	0.0551 (6)
H2	0.2502	0.1530	0.2150	0.066*
C7	0.46469 (12)	0.3248 (2)	0.3262 (2)	0.0537 (6)
C18	0.06354 (13)	0.1616 (3)	0.3852 (3)	0.0634 (7)
H18	0.0594	0.0769	0.4310	0.076*
C5	0.40490 (13)	0.2124 (2)	0.1551 (2)	0.0607 (7)
H5	0.4035	0.1421	0.0937	0.073*
C19	0.01805 (13)	0.2738 (3)	0.3930 (3)	0.0648 (7)
C16	0.12361 (12)	0.3001 (2)	0.2407 (2)	0.0523 (6)
C17	0.11574 (12)	0.1745 (2)	0.3091 (2)	0.0590 (7)
H17	0.1463	0.0973	0.3036	0.071*
C11	0.32179 (13)	0.5030 (3)	−0.1049 (2)	0.0584 (6)
H11	0.3523	0.4269	−0.0847	0.070*
C15	0.22128 (13)	0.6379 (2)	−0.0700 (2)	0.0657 (7)
H15	0.1835	0.6542	−0.0259	0.079*
C21	0.07674 (13)	0.4117 (3)	0.2509 (2)	0.0646 (7)
H21	0.0806	0.4970	0.2057	0.077*
C6	0.46144 (13)	0.2201 (3)	0.2374 (3)	0.0641 (7)
H6	0.4974	0.1542	0.2327	0.077*
C12	0.33373 (14)	0.5966 (3)	−0.1997 (2)	0.0684 (7)
H12	0.3722	0.5832	−0.2425	0.082*
C23	0.19815 (13)	0.0763 (3)	0.0553 (2)	0.0766 (8)
H23A	0.1622	0.0292	0.0950	0.115*
H23B	0.2324	0.0053	0.0390	0.115*
H23C	0.1794	0.1190	−0.0200	0.115*
C20	0.02443 (13)	0.3997 (3)	0.3264 (3)	0.0689 (7)
H20	−0.0064	0.4763	0.3324	0.083*
C14	0.23385 (15)	0.7297 (3)	−0.1652 (3)	0.0763 (8)
H14	0.2041	0.8071	−0.1850	0.092*
C22	0.56136 (14)	0.2214 (3)	0.4389 (3)	0.0920 (10)
H22A	0.5343	0.1422	0.4666	0.138*
H22B	0.5963	0.2472	0.5018	0.138*
H22C	0.5824	0.1915	0.3672	0.138*
C13	0.28932 (17)	0.7088 (3)	−0.2310 (3)	0.0769 (8)
H13	0.2967	0.7701	−0.2961	0.092*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0884 (6)	0.0939 (5)	0.1166 (8)	−0.0106 (4)	0.0361 (5)	0.0046 (5)
O1	0.0652 (12)	0.0747 (12)	0.0852 (15)	0.0043 (9)	−0.0190 (11)	0.0003 (10)
N2	0.0594 (13)	0.0641 (12)	0.0614 (15)	0.0122 (10)	0.0035 (11)	0.0200 (11)
N1	0.0532 (12)	0.0553 (12)	0.0565 (14)	0.0051 (9)	−0.0015 (10)	0.0106 (10)
C4	0.0522 (15)	0.0453 (12)	0.0479 (15)	0.0079 (11)	0.0034 (12)	0.0062 (12)
C1	0.0551 (15)	0.0484 (13)	0.0500 (16)	0.0001 (11)	−0.0128 (13)	0.0054 (12)
C10	0.0590 (15)	0.0464 (13)	0.0488 (15)	−0.0071 (12)	−0.0073 (12)	0.0029 (12)
C3	0.0636 (16)	0.0502 (13)	0.0512 (16)	0.0115 (12)	−0.0019 (13)	0.0037 (12)
C8	0.0650 (16)	0.0458 (13)	0.0551 (17)	0.0041 (12)	0.0051 (14)	−0.0022 (12)
C9	0.0563 (15)	0.0461 (13)	0.0590 (17)	0.0119 (11)	0.0043 (13)	0.0005 (13)
C2	0.0613 (16)	0.0498 (13)	0.0515 (16)	0.0065 (12)	−0.0105 (12)	0.0071 (12)
C7	0.0523 (16)	0.0533 (14)	0.0548 (17)	−0.0016 (12)	0.0012 (14)	0.0062 (13)
C18	0.0651 (17)	0.0564 (15)	0.0662 (19)	−0.0136 (13)	−0.0082 (15)	0.0092 (13)
C5	0.0636 (17)	0.0606 (15)	0.0587 (18)	0.0132 (13)	0.0096 (14)	−0.0101 (13)
C19	0.0578 (16)	0.0647 (16)	0.071 (2)	−0.0088 (13)	0.0018 (14)	−0.0002 (15)
C16	0.0539 (15)	0.0495 (13)	0.0508 (16)	−0.0022 (11)	−0.0105 (13)	0.0046 (12)
C17	0.0560 (16)	0.0527 (14)	0.0665 (18)	−0.0021 (12)	−0.0061 (14)	0.0061 (13)
C11	0.0680 (17)	0.0523 (14)	0.0532 (16)	−0.0053 (12)	−0.0051 (13)	−0.0035 (13)
C15	0.0741 (18)	0.0476 (14)	0.074 (2)	−0.0006 (13)	−0.0006 (15)	0.0078 (14)
C21	0.0689 (17)	0.0551 (14)	0.0685 (19)	0.0026 (13)	−0.0013 (15)	0.0117 (14)
C6	0.0515 (16)	0.0656 (16)	0.075 (2)	0.0175 (12)	0.0034 (15)	−0.0051 (15)
C12	0.086 (2)	0.0581 (15)	0.0615 (19)	−0.0192 (15)	0.0115 (15)	−0.0076 (15)
C23	0.0889 (19)	0.0564 (15)	0.081 (2)	0.0011 (14)	−0.0101 (16)	−0.0044 (14)
C20	0.0661 (18)	0.0619 (16)	0.078 (2)	0.0083 (13)	0.0034 (16)	0.0054 (15)
C14	0.094 (2)	0.0478 (15)	0.085 (2)	0.0013 (14)	−0.0043 (18)	0.0201 (16)
C22	0.071 (2)	0.098 (2)	0.103 (3)	0.0150 (17)	−0.0181 (18)	0.0142 (19)
C13	0.109 (2)	0.0524 (16)	0.069 (2)	−0.0153 (16)	0.0058 (18)	0.0062 (15)

Geometric parameters (Å, º) top

Cl1—C19	1.734 (3)	C5—C6	1.370 (3)
O1—C7	1.365 (3)	C5—H5	0.9300
O1—C22	1.402 (3)	C19—C20	1.373 (3)
N2—N1	1.369 (2)	C16—C21	1.382 (3)
N2—C10	1.389 (3)	C16—C17	1.387 (3)
N2—C3	1.469 (3)	C17—H17	0.9300
N1—C1	1.287 (3)	C11—C12	1.383 (3)
C4—C5	1.369 (3)	C11—H11	0.9300
C4—C9	1.386 (3)	C15—C14	1.380 (3)
C4—C3	1.495 (3)	C15—H15	0.9300
C1—C16	1.462 (3)	C21—C20	1.377 (3)
C1—C2	1.506 (3)	C21—H21	0.9300
C10—C11	1.384 (3)	C6—H6	0.9300
C10—C15	1.385 (3)	C12—C13	1.368 (3)
C3—C2	1.541 (3)	C12—H12	0.9300
C3—H3	0.9800	C23—H23A	0.9600
C8—C9	1.366 (3)	C23—H23B	0.9600
C8—C7	1.371 (3)	C23—H23C	0.9600
C8—H8	0.9300	C20—H20	0.9300
C9—H9	0.9300	C14—C13	1.368 (4)
C2—C23	1.527 (3)	C14—H14	0.9300
C2—H2	0.9800	C22—H22A	0.9600
C7—C6	1.365 (3)	C22—H22B	0.9600
C18—C19	1.365 (3)	C22—H22C	0.9600
C18—C17	1.380 (3)	C13—H13	0.9300
C18—H18	0.9300

C7—O1—C22	117.7 (2)	C20—C19—Cl1	119.9 (2)
N1—N2—C10	120.85 (19)	C21—C16—C17	117.4 (2)
N1—N2—C3	112.56 (18)	C21—C16—C1	121.4 (2)
C10—N2—C3	125.8 (2)	C17—C16—C1	121.2 (2)
C1—N1—N2	108.79 (18)	C18—C17—C16	121.5 (2)
C5—C4—C9	117.6 (2)	C18—C17—H17	119.3
C5—C4—C3	120.7 (2)	C16—C17—H17	119.3
C9—C4—C3	121.5 (2)	C12—C11—C10	120.6 (2)
N1—C1—C16	121.2 (2)	C12—C11—H11	119.7
N1—C1—C2	113.4 (2)	C10—C11—H11	119.7
C16—C1—C2	125.4 (2)	C14—C15—C10	120.1 (3)
C11—C10—C15	118.5 (2)	C14—C15—H15	120.0
C11—C10—N2	121.0 (2)	C10—C15—H15	120.0
C15—C10—N2	120.5 (2)	C20—C21—C16	121.5 (2)
N2—C3—C4	112.25 (19)	C20—C21—H21	119.3
N2—C3—C2	101.37 (18)	C16—C21—H21	119.3
C4—C3—C2	113.40 (19)	C7—C6—C5	119.7 (2)
N2—C3—H3	109.8	C7—C6—H6	120.2
C4—C3—H3	109.8	C5—C6—H6	120.2
C2—C3—H3	109.8	C13—C12—C11	120.5 (3)
C9—C8—C7	120.0 (2)	C13—C12—H12	119.7
C9—C8—H8	120.0	C11—C12—H12	119.7
C7—C8—H8	120.0	C2—C23—H23A	109.5
C8—C9—C4	121.0 (2)	C2—C23—H23B	109.5
C8—C9—H9	119.5	H23A—C23—H23B	109.5
C4—C9—H9	119.5	C2—C23—H23C	109.5
C1—C2—C23	112.7 (2)	H23A—C23—H23C	109.5
C1—C2—C3	101.28 (17)	H23B—C23—H23C	109.5
C23—C2—C3	113.2 (2)	C19—C20—C21	119.7 (2)
C1—C2—H2	109.8	C19—C20—H20	120.2
C23—C2—H2	109.8	C21—C20—H20	120.2
C3—C2—H2	109.8	C13—C14—C15	121.2 (3)
C6—C7—O1	124.2 (2)	C13—C14—H14	119.4
C6—C7—C8	119.9 (2)	C15—C14—H14	119.4
O1—C7—C8	115.9 (2)	O1—C22—H22A	109.5
C19—C18—C17	119.6 (2)	O1—C22—H22B	109.5
C19—C18—H18	120.2	H22A—C22—H22B	109.5
C17—C18—H18	120.2	O1—C22—H22C	109.5
C4—C5—C6	121.8 (2)	H22A—C22—H22C	109.5
C4—C5—H5	119.1	H22B—C22—H22C	109.5
C6—C5—H5	119.1	C12—C13—C14	119.1 (3)
C18—C19—C20	120.3 (2)	C12—C13—H13	120.4
C18—C19—Cl1	119.7 (2)	C14—C13—H13	120.4

Hydrogen-bond geometry (Å, º) top

Cg3 and Cg4 are the centroids of the C10–C15 and C16–C21 rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···Cg3ⁱ	0.98	2.98	3.847 (3)	148
C23—H23C···Cg4ⁱⁱ	0.96	2.80	3.679 (3)	153

Symmetry codes: (i) x, −y−1/2, z−1/2; (ii) x, −y−1/2, z−3/2.

Acknowledgements

The authors thank the Unit of Support for Technical and Scientific Research (UATRS, CNRST) for the X-ray measurements.

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