6-Methyl-2-phenyl-4,5-dihydro­pyridazin-3(2H)-one

Abstract

In the title mol­ecule, C₁₁H₁₂N₂O, the pyridazine ring has a skew-boat conformation. The dihedral angle between the phenyl ring [r.m.s deviation = 0.0039 (15) Å] and the best mean-plane of the pyridazine ring [r.m.s deviations = 0.2629 (15) Å] is 53.27 (10)°. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds and C—H⋯π inter­actions involving the methyl group and the phenyl ring of a symmetry-related mol­ecule.

Related literature

For the similar structure, 2-(4-meth­oxy­phen­yl)-6-(trifluoro­meth­yl)-4,5-dihydro­pyridazin-3(2H)-one, see: Wan et al. (2009 ▶). For conformation analysis of six-membered rings, see: Cremer & Pople (1975 ▶).

Experimental

Crystal data

• C₁₁H₁₂N₂O

• M _r = 188.23

• Monoclinic,

• a = 6.4151 (2) Å

• b = 7.9010 (2) Å

• c = 10.1888 (3) Å

• β = 106.607 (1)°

• V = 494.89 (2) ų

• Z = 2

• Mo Kα radiation

• μ = 0.08 mm⁻¹

• T = 296 K

• 0.24 × 0.15 × 0.12 mm

Data collection

• Bruker APEXII CCD detector diffractometer

• 7678 measured reflections

• 1220 independent reflections

• 1154 reflections with I > 2σ(I)

• R _int = 0.031

Refinement

• R[F ² > 2σ(F ²)] = 0.032

• wR(F ²) = 0.094

• S = 1.06

• 1220 reflections

• 129 parameters

• 1 restraint

• H-atom parameters constrained

• Δρ_max = 0.15 e Å⁻³

• Δρ_min = −0.13 e Å⁻³

Data collection: APEX2 (Bruker, 2005 ▶); cell refinement: SAINT (Bruker, 2005 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: PLATON (Spek, 2009 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Supplementary Material

Supplementary material file. DOI: 10.1107/S1600536811021970/su2275Isup3.cml

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

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

Cg1 is the centroid of the C1–C6 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C3—H3⋯O1i	0.93	2.54	3.371 (3)	149
C5—H5⋯O1ii	0.93	2.50	3.346 (2)	152
C8—H8B⋯O1iii	0.97	2.55	3.474 (3)	159
C11—H11B⋯Cg1iv	0.96	2.89	3.812 (3)	161

Symmetry codes: (i) ; (ii) ; (iii) ; (iv) .

supplementary crystallographic information

Comment

The molecular structure of the title molecule is illustrated in Fig. 1. The bond distances and angles are simliar to those reported for 2-(4-Methoxyphenyl)-6-(trifluoromethyl)-4,5-dihydropyridazin-3(2H)-one (Wan et al., 2009). The pyridazine ring has a skew-boat conformation; Puckering Amplitude (Q) = 0.428 (2) Å, θ = 69.9 (2)°, φ = 207.6 (3) ° (Cremer and Pople, 1975). The dihedral angle between the phenyl ring and the best mean-plane of the pyridazine ring (r.m.s deviations: 0.2629 (15) Å) is 53.27 (10)°.

In the crystal molecules are linked via non-classical C—H···O hydrogen bonds (Table 1), forming a two-dimensional network (Fig. 2). Molecules are also linked by C—H···π interactions involving a methyl H-atom and the phenyl ring of a symmetry related molecule (Table 1).

Experimental

A mixture of phenylhydrazine (2.7 ml, 27 mmol) and levulinic acid (2.6 ml, 25 mmol) in 60 ml of ethanol were refluxed for 4 h. After cooling the reaction mixture was poured onto ice. The solid obtained was filtered off and recrystallized from methanol to give the title compound as colourless crystals: Yield 3.9 g (85%); Mp: 367–369 K. Spectroscopic data for the title compound is given in the archived CIF.

Refinement

In the final cycles of refinement, in the absence of significant anomalous scattering effects, 906 Friedel pairs were merged and Δf " set to zero. H-atoms were positioned geometrically, with C–H = 0.93 Å for CH(aromatic), 0.97 Å for CH₂ and 0.96 Å for CH₃ H-atoms. They were constrained to ride on their parent atoms, with U_iso(H) = k × U_eq(C), where k = 1.5 for CH₃ H-atoms and k = 1.2 for all other H-atoms.

Figures

Fig. 1.

A view of the molecular structure of the title molecule, showing the atom-labeling scheme. Displacement ellipsoids are drawn at the 50% probability level.

Fig. 2.

A view along the b axis of the crystal packing of the title compound, showing the chain formed by C—H···O interactions (dashed lines; see Table 1 for details). H-atoms not involved in hydrogen bonding have been omitted for clarity.

Crystal data

C11H12N2O	F(000) = 200
Mr = 188.23	Dx = 1.263 Mg m−3
Monoclinic, P21	Melting point: 397 K
Hall symbol: P 2yb	Mo Kα radiation, λ = 0.71073 Å
a = 6.4151 (2) Å	Cell parameters from 256 reflections
b = 7.9010 (2) Å	θ = 2.4–26.5°
c = 10.1888 (3) Å	µ = 0.08 mm−1
β = 106.607 (1)°	T = 296 K
V = 494.89 (2) Å3	Prism, colourless
Z = 2	0.24 × 0.15 × 0.12 mm

Data collection

Bruker APEXII CCD detector diffractometer	1154 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.031
graphite	θmax = 27.5°, θmin = 2.1°
ω and φ scans	h = −8→7
7678 measured reflections	k = −8→10
1220 independent reflections	l = −12→13

Refinement

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.032	H-atom parameters constrained
wR(F2) = 0.094	w = 1/[σ2(Fo2) + (0.0582P)2 + 0.0443P] where P = (Fo2 + 2Fc2)/3
S = 1.06	(Δ/σ)max < 0.001
1220 reflections	Δρmax = 0.15 e Å−3
129 parameters	Δρmin = −0.13 e Å−3
1 restraint	Extinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.21 (2)

Special details

Experimental. Spectroscopic data for the title compound: 1H-NMR (CDCl3): δ 2.14 (s, 3H, CH3), 2.54–2.65 (m, 4H, –CH2—CH2-), 7.20–7.31 (m, 2H, H—Ar), 7.36–7–40 (m, 1H, H—Ar), 7.48–7.51 (m, 2H, H—Ar); 13C-NMR (CDCl3): δ 23.2 (CH3), 26.3 (CH2), 27.7 (CH2), 125 (2CH-Ar), 126.5 (CH—Ar), 128.6 (2CH-Ar), 141.1, 154 (2 C), 165 (C═O).

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
C1	0.4300 (3)	0.0477 (3)	0.83092 (17)	0.0488 (5)
C10	0.4122 (2)	0.2873 (2)	0.59455 (17)	0.0413 (4)
C11	−0.1543 (3)	0.1310 (3)	0.2779 (2)	0.0598 (6)
C2	0.4258 (4)	−0.0098 (3)	0.95947 (18)	0.0608 (6)
C3	0.2448 (4)	0.0173 (4)	1.00372 (19)	0.0673 (7)
C4	0.0679 (4)	0.1005 (4)	0.92101 (19)	0.0652 (6)
C5	0.0682 (3)	0.1580 (3)	0.79218 (17)	0.0488 (4)
C6	0.2502 (3)	0.1303 (2)	0.74779 (15)	0.0389 (4)
C7	0.0504 (3)	0.1740 (2)	0.38723 (16)	0.0416 (4)
C8	0.2420 (3)	0.2321 (3)	0.34560 (17)	0.0513 (4)
C9	0.3773 (3)	0.3520 (3)	0.45107 (18)	0.0527 (5)
H1	0.5527	0.0307	0.8012	0.059*
H11A	−0.1265	0.0394	0.2233	0.090*
H11B	−0.2028	0.2282	0.2207	0.090*
H11C	−0.2646	0.0979	0.3195	0.090*
H2	0.5454	−0.0666	1.0154	0.073*
H3	0.2425	−0.0207	1.0897	0.081*
H4	−0.0537	0.1187	0.9516	0.078*
H5	−0.0522	0.2143	0.7365	0.059*
H8A	0.1937	0.2887	0.2576	0.062*
H8B	0.3295	0.1353	0.3359	0.062*
H9A	0.5173	0.3679	0.4341	0.063*
H9B	0.3053	0.4611	0.4420	0.063*
N1	0.25017 (19)	0.18561 (19)	0.61361 (12)	0.0389 (3)
N2	0.0518 (2)	0.1529 (2)	0.51137 (14)	0.0434 (4)
O1	0.5696 (2)	0.3270 (2)	0.68880 (14)	0.0560 (4)

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
C1	0.0539 (9)	0.0478 (11)	0.0389 (8)	0.0057 (8)	0.0038 (7)	−0.0021 (8)
C10	0.0413 (7)	0.0409 (9)	0.0420 (8)	−0.0027 (7)	0.0125 (6)	−0.0036 (7)
C11	0.0667 (12)	0.0614 (14)	0.0393 (9)	−0.0110 (11)	−0.0044 (8)	0.0058 (9)
C2	0.0803 (13)	0.0507 (11)	0.0362 (8)	0.0005 (11)	−0.0081 (8)	0.0020 (9)
C3	0.0981 (17)	0.0708 (15)	0.0300 (7)	−0.0190 (14)	0.0136 (9)	0.0020 (9)
C4	0.0708 (12)	0.0870 (17)	0.0420 (9)	−0.0164 (12)	0.0230 (9)	−0.0045 (11)
C5	0.0465 (8)	0.0620 (11)	0.0374 (8)	−0.0036 (9)	0.0112 (6)	0.0008 (8)
C6	0.0448 (8)	0.0387 (8)	0.0301 (7)	−0.0042 (7)	0.0056 (6)	−0.0015 (6)
C7	0.0499 (8)	0.0360 (8)	0.0346 (7)	−0.0007 (7)	0.0048 (6)	0.0022 (7)
C8	0.0625 (10)	0.0570 (11)	0.0352 (7)	−0.0039 (9)	0.0151 (7)	0.0019 (8)
C9	0.0579 (10)	0.0550 (11)	0.0474 (9)	−0.0115 (9)	0.0189 (8)	0.0028 (9)
N1	0.0390 (6)	0.0451 (8)	0.0306 (6)	−0.0027 (6)	0.0067 (5)	0.0004 (6)
N2	0.0416 (7)	0.0494 (9)	0.0342 (6)	−0.0062 (7)	0.0027 (5)	0.0034 (6)
O1	0.0454 (6)	0.0631 (9)	0.0533 (7)	−0.0136 (7)	0.0044 (5)	−0.0029 (7)

Geometric parameters (Å, °)

C1—H1	0.9300	C5—C4	1.389 (3)
C1—C2	1.394 (3)	C6—N1	1.4351 (19)
C10—C9	1.504 (2)	C6—C5	1.385 (2)
C10—N1	1.371 (2)	C6—C1	1.384 (2)
C10—O1	1.219 (2)	C7—C11	1.498 (2)
C11—H11C	0.9600	C7—C8	1.483 (2)
C11—H11B	0.9600	C7—N2	1.273 (2)
C11—H11A	0.9600	C8—H8B	0.9700
C2—H2	0.9300	C8—H8A	0.9700
C2—C3	1.377 (4)	C9—H9B	0.9700
C3—H3	0.9300	C9—H9A	0.9700
C3—C4	1.373 (4)	C9—C8	1.507 (3)
C4—H4	0.9300	N2—N1	1.4191 (17)
C5—H5	0.9300
C2—C1—H1	120.2	C6—C5—C4	119.07 (19)
C6—C1—H1	120.2	C5—C6—N1	119.50 (15)
C6—C1—C2	119.50 (19)	C1—C6—N1	119.99 (15)
N1—C10—C9	115.39 (14)	C1—C6—C5	120.50 (15)
O1—C10—C9	122.55 (16)	C8—C7—C11	118.64 (15)
O1—C10—N1	122.02 (16)	N2—C7—C11	117.69 (17)
H11B—C11—H11C	109.5	N2—C7—C8	123.63 (14)
H11A—C11—H11C	109.5	H8A—C8—H8B	108.1
C7—C11—H11C	109.5	C9—C8—H8B	109.6
H11A—C11—H11B	109.5	C7—C8—H8B	109.6
C7—C11—H11B	109.5	C9—C8—H8A	109.6
C7—C11—H11A	109.5	C7—C8—H8A	109.6
C1—C2—H2	120.0	C7—C8—C9	110.26 (15)
C3—C2—H2	120.0	H9A—C9—H9B	107.9
C3—C2—C1	120.08 (19)	C8—C9—H9B	109.2
C2—C3—H3	120.0	C10—C9—H9B	109.2
C4—C3—H3	120.0	C8—C9—H9A	109.2
C4—C3—C2	120.02 (17)	C10—C9—H9A	109.2
C5—C4—H4	119.6	C10—C9—C8	112.02 (17)
C3—C4—H4	119.6	N2—N1—C6	113.57 (12)
C3—C4—C5	120.8 (2)	C10—N1—C6	121.30 (13)
C4—C5—H5	120.5	C10—N1—N2	124.06 (13)
C6—C5—H5	120.5	C7—N2—N1	117.09 (14)

Hydrogen-bond geometry (Å, °)

Cg1 is the centroid of the C1–C6 ring.

D—H···A	D—H	H···A	D···A	D—H···A
C3—H3···O1i	0.93	2.54	3.371 (3)	149
C5—H5···O1ii	0.93	2.50	3.346 (2)	152
C8—H8B···O1iii	0.97	2.55	3.474 (3)	159
C11—H11B···Cg1iv	0.96	2.89	3.812 (3)	161

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