(E)-3-(4-Methyl-phen-yl)-3-[3-(4-methyl-phen-yl)-1H-pyrazol-1-yl]-2-propenal.

In the title compound, C(20)H(18)N(2)O, the pyrazole ring adopts a planar conformation. The C-N bond lengths in the pyrazole ring are shorter than a standard C-N single bond (1.443 Å), but longer than a standard double bond (1.269 Å), indicating electron delocalization. The propenal group assumes an extended conformation. Inter-molecular C-H⋯O hydrogen bonds connect mol-ecules into cyclic centrosymmetric R(2) (2)(26) dimers, which are cross-linked via C-H⋯π inter-actions.

Related literature

For the properties of pyrazole derivatives, see: Baraldi et al. (1998 ▶); Bruno et al. (1990 ▶); Chen & Li (1998 ▶); Cottineau et al. (2002 ▶); Londershausen (1996 ▶); Mishra et al. (1998 ▶); Smith et al. (2001 ▶). For related literature, see: Beddoes et al. (1986 ▶); Jin et al. (2004 ▶); Bernstein et al. (1995 ▶); Cordell (1981 ▶).

Experimental

Crystal data

C20H18N2O

M = 302.36

Triclinic,

a = 10.0560 (9) Å

b = 10.0786 (8) Å

c = 10.3176 (9) Å

α = 62.040 (4)°

β = 79.356 (4)°

γ = 63.038 (4)°

V = 822.73 (12) Å3

Z = 2

Mo Kα radiation

μ = 0.08 mm−1

T = 293 (2) K

0.30 × 0.22 × 0.20 mm

Data collection

Bruker APEXII CCD area-detector diffractometer

Absorption correction: multi-scan (SADABS; Sheldrick, 2001 ▶) T min = 0.980, T max = 0.985

14086 measured reflections

2887 independent reflections

2315 reflections with I > 2σ(I)

R int = 0.035

Refinement

R[F 2 > 2σ(F 2)] = 0.048

wR(F 2) = 0.154

S = 1.03

2887 reflections

210 parameters

H-atom parameters constrained

Δρmax = 0.24 e Å−3

Δρmin = −0.23 e Å−3

Data collection: APEX2 (Bruker, 2004 ▶); cell refinement: APEX2; data reduction: SAINT (Bruker, 2004 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2003 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808034697/gw2051sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808034697/gw2051Isup2.hkl

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

C20H18N2O	Z = 2
Mr = 302.36	F(000) = 320
Triclinic, P1	Dx = 1.221 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 10.0560 (9) Å	Cell parameters from 2865 reflections
b = 10.0786 (8) Å	θ = 2.2–25.0°
c = 10.3176 (9) Å	µ = 0.08 mm−1
α = 62.040 (4)°	T = 293 K
β = 79.356 (4)°	Block, colorless
γ = 63.038 (4)°	0.30 × 0.22 × 0.20 mm
V = 822.73 (12) Å3

Bruker APEXII CCD area-detector diffractometer	2887 independent reflections
Radiation source: fine-focus sealed tube	2315 reflections with I > 2σ(I)
graphite	Rint = 0.035
ω and φ scans	θmax = 25.0°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Sheldrick, 2001)	h = −11→11
Tmin = 0.980, Tmax = 0.985	k = −11→11
14086 measured reflections	l = −12→12

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)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.154	H-atom parameters constrained
S = 1.03	w = 1/[σ2(Fo2) + (0.0885P)2 + 0.2614P] where P = (Fo2 + 2Fc2)/3
2887 reflections	(Δ/σ)max = 0.037
210 parameters	Δρmax = 0.24 e Å−3
0 restraints	Δρmin = −0.23 e Å−3

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

	x	y	z	Uiso*/Ueq
O1	0.67828 (17)	0.53579 (18)	0.72181 (16)	0.0625 (4)
N1	0.60777 (16)	0.58095 (17)	0.26253 (16)	0.0432 (4)
N2	0.68095 (16)	0.41223 (17)	0.31521 (16)	0.0427 (4)
C3	0.69279 (19)	0.3841 (2)	0.19979 (19)	0.0416 (4)
C4	0.6304 (2)	0.5334 (2)	0.0717 (2)	0.0519 (5)
H4	0.6267	0.5457	−0.0229	0.062*
C5	0.5774 (2)	0.6543 (2)	0.1158 (2)	0.0515 (5)
H5	0.5288	0.7675	0.0565	0.062*
C6	0.57725 (18)	0.6542 (2)	0.35731 (19)	0.0400 (4)
C7	0.45725 (19)	0.8246 (2)	0.30619 (18)	0.0396 (4)
C8	0.3162 (2)	0.8596 (2)	0.2667 (2)	0.0450 (4)
H8	0.2986	0.7771	0.2657	0.054*
C9	0.2021 (2)	1.0156 (2)	0.2292 (2)	0.0477 (5)
H9	0.1077	1.0364	0.2051	0.057*
C10	0.2255 (2)	1.1425 (2)	0.2264 (2)	0.0472 (5)
C11	0.3665 (2)	1.1077 (2)	0.2624 (2)	0.0490 (5)
H11	0.3847	1.1916	0.2597	0.059*
C12	0.4818 (2)	0.9513 (2)	0.3023 (2)	0.0451 (4)
H12	0.5759	0.9308	0.3267	0.054*
C13	0.1000 (3)	1.3122 (3)	0.1849 (3)	0.0705 (6)
H13A	0.1319	1.3799	0.2011	0.106*
H13B	0.0158	1.3034	0.2439	0.106*
H13C	0.0719	1.3618	0.0831	0.106*
C14	0.65218 (19)	0.5672 (2)	0.48724 (19)	0.0439 (4)
H14	0.7338	0.4666	0.5039	0.053*
C15	0.6144 (2)	0.6193 (2)	0.6020 (2)	0.0465 (4)
H15	0.5367	0.7228	0.5837	0.056*
C16	0.75914 (19)	0.2135 (2)	0.21612 (19)	0.0431 (4)
C17	0.8059 (2)	0.0785 (2)	0.3526 (2)	0.0541 (5)
H17	0.7965	0.0953	0.4357	0.065*
C18	0.8664 (2)	−0.0813 (3)	0.3660 (2)	0.0600 (5)
H18	0.8978	−0.1702	0.4583	0.072*
C19	0.8812 (2)	−0.1120 (3)	0.2463 (3)	0.0563 (5)
C20	0.8340 (2)	0.0235 (3)	0.1112 (3)	0.0614 (6)
H20	0.8430	0.0064	0.0284	0.074*
C21	0.7740 (2)	0.1837 (3)	0.0956 (2)	0.0548 (5)
H21	0.7432	0.2722	0.0029	0.066*
C22	0.9457 (3)	−0.2851 (3)	0.2607 (3)	0.0817 (8)
H22A	0.9448	−0.3606	0.3615	0.123*
H22B	1.0465	−0.3148	0.2285	0.123*
H22C	0.8869	−0.2905	0.2013	0.123*

	U11	U22	U33	U12	U13	U23
O1	0.0725 (10)	0.0569 (9)	0.0525 (9)	−0.0170 (7)	−0.0167 (7)	−0.0231 (7)
N1	0.0508 (9)	0.0338 (8)	0.0399 (8)	−0.0144 (6)	−0.0021 (6)	−0.0144 (6)
N2	0.0462 (8)	0.0361 (8)	0.0409 (8)	−0.0128 (6)	−0.0014 (6)	−0.0167 (6)
C3	0.0412 (9)	0.0424 (10)	0.0394 (9)	−0.0158 (8)	0.0026 (7)	−0.0187 (8)
C4	0.0643 (12)	0.0491 (11)	0.0379 (10)	−0.0213 (9)	0.0008 (8)	−0.0182 (8)
C5	0.0641 (12)	0.0397 (10)	0.0405 (10)	−0.0178 (9)	−0.0035 (8)	−0.0119 (8)
C6	0.0423 (9)	0.0363 (9)	0.0435 (9)	−0.0187 (8)	0.0016 (7)	−0.0173 (7)
C7	0.0441 (9)	0.0334 (9)	0.0386 (9)	−0.0171 (7)	−0.0002 (7)	−0.0127 (7)
C8	0.0505 (10)	0.0400 (10)	0.0487 (10)	−0.0225 (8)	−0.0043 (8)	−0.0172 (8)
C9	0.0428 (10)	0.0464 (10)	0.0493 (10)	−0.0182 (8)	−0.0047 (8)	−0.0161 (8)
C10	0.0526 (11)	0.0360 (9)	0.0432 (10)	−0.0146 (8)	−0.0030 (8)	−0.0121 (8)
C11	0.0620 (12)	0.0333 (9)	0.0515 (11)	−0.0230 (9)	−0.0056 (9)	−0.0131 (8)
C12	0.0458 (10)	0.0401 (10)	0.0494 (10)	−0.0220 (8)	−0.0037 (8)	−0.0140 (8)
C13	0.0647 (14)	0.0433 (12)	0.0827 (16)	−0.0084 (10)	−0.0120 (11)	−0.0206 (11)
C14	0.0445 (10)	0.0376 (9)	0.0472 (10)	−0.0147 (8)	−0.0026 (8)	−0.0179 (8)
C15	0.0504 (10)	0.0400 (10)	0.0494 (11)	−0.0177 (8)	−0.0057 (8)	−0.0185 (8)
C16	0.0397 (9)	0.0449 (10)	0.0449 (10)	−0.0164 (8)	0.0043 (7)	−0.0224 (8)
C17	0.0643 (12)	0.0479 (11)	0.0458 (11)	−0.0184 (9)	0.0031 (9)	−0.0231 (9)
C18	0.0643 (13)	0.0425 (11)	0.0598 (13)	−0.0175 (10)	0.0041 (10)	−0.0179 (9)
C19	0.0412 (10)	0.0528 (12)	0.0819 (15)	−0.0178 (9)	0.0089 (9)	−0.0391 (11)
C20	0.0588 (12)	0.0667 (14)	0.0698 (14)	−0.0182 (11)	0.0022 (10)	−0.0463 (12)
C21	0.0574 (12)	0.0539 (12)	0.0506 (11)	−0.0145 (9)	−0.0029 (9)	−0.0280 (9)
C22	0.0724 (16)	0.0617 (15)	0.123 (2)	−0.0251 (12)	0.0162 (15)	−0.0569 (16)

O1—C15	1.215 (2)	C12—H12	0.9300
N1—C5	1.360 (2)	C13—H13A	0.9600
N1—N2	1.369 (2)	C13—H13B	0.9600
N1—C6	1.399 (2)	C13—H13C	0.9600
N2—C3	1.321 (2)	C14—C15	1.435 (3)
C3—C4	1.411 (3)	C14—H14	0.9300
C3—C16	1.469 (2)	C15—H15	0.9300
C4—C5	1.348 (3)	C16—C21	1.379 (3)
C4—H4	0.9300	C16—C17	1.387 (3)
C5—H5	0.9300	C17—C18	1.384 (3)
C6—C14	1.344 (2)	C17—H17	0.9300
C6—C7	1.480 (2)	C18—C19	1.375 (3)
C7—C12	1.388 (2)	C18—H18	0.9300
C7—C8	1.388 (2)	C19—C20	1.380 (3)
C8—C9	1.377 (3)	C19—C22	1.501 (3)
C8—H8	0.9300	C20—C21	1.380 (3)
C9—C10	1.388 (3)	C20—H20	0.9300
C9—H9	0.9300	C21—H21	0.9300
C10—C11	1.376 (3)	C22—H22A	0.9600
C10—C13	1.503 (3)	C22—H22B	0.9600
C11—C12	1.382 (3)	C22—H22C	0.9600
C11—H11	0.9300
C5—N1—N2	110.87 (14)	C10—C13—H13B	109.5
C5—N1—C6	129.15 (15)	H13A—C13—H13B	109.5
N2—N1—C6	119.97 (14)	C10—C13—H13C	109.5
C3—N2—N1	104.85 (14)	H13A—C13—H13C	109.5
N2—C3—C4	111.37 (16)	H13B—C13—H13C	109.5
N2—C3—C16	120.39 (16)	C6—C14—C15	124.24 (16)
C4—C3—C16	128.20 (16)	C6—C14—H14	117.9
C5—C4—C3	105.21 (17)	C15—C14—H14	117.9
C5—C4—H4	127.4	O1—C15—C14	123.68 (17)
C3—C4—H4	127.4	O1—C15—H15	118.2
C4—C5—N1	107.70 (16)	C14—C15—H15	118.2
C4—C5—H5	126.2	C21—C16—C17	118.12 (17)
N1—C5—H5	126.2	C21—C16—C3	120.56 (17)
C14—C6—N1	119.58 (15)	C17—C16—C3	121.31 (16)
C14—C6—C7	124.72 (15)	C18—C17—C16	120.45 (19)
N1—C6—C7	115.65 (14)	C18—C17—H17	119.8
C12—C7—C8	118.61 (16)	C16—C17—H17	119.8
C12—C7—C6	120.61 (15)	C19—C18—C17	121.7 (2)
C8—C7—C6	120.73 (15)	C19—C18—H18	119.1
C9—C8—C7	120.48 (16)	C17—C18—H18	119.1
C9—C8—H8	119.8	C18—C19—C20	117.22 (19)
C7—C8—H8	119.8	C18—C19—C22	121.8 (2)
C8—C9—C10	121.20 (17)	C20—C19—C22	120.9 (2)
C8—C9—H9	119.4	C19—C20—C21	121.90 (19)
C10—C9—H9	119.4	C19—C20—H20	119.1
C11—C10—C9	117.95 (17)	C21—C20—H20	119.1
C11—C10—C13	121.45 (18)	C16—C21—C20	120.6 (2)
C9—C10—C13	120.60 (18)	C16—C21—H21	119.7
C10—C11—C12	121.59 (17)	C20—C21—H21	119.7
C10—C11—H11	119.2	C19—C22—H22A	109.5
C12—C11—H11	119.2	C19—C22—H22B	109.5
C11—C12—C7	120.15 (16)	H22A—C22—H22B	109.5
C11—C12—H12	119.9	C19—C22—H22C	109.5
C7—C12—H12	119.9	H22A—C22—H22C	109.5
C10—C13—H13A	109.5	H22B—C22—H22C	109.5
C5—N1—N2—C3	−0.79 (19)	C9—C10—C11—C12	−1.0 (3)
C6—N1—N2—C3	−179.57 (15)	C13—C10—C11—C12	179.22 (19)
N1—N2—C3—C4	1.1 (2)	C10—C11—C12—C7	0.4 (3)
N1—N2—C3—C16	−176.65 (15)	C8—C7—C12—C11	1.1 (3)
N2—C3—C4—C5	−1.1 (2)	C6—C7—C12—C11	−176.32 (16)
C16—C3—C4—C5	176.50 (18)	N1—C6—C14—C15	−169.74 (16)
C3—C4—C5—N1	0.5 (2)	C7—C6—C14—C15	7.8 (3)
N2—N1—C5—C4	0.1 (2)	C6—C14—C15—O1	176.16 (18)
C6—N1—C5—C4	178.78 (17)	N2—C3—C16—C21	−178.92 (17)
C5—N1—C6—C14	−160.85 (19)	C4—C3—C16—C21	3.7 (3)
N2—N1—C6—C14	17.7 (2)	N2—C3—C16—C17	2.4 (3)
C5—N1—C6—C7	21.4 (3)	C4—C3—C16—C17	−175.02 (19)
N2—N1—C6—C7	−160.09 (14)	C21—C16—C17—C18	0.4 (3)
C14—C6—C7—C12	54.5 (2)	C3—C16—C17—C18	179.17 (18)
N1—C6—C7—C12	−127.83 (17)	C16—C17—C18—C19	−0.5 (3)
C14—C6—C7—C8	−122.9 (2)	C17—C18—C19—C20	0.4 (3)
N1—C6—C7—C8	54.8 (2)	C17—C18—C19—C22	−179.5 (2)
C12—C7—C8—C9	−2.0 (3)	C18—C19—C20—C21	−0.1 (3)
C6—C7—C8—C9	175.42 (16)	C22—C19—C20—C21	179.7 (2)
C7—C8—C9—C10	1.4 (3)	C17—C16—C21—C20	−0.2 (3)
C8—C9—C10—C11	0.1 (3)	C3—C16—C21—C20	−178.93 (17)
C8—C9—C10—C13	179.87 (19)	C19—C20—C21—C16	0.0 (3)

D—H···A	D—H	H···A	D···A	D—H···A
C22—H22B···O1i	0.96	2.60	3.446 (3)	148
C9—H9···Cg1ii	0.93	2.80	3.690 (3)	161

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C22—H22B⋯O1i	0.96	2.60	3.446 (3)	148
C9—H9⋯Cg1ii	0.93	2.80	3.690 (3)	161

Symmetry codes: (i) ; (ii) . Cg1 is the centroid of the C16–C21 ring.