5-Acetyl-4-(4-methoxy­phen­yl)-6-methyl-3,4-dihydro­pyrimidin-2(1H)-one

Chitra, S.; Pandiarajan, K.; Anuradha, N.; Thiruvalluvar, A.

doi:10.1107/S1600536808040270

organic compounds

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ISSN: 2056-9890

Volume 65| Part 1| January 2009| Page o23

doi:10.1107/S1600536808040270

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5-Acetyl-4-(4-methoxyphenyl)-6-methyl-3,4-dihydropyrimidin-2(1H)-one

S. Chitra,^a K. Pandiarajan,^a N. Anuradha ^b and A. Thiruvalluvar ^b ^*

^aDepartment of Chemistry, Annamalai University, Annamalai Nagar 608 002, Tamilnadu, India, and ^bPG Research Department of Physics, Rajah Serfoji Government College (Autonomous), Thanjavur 613 005, Tamil Nadu, India
^*Correspondence e-mail: athiru@vsnl.net

(Received 27 November 2008; accepted 30 November 2008; online 6 December 2008)

In the title molecule, C₁₄H₁₆N₂O₃, the heterocyclic ring adopts a flattened boat conformation, and the plane through its four coplanar atoms makes a dihedral angle of 89.65 (7)° with the benzene ring. The non-H atoms of the carbonyl, acetyl and methyl groups are nearly coplanar with the attached heterocyclic ring. Intermolecular N—H⋯O and C—H⋯O hydrogen bonds are present in the crystal structure.

Related literature

For chemical and medicinal background, see: Atwal et al. (1989 ); Ghorab et al. (2000 ); Kappe (1993 , 2000 ); Kappe et al. (1997 , 2000 ); Shivarama Holla et al. (2004 ); Stefani et al. (2006 ).

Experimental

Crystal data

C₁₄H₁₆N₂O₃
M_r = 260.29
Monoclinic, C 2/c
a = 23.7948 (12) Å
b = 7.9905 (3) Å
c = 14.4757 (7) Å
β = 108.305 (5)°
V = 2613.0 (2) Å³
Z = 8
Mo Kα radiation
μ = 0.09 mm⁻¹
T = 293 (2) K
0.3 × 0.2 × 0.2 mm

Data collection

Bruker Kappa APEXII CCD diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ) T_min = 0.837, T_max = 1.000 (expected range = 0.821–0.981)
26518 measured reflections
2960 independent reflections
2226 reflections with I > 2σ(I)
R_int = 0.045

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.149
S = 1.10
2960 reflections
183 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.24 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O15ⁱ	0.91 (2)	2.01 (2)	2.9209 (18)	172 (2)
N3—H3⋯O2ⁱⁱ	0.89 (2)	2.04 (2)	2.917 (2)	170.3 (19)
C16—H16B⋯O2ⁱⁱⁱ	0.96	2.49	3.425 (3)	165
C61—H61B⋯O15ⁱ	0.96	2.51	3.352 (2)	146
Symmetry codes: (i) $[x, -y+2, z-{\script{1\over 2}}]$ ; (ii) -x, -y+1, -z; (iii) -x, -y+2, -z.

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-NT (Bruker, 2004); data reduction: SAINT-NT; 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: PLATON (Spek, 2003 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536808040270/hb2869sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536808040270/hb2869Isup2.hkl

checkCIF report

Comment top

Dihydropyrimidinone derivatives exhibit a wide range of biological effects including antifungal, antiviral, anticancer, antibacterial, anti-inflammatory and antihypertensive effects (Kappe, 2000; Ghorab et al., 2000; Shivarama Holla et al., 2004). It also exhibit a biological activity of antitumour property (Kappe, 1993). Dihydropyrimidinones used as an anticancer drug capable of inhibiting Kinesin motor protein (Kappe et al., 2000). Many dihydropyrimidinones and their derivatives are pharmacologically important as calcium channel blockers, antihypertensive agents and α-1a-antagonists (Atwal et al., 1989; Kappe et al., 1997). Dihydropyrimidin-2(1H)-ones can be used as an antioxidant agents (Stefani et al., 2006).

In the title molecule, (I) (Fig. 1), the heterocyclic ring adopts a flattened boat conformation, and the plane through the four coplanar atoms(C2, N3, C5 and C6) makes a dihedral angle of 89.65 (7)° with the benzene ring. The carbonyl, acetyl and methyl groups, except for the H atoms, are nearly coplanar with the attached heterocyclic ring. A network of hydrogen bonds (Table 1) help to establish the packing (Fig. 2, Table 1).

Related literature top

For chemical and medicinal background, see: Atwal et al. (1989); Ghorab et al. (2000); Kappe (1993, 2000); Kappe et al. (1997, 2000); Shivarama Holla et al. (2004); Stefani et al. (2006).

Experimental top

A solution of acetylacetone (1.00 g, 0.01 mol), anisaldehyde (1.36 g, 0.01 mol) and urea (0.90 g, 0.015 mol) in EtOH (20 ml) was heated under reflux in the presence of calcium chloride (0.11 g, 0.001 mol) for 3 h (monitored by TLC). After completion of the reaction, the reaction mixture was cooled to room temperature and the reaction mixture was poured into crushed ice and the resulting solid was filtered under suction and purified by column chromatography on silica gel. Elution of 1:1 (benzene:ethyl acetate v/v) gave the product in the pure form. Yield 0.86 g (96%).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT-NT (Bruker, 2004); data reduction: SAINT-NT (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: PLATON (Spek, 2003).

Figures top

	Fig. 1. The molecular structure of (I) with displacement ellipsoids drawn at the 30% probability level. H atoms are shown as small spheres of arbitrary radius.
	Fig. 2. The packing of (I), viewed down the b axis. Dashed lines indicate hydrogen bonds. H atoms not involved in hydrogen bonding have been omitted.

5-Acetyl-4-(4-methoxyphenyl)-6-methyl-3,4-dihydropyrimidin-2(1H)-one top

Crystal data top

C₁₄H₁₆N₂O₃	F(000) = 1104
M_r = 260.29	D_x = 1.323 Mg m⁻³
Monoclinic, C2/c	Melting point: 474.5 K
Hall symbol: -C 2yc	Mo Kα radiation, λ = 0.71073 Å
a = 23.7948 (12) Å	Cell parameters from 5096 reflections
b = 7.9905 (3) Å	θ = 2.7–26.4°
c = 14.4757 (7) Å	µ = 0.09 mm⁻¹
β = 108.305 (5)°	T = 293 K
V = 2613.0 (2) Å³	Block, colourless
Z = 8	0.3 × 0.2 × 0.2 mm

Data collection top

Bruker Kappa APEXII CCD diffractometer	2960 independent reflections
Radiation source: fine-focus sealed tube	2226 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.045
ω and ϕ scans	θ_max = 27.5°, θ_min = 1.8°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −30→30
T_min = 0.837, T_max = 1.000	k = −10→10
26518 measured reflections	l = −18→18

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.149	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	w = 1/[σ²(F_o²) + (0.0771P)² + 1.0144P] where P = (F_o² + 2F_c²)/3
2960 reflections	(Δ/σ)_max = 0.001
183 parameters	Δρ_max = 0.27 e Å⁻³
0 restraints	Δρ_min = −0.24 e Å⁻³

Crystal data top

C₁₄H₁₆N₂O₃	V = 2613.0 (2) Å³
M_r = 260.29	Z = 8
Monoclinic, C2/c	Mo Kα radiation
a = 23.7948 (12) Å	µ = 0.09 mm⁻¹
b = 7.9905 (3) Å	T = 293 K
c = 14.4757 (7) Å	0.3 × 0.2 × 0.2 mm
β = 108.305 (5)°

Data collection top

Bruker Kappa APEXII CCD diffractometer	2960 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2004)	2226 reflections with I > 2σ(I)
T_min = 0.837, T_max = 1.000	R_int = 0.045
26518 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	0 restraints
wR(F²) = 0.149	H atoms treated by a mixture of independent and constrained refinement
S = 1.10	Δρ_max = 0.27 e Å⁻³
2960 reflections	Δρ_min = −0.24 e Å⁻³
183 parameters

Special details top

Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles

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
O2	0.03463 (6)	0.62339 (16)	−0.06612 (9)	0.0448 (4)
O15	0.06948 (6)	0.98745 (15)	0.31847 (8)	0.0430 (4)
O44	0.27417 (7)	0.4726 (2)	0.44596 (12)	0.0748 (6)
N1	0.07453 (7)	0.86574 (18)	0.00570 (10)	0.0358 (4)
N3	0.04449 (7)	0.66399 (18)	0.09271 (10)	0.0351 (4)
C2	0.05037 (7)	0.7104 (2)	0.00812 (11)	0.0319 (5)
C4	0.06651 (7)	0.75657 (19)	0.18405 (11)	0.0297 (4)
C5	0.07616 (7)	0.93953 (19)	0.16471 (11)	0.0294 (5)
C6	0.08211 (7)	0.98438 (19)	0.07810 (11)	0.0303 (5)
C14	0.27926 (12)	0.4564 (4)	0.54607 (19)	0.0879 (11)
C15	0.07743 (7)	1.0494 (2)	0.24592 (11)	0.0332 (5)
C16	0.08710 (11)	1.2339 (2)	0.24595 (14)	0.0558 (7)
C41	0.12158 (7)	0.67712 (19)	0.25352 (11)	0.0320 (5)
C42	0.17355 (9)	0.6594 (3)	0.23045 (14)	0.0514 (7)
C43	0.22307 (10)	0.5896 (3)	0.29545 (17)	0.0624 (8)
C44	0.22238 (9)	0.5391 (3)	0.38624 (14)	0.0493 (6)
C45	0.17137 (9)	0.5551 (2)	0.41034 (13)	0.0436 (6)
C46	0.12122 (8)	0.6231 (2)	0.34341 (12)	0.0362 (5)
C61	0.09756 (9)	1.1526 (2)	0.04681 (13)	0.0424 (6)
H1	0.0736 (9)	0.901 (3)	−0.0548 (16)	0.048 (6)*
H3	0.0231 (9)	0.572 (3)	0.0913 (14)	0.046 (6)*
H4	0.03559	0.75256	0.21553	0.0356*
H14A	0.27276	0.56325	0.57124	0.1316*
H14B	0.31818	0.41685	0.58148	0.1316*
H14C	0.25029	0.37800	0.55309	0.1316*
H16A	0.08324	1.28140	0.30456	0.0837*
H16B	0.05821	1.28296	0.19064	0.0837*
H16C	0.12608	1.25601	0.24265	0.0837*
H42	0.17493	0.69534	0.17010	0.0616*
H43	0.25728	0.57630	0.27812	0.0749*
H45	0.17030	0.52054	0.47112	0.0523*
H46	0.08658	0.63227	0.35988	0.0434*
H61A	0.06570	1.22943	0.04172	0.0636*
H61B	0.10388	1.14266	−0.01528	0.0636*
H61C	0.13299	1.19346	0.09397	0.0636*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
O2	0.0622 (9)	0.0433 (7)	0.0320 (7)	−0.0143 (6)	0.0191 (6)	−0.0122 (5)
O15	0.0643 (9)	0.0401 (7)	0.0261 (6)	0.0044 (6)	0.0164 (6)	−0.0015 (5)
O44	0.0478 (9)	0.0956 (13)	0.0681 (11)	0.0106 (9)	−0.0003 (8)	0.0305 (10)
N1	0.0501 (9)	0.0354 (7)	0.0249 (7)	−0.0069 (6)	0.0160 (6)	−0.0019 (6)
N3	0.0469 (9)	0.0314 (7)	0.0264 (7)	−0.0105 (6)	0.0108 (6)	−0.0029 (5)
C2	0.0358 (9)	0.0334 (8)	0.0263 (8)	−0.0038 (7)	0.0094 (7)	−0.0037 (6)
C4	0.0380 (9)	0.0294 (7)	0.0233 (7)	−0.0033 (6)	0.0119 (7)	−0.0004 (6)
C5	0.0339 (9)	0.0279 (7)	0.0251 (8)	0.0007 (6)	0.0074 (6)	0.0002 (6)
C6	0.0331 (9)	0.0297 (8)	0.0266 (8)	0.0002 (6)	0.0074 (6)	−0.0003 (6)
C14	0.0716 (18)	0.102 (2)	0.0639 (17)	−0.0019 (16)	−0.0163 (13)	0.0314 (15)
C15	0.0388 (9)	0.0335 (8)	0.0240 (8)	0.0044 (7)	0.0051 (7)	−0.0013 (6)
C16	0.0959 (18)	0.0337 (9)	0.0369 (10)	−0.0012 (10)	0.0196 (11)	−0.0053 (8)
C41	0.0396 (9)	0.0275 (7)	0.0288 (8)	−0.0036 (7)	0.0108 (7)	−0.0002 (6)
C42	0.0474 (12)	0.0697 (13)	0.0400 (10)	0.0058 (10)	0.0181 (9)	0.0166 (9)
C43	0.0406 (12)	0.0861 (17)	0.0623 (14)	0.0084 (11)	0.0188 (10)	0.0201 (12)
C44	0.0436 (11)	0.0487 (11)	0.0469 (11)	0.0012 (9)	0.0017 (9)	0.0111 (9)
C45	0.0548 (12)	0.0399 (9)	0.0329 (9)	0.0014 (9)	0.0090 (8)	0.0082 (8)
C46	0.0454 (10)	0.0330 (8)	0.0314 (9)	0.0005 (7)	0.0139 (7)	0.0022 (7)
C61	0.0613 (12)	0.0324 (8)	0.0360 (9)	−0.0030 (8)	0.0188 (9)	0.0029 (7)

Geometric parameters (Å, º) top

O2—C2	1.235 (2)	C42—C43	1.374 (3)
O15—C15	1.228 (2)	C43—C44	1.380 (3)
O44—C14	1.422 (3)	C44—C45	1.370 (3)
O44—C44	1.371 (3)	C45—C46	1.390 (3)
N1—C2	1.373 (2)	C4—H4	0.9800
N1—C6	1.382 (2)	C14—H14A	0.9600
N3—C2	1.328 (2)	C14—H14B	0.9600
N3—C4	1.461 (2)	C14—H14C	0.9600
N1—H1	0.91 (2)	C16—H16A	0.9600
N3—H3	0.89 (2)	C16—H16B	0.9600
C4—C41	1.518 (2)	C16—H16C	0.9600
C4—C5	1.520 (2)	C42—H42	0.9300
C5—C6	1.354 (2)	C43—H43	0.9300
C5—C15	1.460 (2)	C45—H45	0.9300
C6—C61	1.501 (2)	C46—H46	0.9300
C15—C16	1.492 (2)	C61—H61A	0.9600
C41—C46	1.374 (2)	C61—H61B	0.9600
C41—C42	1.386 (3)	C61—H61C	0.9600

C14—O44—C44	116.75 (19)	C41—C46—C45	121.59 (18)
C2—N1—C6	123.82 (14)	N3—C4—H4	107.00
C2—N3—C4	125.54 (14)	C5—C4—H4	107.00
C2—N1—H1	114.8 (15)	C41—C4—H4	107.00
C6—N1—H1	118.3 (15)	O44—C14—H14A	109.00
C2—N3—H3	115.7 (13)	O44—C14—H14B	109.00
C4—N3—H3	118.6 (13)	O44—C14—H14C	109.00
O2—C2—N3	123.64 (16)	H14A—C14—H14B	109.00
N1—C2—N3	116.24 (14)	H14A—C14—H14C	109.00
O2—C2—N1	120.11 (15)	H14B—C14—H14C	109.00
N3—C4—C5	110.63 (13)	C15—C16—H16A	109.00
N3—C4—C41	112.17 (13)	C15—C16—H16B	109.00
C5—C4—C41	112.06 (13)	C15—C16—H16C	109.00
C4—C5—C15	113.35 (13)	H16A—C16—H16B	109.00
C6—C5—C15	127.23 (14)	H16A—C16—H16C	109.00
C4—C5—C6	119.42 (14)	H16B—C16—H16C	109.00
N1—C6—C5	119.61 (14)	C41—C42—H42	119.00
N1—C6—C61	111.81 (14)	C43—C42—H42	120.00
C5—C6—C61	128.58 (14)	C42—C43—H43	120.00
C5—C15—C16	123.96 (15)	C44—C43—H43	120.00
O15—C15—C5	118.45 (14)	C44—C45—H45	120.00
O15—C15—C16	117.59 (15)	C46—C45—H45	120.00
C4—C41—C46	119.88 (16)	C41—C46—H46	119.00
C42—C41—C46	117.89 (16)	C45—C46—H46	119.00
C4—C41—C42	122.22 (15)	C6—C61—H61A	109.00
C41—C42—C43	120.97 (19)	C6—C61—H61B	109.00
C42—C43—C44	120.4 (2)	C6—C61—H61C	109.00
O44—C44—C43	115.9 (2)	H61A—C61—H61B	109.00
C43—C44—C45	119.5 (2)	H61A—C61—H61C	109.00
O44—C44—C45	124.64 (18)	H61B—C61—H61C	109.00
C44—C45—C46	119.62 (17)

C14—O44—C44—C43	165.7 (2)	C4—C5—C6—N1	5.3 (3)
C14—O44—C44—C45	−15.5 (3)	C4—C5—C6—C61	−173.60 (17)
C6—N1—C2—O2	166.26 (17)	C15—C5—C6—N1	−174.25 (17)
C6—N1—C2—N3	−12.6 (3)	C15—C5—C6—C61	6.9 (3)
C2—N1—C6—C5	12.8 (3)	C4—C5—C15—O15	−1.7 (2)
C2—N1—C6—C61	−168.20 (17)	C4—C5—C15—C16	179.10 (18)
C4—N3—C2—O2	174.99 (17)	C6—C5—C15—O15	177.84 (18)
C4—N3—C2—N1	−6.2 (3)	C6—C5—C15—C16	−1.4 (3)
C2—N3—C4—C5	21.4 (2)	C4—C41—C42—C43	178.86 (19)
C2—N3—C4—C41	−104.54 (19)	C46—C41—C42—C43	0.2 (3)
N3—C4—C5—C6	−20.2 (2)	C4—C41—C46—C45	−177.71 (15)
N3—C4—C5—C15	159.41 (15)	C42—C41—C46—C45	1.0 (3)
C41—C4—C5—C6	105.84 (17)	C41—C42—C43—C44	−1.5 (4)
C41—C4—C5—C15	−74.59 (18)	C42—C43—C44—O44	−179.4 (2)
N3—C4—C41—C42	61.2 (2)	C42—C43—C44—C45	1.7 (3)
N3—C4—C41—C46	−120.13 (16)	O44—C44—C45—C46	−179.37 (19)
C5—C4—C41—C42	−64.0 (2)	C43—C44—C45—C46	−0.5 (3)
C5—C4—C41—C46	114.72 (17)	C44—C45—C46—C41	−0.9 (3)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O15ⁱ	0.91 (2)	2.01 (2)	2.9209 (18)	172 (2)
N3—H3···O2ⁱⁱ	0.89 (2)	2.04 (2)	2.917 (2)	170.3 (19)
C16—H16B···O2ⁱⁱⁱ	0.96	2.49	3.425 (3)	165
C61—H61B···O15ⁱ	0.96	2.51	3.352 (2)	146

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

Experimental details

Crystal data
Chemical formula	C₁₄H₁₆N₂O₃
M_r	260.29
Crystal system, space group	Monoclinic, C2/c
Temperature (K)	293
a, b, c (Å)	23.7948 (12), 7.9905 (3), 14.4757 (7)
β (°)	108.305 (5)
V (Å³)	2613.0 (2)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.09
Crystal size (mm)	0.3 × 0.2 × 0.2

Data collection
Diffractometer	Bruker Kappa APEXII CCD diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2004)
T_min, T_max	0.837, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	26518, 2960, 2226
R_int	0.045
(sin θ/λ)_max (Å⁻¹)	0.649

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.149, 1.10
No. of reflections	2960
No. of parameters	183
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.27, −0.24

Computer programs: APEX2 (Bruker, 2004), SAINT-NT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O15ⁱ	0.91 (2)	2.01 (2)	2.9209 (18)	172 (2)
N3—H3···O2ⁱⁱ	0.89 (2)	2.04 (2)	2.917 (2)	170.3 (19)
C16—H16B···O2ⁱⁱⁱ	0.96	2.49	3.425 (3)	165
C61—H61B···O15ⁱ	0.96	2.51	3.352 (2)	146

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

Acknowledgements

AT thanks the UGC, India, for the award of a Minor Research Project [File No. MRP-2355/06(UGC-SERO), Link No. 2355, 10/01/2007]. The authors are grateful to Dr A. Babu Vargheese, Sophisticated Analytical Instrument Facility (SAIF), IIT Madras, Chennai, for the X-ray data collection.

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