5-(4-Chloro­anilinomethyl­ene)-2,2-dimethyl-1,3-dioxane-4,6-dione

Yang, J.-C.; Shi, J.-Y.; Luo, Y.-F.; Qiu, N.; Chen, L.-J.

doi:10.1107/S1600536809023897

organic compounds

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ISSN: 2056-9890

Volume 65| Part 7| July 2009| Page o1706

doi:10.1107/S1600536809023897

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5-(4-Chloroanilinomethylene)-2,2-dimethyl-1,3-dioxane-4,6-dione

Jin-Cheng Yang,^a Jian-You Shi,^a You-Fu Luo,^b Neng Qiu ^b and Li-Juan Chen ^a,^b ^*

^aDepartment of Medicinal Chemistry, West China School of Pharmacy, Sichuan University, Chengdu 610041, People's Republic of China, and ^bState Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu 610041, People's Republic of China
^*Correspondence e-mail: jincool.1129@163.com.cn

(Received 26 May 2009; accepted 22 June 2009; online 27 June 2009)

The title compound, C₁₃H₁₂ClNO₄, is approximately planar, with a dihedral angle of 8.23 (4)° between the mean plane of the aminomethylene unit and the planar part of the dioxane ring. The dioxane ring has a half-boat conformation, in which the C atom between the dioxane O atoms is −0.464 (8) Å out of the plane of the other five atoms. In the molecule there is an intramolecular N—H⋯O hydrogen bond, involving the NH H atom and the adjacent dioxane carbonyl O atom. In the crystal, weak intermolecular C—H⋯O hydrogen-bonding contacts, result in the formation of sheets parallel to the ab plane.

Related literature

For the synthesis of related compounds, see: Cassis et al. (1985 ). For the synthesis of related antitumor precursors, see: Ruchelman et al. (2003 ). For details of the formation of quinolin-4-ol derivatives by thermal cracking, see: De et al. (1998 ). For the structure of 5-(aminomethylene)-2,2-dimethyl-1,3-dioxane-4,6-dione, see: da Silva et al. (2006 ).

Experimental

Crystal data

C₁₃H₁₂ClNO₄
M_r = 281.69
Monoclinic, P 2₁ /c
a = 13.439 (4) Å
b = 13.076 (3) Å
c = 7.723 (3) Å
β = 106.40 (2)°
V = 1302.0 (7) Å³
Z = 4
Mo Kα radiation
μ = 0.30 mm⁻¹
T = 293 K
0.46 × 0.44 × 0.22 mm

Data collection

Enraf–Nonius CAD-4 diffractometer
Absorption correction: spherical (WinGX; Farrugia, 1999 )T_min = 0.873, T_max = 0.936
2572 measured reflections
2404 independent reflections
1420 reflections with I > 2σ(I)
R_int = 0.007
3 standard reflections every 180 reflections intensity decay: 1.2%

Refinement

R[F² > 2σ(F²)] = 0.047
wR(F²) = 0.150
S = 1.08
2404 reflections
178 parameters
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.21 e Å⁻³
Δρ_min = −0.28 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1N⋯O4	0.90 (4)	2.10 (4)	2.753 (3)	129 (3)
C13—H13⋯O3ⁱ	0.93	2.53	3.384 (4)	153
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: DIFRAC (Gabe & White, 1993 ); cell refinement: DIFRAC; data reduction: NRCVAX (Gabe et al., 1989 ); 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, 2009 ).

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809023897/su2117sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809023897/su2117Isup2.hkl

checkCIF report

Comment top

Quinolin-4-ol is an important model compound in the field of medicinal chemistry, and the synthesis of related compounds has been described previously (Cassis et al., 1985). These compounds have been used as precursors for antitumor agents (Ruchelman et al., 2003). 2,2-dimethyl-5- ((phenylamino)methylene)-1,3-dioxane-4,6-diones are the key intermediates to synthesize the quinolin-4-ol derivatives by thermal cracking (De et al., 1998). The crystal structure of one such precursor, 5-(Aminomethylene)-2,2-dimethyl-1,3-dioxane-4,6-dione, has been descibed previously (de Silva et al., 2006).

The title compound (Fig. 1) is approximately planar with a dihedral angle of 8.23 (4)° between the connecting aminomethylene unit and the planar part of the dioxane ring. Apart from that, the dioxane ring of the title compound exhibits a half-boat conformation, in which the C atom (C39) between the dioxane O-atoms is -0.464 (8) Å out-of-plane of the other five atoms. The molecule has an intramolecular N—H···O hydrogen bond which can stabilize the planar conformation (Table 1).

In the crystal the molecules stack in layers along the [001] direction (Fig. 2).

Related literature top

For the synthesis of related compounds, see: Cassis et al. (1985). For the synthesis of related antitumor precursors, see: Ruchelman et al. (2003). For details of the formation of quinolin-4-ol derivatives by thermal cracking, see: De et al. (1998). For the structure of 5-(aminomethylene)-2,2-dimethyl-1,3-dioxane-4,6-dione, see: da Silva et al. (2006).

Experimental top

4-chlorobenzenamine(10 g,79.4 mmol), 2,2-dimethyl-1,3-dioxane-4,6-dione(13.6 g,94.1 mmol) and triethoxymethane(14 g,94.1 mmol) were suspended in ethanol at 363 K for 30 min. The white precipitate that formed was filtered off and recrystallized from acetone, giving colourless block-like crystals, suitable for X-ray diffraction analysis.

Computing details top

Data collection: DIFRAC (Gabe & White, 1993); cell refinement: DIFRAC (Gabe & White, 1993; data reduction: NRCVAX (Gabe et al., 1989); 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 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound, with displacement ellipsoids drawn at the 30% probability level.
	Fig. 2. A crystal packing diagram of the title compound, showing the layer-like aggregation of the molecules in the unit cell.

5-(4-Chloroanilinomethylene)-2,2-dimethyl-1,3-dioxane-4,6-dione top

Crystal data top

C₁₃H₁₂ClNO₄	F(000) = 584
M_r = 281.69	D_x = 1.437 Mg m⁻³
Monoclinic, P2₁/c	Mo Kα radiation, λ = 0.71073 Å
a = 13.439 (4) Å	Cell parameters from 24 reflections
b = 13.076 (3) Å	θ = 4.7–7.1°
c = 7.723 (3) Å	µ = 0.30 mm⁻¹
β = 106.40 (2)°	T = 293 K
V = 1302.0 (7) Å³	Block, colourless
Z = 4	0.46 × 0.44 × 0.22 mm

Data collection top

Enraf–Nonius CAD-4 diffractometer	1420 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.007
Graphite monochromator	θ_max = 25.5°, θ_min = 1.6°
ω/2θ scans	h = −9→16
Absorption correction: for a sphere (PROGRAM? REFERENCE?)	k = −15→0
T_min = 0.873, T_max = 0.936	l = −9→8
2572 measured reflections	3 standard reflections every 180 reflections
2404 independent reflections	intensity decay: 1.2%

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)] = 0.047	Hydrogen site location: mixed
wR(F²) = 0.150	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	w = 1/[σ²(F_o²) + (0.0786P)² + 0.0858P] where P = (F_o² + 2F_c²)/3
2404 reflections	(Δ/σ)_max < 0.001
178 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.28 e Å⁻³

Crystal data top

C₁₃H₁₂ClNO₄	V = 1302.0 (7) Å³
M_r = 281.69	Z = 4
Monoclinic, P2₁/c	Mo Kα radiation
a = 13.439 (4) Å	µ = 0.30 mm⁻¹
b = 13.076 (3) Å	T = 293 K
c = 7.723 (3) Å	0.46 × 0.44 × 0.22 mm
β = 106.40 (2)°

Data collection top

Enraf–Nonius CAD-4 diffractometer	1420 reflections with I > 2σ(I)
Absorption correction: for a sphere (PROGRAM? REFERENCE?)	R_int = 0.007
T_min = 0.873, T_max = 0.936	3 standard reflections every 180 reflections
2572 measured reflections	intensity decay: 1.2%
2404 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.047	0 restraints
wR(F²) = 0.150	H atoms treated by a mixture of independent and constrained refinement
S = 1.08	Δρ_max = 0.21 e Å⁻³
2404 reflections	Δρ_min = −0.28 e Å⁻³
178 parameters

Special details top

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 (Å²) top

	x	y	z	U_iso*/U_eq
Cl1	0.05313 (6)	0.85662 (7)	0.57925 (14)	0.0831 (4)
O1	0.71758 (14)	0.55344 (14)	0.3484 (3)	0.0558 (5)
O2	0.76628 (14)	0.72663 (14)	0.4111 (3)	0.0583 (5)
O3	0.55736 (15)	0.50190 (16)	0.3128 (3)	0.0713 (7)
O4	0.65479 (16)	0.84296 (15)	0.4491 (3)	0.0697 (7)
N1	0.46550 (18)	0.77642 (19)	0.4765 (3)	0.0515 (6)
H1N	0.505 (3)	0.833 (3)	0.478 (5)	0.082 (11)*
C1	0.8833 (2)	0.6088 (3)	0.3472 (5)	0.0759 (10)
H1A	0.9068	0.5391	0.3581	0.114*
H1B	0.9402	0.6532	0.4030	0.114*
H1C	0.8566	0.6262	0.2219	0.114*
C2	0.8321 (3)	0.5976 (3)	0.6385 (5)	0.0845 (11)
H2A	0.7740	0.6062	0.6865	0.127*
H2B	0.8868	0.6433	0.6990	0.127*
H2C	0.8563	0.5283	0.6568	0.127*
C3	0.7991 (2)	0.6212 (2)	0.4392 (4)	0.0554 (8)
C4	0.6196 (2)	0.5702 (2)	0.3595 (4)	0.0520 (7)
C5	0.5988 (2)	0.6710 (2)	0.4166 (4)	0.0474 (7)
C6	0.6714 (2)	0.7528 (2)	0.4304 (4)	0.0510 (7)
C7	0.5018 (2)	0.6873 (2)	0.4428 (4)	0.0502 (7)
H7	0.4591	0.6306	0.4359	0.060*
C8	0.3672 (2)	0.7933 (2)	0.5068 (4)	0.0458 (6)
C9	0.3339 (2)	0.8928 (2)	0.5081 (4)	0.0552 (7)
H9	0.3763	0.9466	0.4943	0.066*
C10	0.2368 (2)	0.9123 (2)	0.5301 (4)	0.0598 (8)
H10	0.2133	0.9792	0.5300	0.072*
C11	0.1759 (2)	0.8326 (2)	0.5519 (4)	0.0539 (7)
C12	0.2097 (2)	0.7335 (2)	0.5563 (4)	0.0579 (8)
H12	0.1679	0.6801	0.5741	0.069*
C13	0.3064 (2)	0.7134 (2)	0.5341 (4)	0.0552 (8)
H13	0.3303	0.6465	0.5376	0.066*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl1	0.0530 (5)	0.0953 (7)	0.1049 (8)	0.0101 (4)	0.0289 (5)	−0.0146 (5)
O1	0.0536 (11)	0.0520 (11)	0.0675 (13)	0.0026 (9)	0.0264 (10)	−0.0050 (10)
O2	0.0521 (11)	0.0511 (12)	0.0757 (14)	0.0003 (9)	0.0247 (10)	0.0013 (10)
O3	0.0645 (13)	0.0511 (12)	0.1081 (19)	−0.0080 (11)	0.0402 (13)	−0.0106 (12)
O4	0.0659 (13)	0.0443 (12)	0.1022 (19)	0.0001 (10)	0.0290 (13)	−0.0039 (11)
N1	0.0516 (13)	0.0486 (14)	0.0561 (16)	0.0029 (12)	0.0180 (12)	−0.0002 (11)
C1	0.0557 (18)	0.077 (2)	0.101 (3)	0.0016 (16)	0.0322 (18)	−0.008 (2)
C2	0.089 (2)	0.093 (3)	0.064 (2)	0.025 (2)	0.0100 (19)	0.0038 (19)
C3	0.0518 (16)	0.0520 (17)	0.063 (2)	0.0043 (14)	0.0175 (14)	−0.0017 (15)
C4	0.0551 (16)	0.0477 (16)	0.0598 (19)	0.0009 (14)	0.0270 (14)	0.0041 (14)
C5	0.0488 (14)	0.0464 (15)	0.0498 (17)	0.0015 (12)	0.0185 (13)	0.0004 (13)
C6	0.0554 (17)	0.0478 (17)	0.0504 (18)	0.0038 (13)	0.0159 (13)	0.0030 (13)
C7	0.0597 (17)	0.0468 (16)	0.0466 (17)	0.0020 (13)	0.0191 (14)	0.0037 (13)
C8	0.0471 (14)	0.0503 (16)	0.0413 (16)	0.0015 (12)	0.0147 (12)	0.0004 (13)
C9	0.0622 (17)	0.0482 (17)	0.0599 (19)	0.0001 (14)	0.0248 (15)	0.0039 (14)
C10	0.0685 (19)	0.0480 (17)	0.065 (2)	0.0133 (15)	0.0227 (16)	0.0032 (14)
C11	0.0458 (15)	0.0615 (18)	0.0534 (19)	0.0071 (14)	0.0122 (13)	−0.0020 (14)
C12	0.0530 (16)	0.0529 (18)	0.070 (2)	−0.0026 (14)	0.0221 (15)	−0.0012 (15)
C13	0.0579 (17)	0.0430 (15)	0.067 (2)	0.0071 (13)	0.0223 (15)	0.0016 (14)

Geometric parameters (Å, º) top

Cl1—C11	1.751 (3)	C2—H2B	0.9600
O1—C4	1.361 (3)	C2—H2C	0.9600
O1—C3	1.429 (3)	C4—C5	1.442 (4)
O2—C6	1.369 (3)	C5—C7	1.390 (4)
O2—C3	1.445 (3)	C5—C6	1.431 (4)
O3—C4	1.207 (3)	C7—H7	0.9300
O4—C6	1.216 (3)	C8—C9	1.377 (4)
N1—C7	1.318 (3)	C8—C13	1.378 (4)
N1—C8	1.422 (3)	C9—C10	1.387 (4)
N1—H1N	0.90 (4)	C9—H9	0.9300
C1—C3	1.505 (4)	C10—C11	1.364 (4)
C1—H1A	0.9600	C10—H10	0.9300
C1—H1B	0.9600	C11—C12	1.371 (4)
C1—H1C	0.9600	C12—C13	1.383 (4)
C2—C3	1.509 (5)	C12—H12	0.9300
C2—H2A	0.9600	C13—H13	0.9300

C4—O1—C3	119.4 (2)	C7—C5—C4	117.0 (2)
C6—O2—C3	118.4 (2)	C6—C5—C4	121.3 (2)
C7—N1—C8	125.7 (3)	O4—C6—O2	117.6 (3)
C7—N1—H1N	118 (2)	O4—C6—C5	126.1 (3)
C8—N1—H1N	116 (2)	O2—C6—C5	116.2 (2)
C3—C1—H1A	109.5	N1—C7—C5	125.4 (3)
C3—C1—H1B	109.5	N1—C7—H7	117.3
H1A—C1—H1B	109.5	C5—C7—H7	117.3
C3—C1—H1C	109.5	C9—C8—C13	120.5 (2)
H1A—C1—H1C	109.5	C9—C8—N1	117.8 (2)
H1B—C1—H1C	109.5	C13—C8—N1	121.7 (3)
C3—C2—H2A	109.5	C8—C9—C10	119.6 (3)
C3—C2—H2B	109.5	C8—C9—H9	120.2
H2A—C2—H2B	109.5	C10—C9—H9	120.2
C3—C2—H2C	109.5	C11—C10—C9	119.5 (3)
H2A—C2—H2C	109.5	C11—C10—H10	120.2
H2B—C2—H2C	109.5	C9—C10—H10	120.2
O1—C3—O2	111.0 (2)	C10—C11—C12	121.3 (3)
O1—C3—C1	106.0 (2)	C10—C11—Cl1	119.8 (2)
O2—C3—C1	105.7 (2)	C12—C11—Cl1	118.9 (2)
O1—C3—C2	109.7 (3)	C11—C12—C13	119.4 (3)
O2—C3—C2	109.7 (2)	C11—C12—H12	120.3
C1—C3—C2	114.6 (3)	C13—C12—H12	120.3
O3—C4—O1	117.6 (2)	C8—C13—C12	119.6 (3)
O3—C4—C5	126.2 (2)	C8—C13—H13	120.2
O1—C4—C5	116.1 (2)	C12—C13—H13	120.2
C7—C5—C6	121.4 (2)

C4—O1—C3—O2	−44.6 (3)	C4—C5—C6—O2	−8.8 (4)
C4—O1—C3—C1	−158.9 (2)	C8—N1—C7—C5	−178.7 (3)
C4—O1—C3—C2	76.9 (3)	C6—C5—C7—N1	2.0 (5)
C6—O2—C3—O1	45.9 (3)	C4—C5—C7—N1	−172.6 (3)
C6—O2—C3—C1	160.4 (2)	C7—N1—C8—C9	−168.6 (3)
C6—O2—C3—C2	−75.6 (3)	C7—N1—C8—C13	11.4 (4)
C3—O1—C4—O3	−165.7 (3)	C13—C8—C9—C10	−2.5 (4)
C3—O1—C4—C5	17.8 (4)	N1—C8—C9—C10	177.5 (3)
O3—C4—C5—C7	8.9 (4)	C8—C9—C10—C11	0.6 (4)
O1—C4—C5—C7	−175.0 (2)	C9—C10—C11—C12	1.4 (5)
O3—C4—C5—C6	−165.8 (3)	C9—C10—C11—Cl1	−179.9 (2)
O1—C4—C5—C6	10.3 (4)	C10—C11—C12—C13	−1.5 (5)
C3—O2—C6—O4	162.9 (3)	Cl1—C11—C12—C13	179.7 (2)
C3—O2—C6—C5	−20.3 (4)	C9—C8—C13—C12	2.4 (4)
C7—C5—C6—O4	−6.8 (5)	N1—C8—C13—C12	−177.6 (3)
C4—C5—C6—O4	167.6 (3)	C11—C12—C13—C8	−0.4 (5)
C7—C5—C6—O2	176.8 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O4	0.90 (4)	2.10 (4)	2.753 (3)	129 (3)
C13—H13···O3ⁱ	0.93	2.53	3.384 (4)	153

Symmetry code: (i) −x+1, −y+1, −z+1.

Experimental details

Crystal data
Chemical formula	C₁₃H₁₂ClNO₄
M_r	281.69
Crystal system, space group	Monoclinic, P2₁/c
Temperature (K)	293
a, b, c (Å)	13.439 (4), 13.076 (3), 7.723 (3)
β (°)	106.40 (2)
V (Å³)	1302.0 (7)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.30
Crystal size (mm)	0.46 × 0.44 × 0.22

Data collection
Diffractometer	Enraf–Nonius CAD-4 diffractometer
Absorption correction	For a sphere (PROGRAM? REFERENCE?)
T_min, T_max	0.873, 0.936
No. of measured, independent and observed [I > 2σ(I)] reflections	2572, 2404, 1420
R_int	0.007
(sin θ/λ)_max (Å⁻¹)	0.606

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.150, 1.08
No. of reflections	2404
No. of parameters	178
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.28

Computer programs: DIFRAC (Gabe & White, 1993), DIFRAC (Gabe & White, 1993, NRCVAX (Gabe et al., 1989), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O4	0.90 (4)	2.10 (4)	2.753 (3)	129 (3)
C13—H13···O3ⁱ	0.93	2.53	3.384 (4)	153

Symmetry code: (i) −x+1, −y+1, −z+1.

Acknowledgements

The authors thank Mr Zhi-Hua Mao of Sichuan University for the X-ray data collection.

References

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