2,3-Di­methyl­quinazolin-4(3H)-one

The non-H atoms of the title mol­ecule, C₁₀H₁₀N₂O, are essentially coplanar, with a maximum deviation of 0.046 (4) Å for the O atom. In the crystal, mol­ecules are linked by weak C—H...O hydrogen bonds, forming chains along [010]. In addtion, weak C—H...π inter­actions and π–π stacking inter­actions between benzene and pyrimidine rings, with a centroid–centroid distance of 3.730 (3) Å, link the chains, forming a two-dimensional network parallel to (001).

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.008 Å
• R factor = 0.071
• wR factor = 0.230
• Data-to-parameter ratio = 13.1

checkCIF/PLATON results

No syntax errors found



Alert level C
STRVA01_ALERT_4_C           Flack parameter is too small
           From the CIF: _refine_ls_abs_structure_Flack   -0.300
           From the CIF: _refine_ls_abs_structure_Flack_su    1.200
PLAT340_ALERT_3_C Low Bond Precision on  C-C Bonds ...............     0.0075 Ang.
PLAT906_ALERT_3_C Large K value in the Analysis of Variance ......      5.504 Check
PLAT911_ALERT_3_C Missing # FCF Refl Between THmin & STh/L=  0.600          4 Why ?
PLAT915_ALERT_3_C Low Friedel Pair Coverage ......................         70 %

Alert level G
PLAT005_ALERT_5_G No _iucr_refine_instructions_details  in the CIF     Please Do !
PLAT032_ALERT_4_G Std. Uncertainty on Flack Parameter Value High .      1.200 Why ?
PLAT072_ALERT_2_G SHELXL First  Parameter in WGHT Unusually Large.       0.11 Why ?
PLAT152_ALERT_1_G The Supplied and Calc. Volume s.u. Differ by ...         -5 Units
PLAT199_ALERT_1_G Reported _cell_measurement_temperature ..... (K)        293 Check
PLAT200_ALERT_1_G Reported   _diffrn_ambient_temperature ..... (K)        293 Check
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600         19 Note

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   5 ALERT level C = Check. Ensure it is not caused by an omission or oversight
   7 ALERT level G = General information/check it is not something unexpected

   3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   3 ALERT type 4 Improvement, methodology, query or suggestion
   1 ALERT type 5 Informative message, check

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S1. Comment

The molecular structure of the title compound is shown in Fig .1. The non-H atoms are essentially co-planar, with a maximum deviation of 0.046 (4) Å for atom O1. In the crystal, molecules are linked by weak C—H···O hydrogen bonds to form chains along [010] (Fig. 2). In addition, weak C—H···π interactions and π–π stacking interactions between benzene and pyrimidine rings with a centroid–centroid distance of 3.730 (3)Å, link chains forming a two-dimensional network parallel to (001). The bond distances (Allen et al., 1987) and angles are in normal ranges. The crystal structure of a related cation is reported in the literature (Makhloufi et al., 2013) and the synthesis of compounds related to the title compound is described by (Takeuchi & Eguchi, 1989).

Related literature

For the synthesis of related compounds, see: Takeuchi & Eguchi (1989). For the crystal structure of a related compound, see: Makhloufi et al. (2013). For standard bond lengths, see: Allen et al. (1987).

S2. Experimental

2-Methylquinazolin-4-one (0.01) mol was disolved in 45 ml absolute ethanol, then 2.5 mmol of NaH was added and then shaken for 30 min. To the reaction mixture was added solution of 0.01 mol methyliodide in 5 ml ethanol and the reaction mixture was refluxed for 4 h at 363 K. To this mixture was added 100 ml of cold water and then extracted with chloroform. The title compound was obtained in 69% yield with m.p. 491 K. Crystals suitable for X-ray analysis were obtained by slow evaporation of a solution of the title compound in ethanol.

S3. Refinement

Carbon-bound H atoms were placed geometrically and treated as riding on their parent atoms, with C—H distances of 0.93 Å (aromatic) and 0.96 Å (methyl) and were refined with U_iso(H)=1.2U_eq(C) for aromatic and U_iso(H)=1.5U_eq(C) for methyl H atoms.

Computing details

Data collection: CrysAlis PRO (Oxford Diffraction, 2009); cell refinement: CrysAlis PRO (Oxford Diffraction, 2009); data reduction: CrysAlis PRO (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

	Fig. 1. The molecular structure of the title compound with displacement ellipsoids are drawn at the 50% probability level.
	Fig. 2. Crystal packing of the title compound showing a hydrogen bonds as dashed lines.

2,3-Dimethylquinazolin-4(3H)-one

Crystal data

C10H10N2O	Dx = 1.313 Mg m^−3
Mr = 174.20	Melting point: 491(2) K
Orthorhombic, P212121	Cu Kα radiation, λ = 1.54184 Å
Hall symbol: P 2ac 2ab	Cell parameters from 333 reflections
a = 4.826 (2) Å	θ = 3.8–64.0°
b = 7.919 (3) Å	µ = 0.71 mm^−1
c = 23.060 (8) Å	T = 293 K
V = 881.3 (11) Å^3	Needle, colourless
Z = 4	0.40 × 0.10 × 0.08 mm
F(000) = 368

Data collection

Oxford Diffraction Xcalibur Ruby diffractometer	1585 independent reflections
Radiation source: fine-focus sealed tube	821 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.020
Detector resolution: 10.2576 pixels mm^-1	θmax = 75.9°, θmin = 3.8°
ω scans	h = −5→5
Absorption correction: multi-scan (CrysAlis PRO; Oxford Diffraction, 2009)	k = −5→9
Tmin = 0.041, Tmax = 1.000	l = −28→28
2236 measured reflections

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.071	H-atom parameters constrained
wR(F^2) = 0.230	w = 1/[σ^2(Fo^2) + (0.1116P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 0.97	(Δ/σ)max < 0.001
1585 reflections	Δρmax = 0.20 e Å^−3
121 parameters	Δρmin = −0.19 e Å^−3
0 restraints	Absolute structure: Flack (1983), 507 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: −0.3 (12)

Special details

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
N3	0.3333 (9)	−0.1245 (5)	0.17512 (17)	0.0819 (12)
O1	0.4020 (9)	0.1511 (4)	0.19869 (17)	0.1055 (13)
N1	0.5799 (9)	−0.2643 (5)	0.10074 (17)	0.0846 (11)
C4A	0.6580 (10)	0.0357 (6)	0.1199 (2)	0.0773 (13)
C4	0.4620 (11)	0.0295 (7)	0.1667 (2)	0.0807 (13)
C10	0.1309 (12)	−0.1350 (7)	0.2233 (2)	0.1009 (17)
H10A	0.2040	−0.2059	0.2534	0.151*
H10B	−0.0397	−0.1819	0.2093	0.151*
H10C	0.0975	−0.0240	0.2386	0.151*
C8	0.8983 (11)	−0.1088 (7)	0.0431 (2)	0.0912 (15)
H8	0.9313	−0.2067	0.0219	0.109*
C2	0.4000 (11)	−0.2650 (6)	0.1422 (2)	0.0816 (13)
C8A	0.7099 (9)	−0.1120 (6)	0.0883 (2)	0.0769 (12)
C7	1.0368 (13)	0.0367 (8)	0.0292 (2)	0.1023 (16)
H7	1.1647	0.0374	−0.0010	0.123*
C9	0.2541 (14)	−0.4274 (7)	0.1551 (3)	0.109 (2)
H9A	0.2779	−0.4552	0.1954	0.164*
H9B	0.3305	−0.5158	0.1316	0.164*
H9C	0.0603	−0.4153	0.1468	0.164*
C6	0.9842 (12)	0.1838 (7)	0.0607 (3)	0.1019 (18)
H6	1.0776	0.2828	0.0514	0.122*
C5	0.7965 (12)	0.1837 (6)	0.1051 (2)	0.0923 (16)
H5	0.7615	0.2828	0.1255	0.111*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N3	0.077 (2)	0.080 (3)	0.089 (3)	0.004 (2)	0.003 (2)	0.002 (2)
O1	0.118 (3)	0.083 (2)	0.115 (3)	0.008 (2)	−0.002 (3)	−0.024 (2)
N1	0.080 (2)	0.080 (2)	0.094 (3)	−0.004 (2)	0.002 (2)	−0.005 (2)
C4A	0.074 (3)	0.072 (3)	0.086 (3)	−0.001 (2)	−0.011 (3)	−0.001 (3)
C4	0.083 (3)	0.073 (3)	0.086 (3)	0.010 (3)	−0.011 (3)	−0.004 (3)
C10	0.100 (4)	0.104 (4)	0.098 (3)	0.020 (4)	0.012 (3)	0.008 (3)
C8	0.085 (3)	0.090 (3)	0.099 (3)	0.004 (3)	0.003 (3)	−0.012 (3)
C2	0.076 (3)	0.066 (3)	0.102 (3)	0.004 (3)	−0.006 (3)	−0.002 (3)
C8A	0.068 (3)	0.071 (3)	0.091 (3)	−0.001 (3)	−0.005 (3)	0.003 (3)
C7	0.092 (4)	0.117 (4)	0.098 (3)	−0.003 (4)	0.006 (3)	0.006 (4)
C9	0.103 (4)	0.077 (3)	0.147 (5)	−0.002 (3)	0.014 (4)	0.002 (4)
C6	0.096 (4)	0.092 (4)	0.118 (4)	−0.013 (3)	−0.008 (4)	0.022 (3)
C5	0.093 (4)	0.076 (3)	0.108 (4)	0.003 (3)	−0.009 (3)	−0.002 (3)

Geometric parameters (Å, º)

N3—C4	1.382 (6)	C8—C7	1.370 (7)
N3—C2	1.385 (6)	C8—C8A	1.383 (7)
N3—C10	1.482 (6)	C8—H8	0.9300
O1—C4	1.248 (6)	C2—C9	1.496 (7)
N1—C2	1.292 (6)	C7—C6	1.397 (8)
N1—C8A	1.390 (6)	C7—H7	0.9300
C4A—C5	1.392 (7)	C9—H9A	0.9600
C4A—C8A	1.400 (6)	C9—H9B	0.9600
C4A—C4	1.436 (7)	C9—H9C	0.9600
C10—H10A	0.9600	C6—C5	1.368 (7)
C10—H10B	0.9600	C6—H6	0.9300
C10—H10C	0.9600	C5—H5	0.9300
C4—N3—C2	121.8 (4)	N1—C2—C9	117.9 (5)
C4—N3—C10	116.8 (4)	N3—C2—C9	118.2 (5)
C2—N3—C10	121.3 (5)	C8—C8A—N1	117.9 (5)
C2—N1—C8A	117.4 (4)	C8—C8A—C4A	119.6 (5)
C5—C4A—C8A	119.4 (5)	N1—C8A—C4A	122.4 (4)
C5—C4A—C4	121.9 (5)	C8—C7—C6	119.4 (5)
C8A—C4A—C4	118.7 (5)	C8—C7—H7	120.3
O1—C4—N3	119.5 (5)	C6—C7—H7	120.3
O1—C4—C4A	124.9 (5)	C2—C9—H9A	109.5
N3—C4—C4A	115.6 (4)	C2—C9—H9B	109.5
N3—C10—H10A	109.5	H9A—C9—H9B	109.5
N3—C10—H10B	109.5	C2—C9—H9C	109.5
H10A—C10—H10B	109.5	H9A—C9—H9C	109.5
N3—C10—H10C	109.5	H9B—C9—H9C	109.5
H10A—C10—H10C	109.5	C5—C6—C7	120.7 (5)
H10B—C10—H10C	109.5	C5—C6—H6	119.7
C7—C8—C8A	120.8 (5)	C7—C6—H6	119.7
C7—C8—H8	119.6	C6—C5—C4A	120.1 (5)
C8A—C8—H8	119.6	C6—C5—H5	120.0
N1—C2—N3	124.0 (5)	C4A—C5—H5	120.0

Hydrogen-bond geometry (Å, º)

Cg is the centroid of the N1/C2/N3/C4/C4A/C8A ring.

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10A···O1^i	0.96	2.47	3.345 (8)	151
C10—H10B···Cg^ii	0.96	2.80	3.608 (6)	142

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