organic compounds
2-{4-[(2,2-Dimethyl-4,6-dioxo-1,3-dioxan-5-ylidene)methylamino]phenyl}acetonitrile
aState Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, 610041, People's Republic of China, and bState Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai, 201203, People's Republic of China
*Correspondence e-mail: lirui@scu.edu.cn
The title compound, C15H14N2O4, is approximately planar, with a dihedral angle of 6.48 (4)° between the aminomethylene unit and the planar five-atom part of the dioxane ring, and a dihedral angle of 2.40 (4)° between aminomethylene unit and the phenylene ring. The dioxane ring is envelope shaped, with the dimethyl-substituted C atom that represents the flap 0.535 (8) Å out of the plane. The molecule has an intramolecular N—H⋯O hydrogen bond.
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 the of a related compound, see: da Silva et al. (2006). For Meldrum's acid, see: Meldrum (1908).
Experimental
Crystal data
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Data collection
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Refinement
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Data collection: DIFRAC (Gabe & White, 1993); cell 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
10.1107/S1600536809017437/ng2579sup1.cif
contains datablocks I, New_Global_Publ_Block. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809017437/ng2579Isup2.hkl
A ethanol solution (50 ml) of 2,2-dimethyl-1,3-dioxane-4,6-dione (Meldrum's acid) (1.44 g, 0.01 mol) and methylorthoformate (1.27 g, 0.012 mol) was heated to reflux for 2 h, then the arylamine (1.32 g, 0.01 mol) was added into the above solution. The mixture was heated under reflux for another 8 h and then filtered. Single crystals were obtained from the filtrate after 2 days.
The imino H atom was located in a difference Fourier map and refined isotropically. Other H atoms were positioned geometrically with C—H = 0.93 (aromatic) or 0.96 Å (methyl), and refined using a riding model with Uĩso(H) = 1.5Ueq(C) for methyl and 1.2Ueq(C) for the others.
Data collection: DIFRAC (Gabe & White, 1993); cell
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).C15H14N2O4 | Z = 2 |
Mr = 286.28 | F(000) = 300 |
Triclinic, P1 | Dx = 1.353 Mg m−3 |
a = 5.204 (3) Å | Mo Kα radiation, λ = 0.71073 Å |
b = 11.239 (3) Å | Cell parameters from 26 reflections |
c = 12.209 (4) Å | θ = 5.5–9.7° |
α = 85.51 (3)° | µ = 0.10 mm−1 |
β = 82.30 (3)° | T = 292 K |
γ = 84.54 (2)° | Block, colourless |
V = 702.9 (5) Å3 | 0.52 × 0.48 × 0.23 mm |
Enraf–Nonius CAD-4 diffractometer | Rint = 0.003 |
Radiation source: fine-focus sealed tube | θmax = 25.5°, θmin = 1.7° |
Graphite monochromator | h = −6→6 |
ω/2–θ scans | k = −2→13 |
3217 measured reflections | l = −14→14 |
2609 independent reflections | 3 standard reflections every 150 reflections |
1610 reflections with I > 2σ(I) | intensity decay: 1.3% |
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: mixed |
wR(F2) = 0.150 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | w = 1/[σ2(Fo2) + (0.0853P)2] where P = (Fo2 + 2Fc2)/3 |
2609 reflections | (Δ/σ)max < 0.001 |
196 parameters | Δρmax = 0.19 e Å−3 |
0 restraints | Δρmin = −0.20 e Å−3 |
C15H14N2O4 | γ = 84.54 (2)° |
Mr = 286.28 | V = 702.9 (5) Å3 |
Triclinic, P1 | Z = 2 |
a = 5.204 (3) Å | Mo Kα radiation |
b = 11.239 (3) Å | µ = 0.10 mm−1 |
c = 12.209 (4) Å | T = 292 K |
α = 85.51 (3)° | 0.52 × 0.48 × 0.23 mm |
β = 82.30 (3)° |
Enraf–Nonius CAD-4 diffractometer | Rint = 0.003 |
3217 measured reflections | 3 standard reflections every 150 reflections |
2609 independent reflections | intensity decay: 1.3% |
1610 reflections with I > 2σ(I) |
R[F2 > 2σ(F2)] = 0.048 | 0 restraints |
wR(F2) = 0.150 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.09 | Δρmax = 0.19 e Å−3 |
2609 reflections | Δρmin = −0.20 e Å−3 |
196 parameters |
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 | 0.5677 (3) | 0.03464 (12) | 0.29695 (11) | 0.0620 (4) | |
O2 | 0.8342 (3) | 0.19500 (12) | 0.26775 (11) | 0.0573 (4) | |
O3 | 0.2465 (3) | 0.02806 (12) | 0.43304 (11) | 0.0639 (4) | |
O4 | 0.7647 (3) | 0.35124 (12) | 0.36881 (12) | 0.0634 (4) | |
N1 | 0.1001 (3) | 0.22676 (14) | 0.54592 (13) | 0.0498 (4) | |
H1N | 0.074 (5) | 0.145 (2) | 0.5335 (18) | 0.091 (8)* | |
N2 | −0.9365 (5) | 0.3352 (2) | 0.9847 (2) | 0.1123 (9) | |
C1 | 0.9231 (5) | 0.0301 (2) | 0.1573 (2) | 0.0831 (8) | |
H1A | 1.0196 | 0.0754 | 0.0984 | 0.125* | |
H1B | 0.8480 | −0.0329 | 0.1271 | 0.125* | |
H1C | 1.0377 | −0.0040 | 0.2090 | 0.125* | |
C2 | 0.5317 (5) | 0.1765 (2) | 0.13934 (18) | 0.0744 (7) | |
H2A | 0.3912 | 0.2203 | 0.1823 | 0.112* | |
H2B | 0.4629 | 0.1198 | 0.0986 | 0.112* | |
H2C | 0.6268 | 0.2311 | 0.0886 | 0.112* | |
C3 | 0.7107 (4) | 0.11099 (19) | 0.21537 (16) | 0.0573 (6) | |
C4 | 0.4120 (4) | 0.08606 (17) | 0.38115 (16) | 0.0519 (5) | |
C5 | 0.4624 (4) | 0.20480 (16) | 0.40360 (15) | 0.0471 (5) | |
C6 | 0.6901 (4) | 0.25836 (17) | 0.34787 (15) | 0.0477 (5) | |
C7 | 0.3046 (4) | 0.26618 (16) | 0.48329 (15) | 0.0493 (5) | |
H7 | 0.3459 | 0.3428 | 0.4941 | 0.059* | |
C8 | −0.0785 (4) | 0.29056 (16) | 0.62235 (15) | 0.0472 (5) | |
C9 | −0.2817 (4) | 0.23184 (17) | 0.67757 (17) | 0.0568 (6) | |
H9 | −0.2971 | 0.1528 | 0.6638 | 0.068* | |
C10 | −0.4632 (4) | 0.28879 (18) | 0.75328 (16) | 0.0573 (6) | |
H10 | −0.5997 | 0.2476 | 0.7901 | 0.069* | |
C11 | −0.4454 (4) | 0.40591 (18) | 0.77514 (16) | 0.0507 (5) | |
C12 | −0.2402 (4) | 0.46434 (17) | 0.71855 (16) | 0.0535 (5) | |
H12 | −0.2253 | 0.5435 | 0.7321 | 0.064* | |
C13 | −0.0575 (4) | 0.40860 (17) | 0.64268 (16) | 0.0541 (5) | |
H13 | 0.0786 | 0.4497 | 0.6055 | 0.065* | |
C14 | −0.6446 (4) | 0.47201 (19) | 0.85500 (16) | 0.0608 (6) | |
H14A | −0.5548 | 0.5184 | 0.8994 | 0.073* | |
H14B | −0.7541 | 0.5278 | 0.8130 | 0.073* | |
C15 | −0.8082 (5) | 0.3952 (2) | 0.92822 (19) | 0.0722 (7) |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0652 (9) | 0.0508 (8) | 0.0660 (9) | −0.0175 (7) | 0.0196 (7) | −0.0113 (7) |
O2 | 0.0452 (8) | 0.0627 (8) | 0.0639 (9) | −0.0173 (7) | 0.0036 (7) | −0.0054 (7) |
O3 | 0.0655 (9) | 0.0509 (8) | 0.0712 (9) | −0.0237 (7) | 0.0208 (7) | −0.0066 (7) |
O4 | 0.0655 (10) | 0.0527 (8) | 0.0744 (9) | −0.0237 (7) | −0.0061 (8) | −0.0008 (7) |
N1 | 0.0521 (10) | 0.0400 (9) | 0.0560 (9) | −0.0069 (8) | 0.0003 (8) | −0.0045 (7) |
N2 | 0.112 (2) | 0.0951 (17) | 0.1082 (18) | −0.0057 (15) | 0.0499 (16) | 0.0130 (14) |
C1 | 0.0696 (17) | 0.0865 (18) | 0.0876 (17) | −0.0170 (15) | 0.0277 (14) | −0.0232 (15) |
C2 | 0.0662 (15) | 0.0952 (18) | 0.0641 (14) | −0.0285 (14) | −0.0041 (12) | −0.0003 (13) |
C3 | 0.0520 (12) | 0.0619 (12) | 0.0571 (12) | −0.0221 (11) | 0.0108 (10) | −0.0073 (10) |
C4 | 0.0511 (12) | 0.0481 (11) | 0.0539 (11) | −0.0108 (10) | 0.0060 (10) | −0.0019 (9) |
C5 | 0.0457 (11) | 0.0442 (10) | 0.0507 (11) | −0.0097 (9) | −0.0017 (9) | 0.0007 (9) |
C6 | 0.0449 (11) | 0.0456 (10) | 0.0523 (11) | −0.0087 (9) | −0.0041 (9) | 0.0016 (9) |
C7 | 0.0522 (12) | 0.0413 (10) | 0.0537 (11) | −0.0080 (9) | −0.0031 (10) | 0.0001 (9) |
C8 | 0.0477 (11) | 0.0442 (10) | 0.0489 (11) | −0.0069 (9) | −0.0019 (9) | −0.0016 (8) |
C9 | 0.0632 (14) | 0.0410 (11) | 0.0657 (13) | −0.0151 (10) | 0.0017 (11) | −0.0055 (10) |
C10 | 0.0567 (13) | 0.0499 (11) | 0.0631 (13) | −0.0166 (10) | 0.0086 (10) | −0.0036 (10) |
C11 | 0.0506 (12) | 0.0497 (11) | 0.0501 (11) | −0.0044 (9) | −0.0022 (9) | 0.0003 (9) |
C12 | 0.0563 (13) | 0.0397 (10) | 0.0630 (12) | −0.0061 (9) | 0.0018 (10) | −0.0068 (9) |
C13 | 0.0505 (12) | 0.0472 (11) | 0.0628 (12) | −0.0106 (10) | 0.0037 (10) | −0.0029 (9) |
C14 | 0.0619 (14) | 0.0592 (12) | 0.0572 (12) | −0.0039 (11) | 0.0071 (11) | −0.0049 (10) |
C15 | 0.0707 (16) | 0.0721 (15) | 0.0639 (14) | 0.0053 (13) | 0.0158 (12) | 0.0019 (12) |
O1—C4 | 1.352 (2) | C4—C5 | 1.438 (2) |
O1—C3 | 1.439 (2) | C5—C7 | 1.371 (3) |
O2—C6 | 1.356 (2) | C5—C6 | 1.444 (3) |
O2—C3 | 1.426 (2) | C7—H7 | 0.9300 |
O3—C4 | 1.210 (2) | C8—C9 | 1.371 (3) |
O4—C6 | 1.205 (2) | C8—C13 | 1.386 (3) |
N1—C7 | 1.316 (2) | C9—C10 | 1.379 (3) |
N1—C8 | 1.412 (2) | C9—H9 | 0.9300 |
N1—H1n | 0.96 (2) | C10—C11 | 1.378 (3) |
N2—C15 | 1.125 (3) | C10—H10 | 0.9300 |
C1—C3 | 1.500 (3) | C11—C12 | 1.383 (3) |
C1—H1A | 0.9600 | C11—C14 | 1.508 (3) |
C1—H1B | 0.9600 | C12—C13 | 1.377 (3) |
C1—H1C | 0.9600 | C12—H12 | 0.9300 |
C2—C3 | 1.505 (3) | C13—H13 | 0.9300 |
C2—H2A | 0.9600 | C14—C15 | 1.444 (3) |
C2—H2B | 0.9600 | C14—H14A | 0.9700 |
C2—H2C | 0.9600 | C14—H14B | 0.9700 |
C4—O1—C3 | 118.27 (15) | O4—C6—C5 | 125.76 (19) |
C6—O2—C3 | 118.41 (15) | O2—C6—C5 | 115.95 (15) |
C7—N1—C8 | 127.60 (16) | N1—C7—C5 | 126.03 (17) |
C7—N1—H1N | 112.8 (15) | N1—C7—H7 | 117.0 |
C8—N1—H1N | 119.5 (15) | C5—C7—H7 | 117.0 |
C3—C1—H1A | 109.5 | C9—C8—C13 | 119.39 (18) |
C3—C1—H1B | 109.5 | C9—C8—N1 | 117.65 (16) |
H1A—C1—H1B | 109.5 | C13—C8—N1 | 122.96 (17) |
C3—C1—H1C | 109.5 | C8—C9—C10 | 120.69 (17) |
H1A—C1—H1C | 109.5 | C8—C9—H9 | 119.7 |
H1B—C1—H1C | 109.5 | C10—C9—H9 | 119.7 |
C3—C2—H2A | 109.5 | C11—C10—C9 | 120.89 (19) |
C3—C2—H2B | 109.5 | C11—C10—H10 | 119.6 |
H2A—C2—H2B | 109.5 | C9—C10—H10 | 119.6 |
C3—C2—H2C | 109.5 | C10—C11—C12 | 117.88 (19) |
H2A—C2—H2C | 109.5 | C10—C11—C14 | 122.30 (19) |
H2B—C2—H2C | 109.5 | C12—C11—C14 | 119.80 (17) |
O2—C3—O1 | 110.49 (15) | C13—C12—C11 | 121.86 (17) |
O2—C3—C1 | 106.90 (17) | C13—C12—H12 | 119.1 |
O1—C3—C1 | 105.58 (18) | C11—C12—H12 | 119.1 |
O2—C3—C2 | 109.82 (18) | C12—C13—C8 | 119.30 (18) |
O1—C3—C2 | 110.28 (17) | C12—C13—H13 | 120.4 |
C1—C3—C2 | 113.65 (19) | C8—C13—H13 | 120.4 |
O3—C4—O1 | 117.85 (16) | C15—C14—C11 | 114.09 (18) |
O3—C4—C5 | 125.29 (18) | C15—C14—H14A | 108.7 |
O1—C4—C5 | 116.83 (16) | C11—C14—H14A | 108.7 |
C7—C5—C4 | 120.65 (17) | C15—C14—H14B | 108.7 |
C7—C5—C6 | 118.69 (16) | C11—C14—H14B | 108.7 |
C4—C5—C6 | 120.53 (17) | H14A—C14—H14B | 107.6 |
O4—C6—O2 | 118.25 (17) | N2—C15—C14 | 179.5 (3) |
C6—O2—C3—O1 | −49.2 (2) | C8—N1—C7—C5 | −174.51 (18) |
C6—O2—C3—C1 | −163.65 (17) | C4—C5—C7—N1 | 0.3 (3) |
C6—O2—C3—C2 | 72.6 (2) | C6—C5—C7—N1 | −175.62 (18) |
C4—O1—C3—O2 | 46.8 (2) | C7—N1—C8—C9 | 178.79 (18) |
C4—O1—C3—C1 | 162.08 (18) | C7—N1—C8—C13 | −0.7 (3) |
C4—O1—C3—C2 | −74.8 (2) | C13—C8—C9—C10 | −0.4 (3) |
C3—O1—C4—O3 | 162.19 (19) | N1—C8—C9—C10 | −179.96 (18) |
C3—O1—C4—C5 | −19.5 (3) | C8—C9—C10—C11 | 0.1 (3) |
O3—C4—C5—C7 | −5.6 (3) | C9—C10—C11—C12 | 0.2 (3) |
O1—C4—C5—C7 | 176.25 (17) | C9—C10—C11—C14 | 178.25 (19) |
O3—C4—C5—C6 | 170.2 (2) | C10—C11—C12—C13 | −0.1 (3) |
O1—C4—C5—C6 | −7.9 (3) | C14—C11—C12—C13 | −178.27 (19) |
C3—O2—C6—O4 | −158.33 (18) | C11—C12—C13—C8 | −0.2 (3) |
C3—O2—C6—C5 | 23.8 (2) | C9—C8—C13—C12 | 0.4 (3) |
C7—C5—C6—O4 | 4.2 (3) | N1—C8—C13—C12 | 179.96 (18) |
C4—C5—C6—O4 | −171.73 (19) | C10—C11—C14—C15 | 16.7 (3) |
C7—C5—C6—O2 | −178.17 (16) | C12—C11—C14—C15 | −165.3 (2) |
C4—C5—C6—O2 | 5.9 (3) | C11—C14—C15—N2 | −69 (31) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1n···O3 | 0.97 (2) | 1.94 (2) | 2.710 (3) | 135 (2) |
C7—H7···O4 | 0.93 | 2.49 | 2.816 (3) | 100 |
C9—H9···O3i | 0.93 | 2.41 | 3.292 (3) | 159 |
C13—H13···O4ii | 0.93 | 2.51 | 3.208 (3) | 132 |
C14—H14B···O4iii | 0.97 | 2.51 | 3.343 (3) | 143 |
Symmetry codes: (i) −x, −y, −z+1; (ii) −x+1, −y+1, −z+1; (iii) −x, −y+1, −z+1. |
Experimental details
Crystal data | |
Chemical formula | C15H14N2O4 |
Mr | 286.28 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 292 |
a, b, c (Å) | 5.204 (3), 11.239 (3), 12.209 (4) |
α, β, γ (°) | 85.51 (3), 82.30 (3), 84.54 (2) |
V (Å3) | 702.9 (5) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.10 |
Crystal size (mm) | 0.52 × 0.48 × 0.23 |
Data collection | |
Diffractometer | Enraf–Nonius CAD-4 diffractometer |
Absorption correction | – |
No. of measured, independent and observed [I > 2σ(I)] reflections | 3217, 2609, 1610 |
Rint | 0.003 |
(sin θ/λ)max (Å−1) | 0.606 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.048, 0.150, 1.09 |
No. of reflections | 2609 |
No. of parameters | 196 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.19, −0.20 |
Computer programs: DIFRAC (Gabe & White, 1993), NRCVAX (Gabe et al., 1989), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1n···O3 | 0.97 (2) | 1.94 (2) | 2.710 (3) | 135 (2) |
Acknowledgements
This research was supported financially by the State Key Laboratory of Drug Research (Shanghai Institute of Materia Medica, Chinese Academy of Sciences).
References
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This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited.
The 4(1H)quinolone structure plays an extremely important role in the field of pharmaceutical chemistry. These compounds have been used as precursors for anticancer agents, anti-malarial agents and reversible (H+/K+) ATPase inhibitors (Ruchelman et al.,2003). 5-arylaminomethylene-2,2-dimethyl-1,3-dioxane-4,6-diones are the key intermediates which can be used to synthesize the 4(1H)quinolone derivatives by thermolysis (Cassis et al., 1985).
In the structure of the title molecule (Fig. 1), it is approximately planar with the dihedral angles of 6.48 (4)° and 2.40 (4)° between the connecting aminomethylene unit and the planar part of the dioxane ring, and between the dimethoxybenzyl ring and the aminomethylene group, respectively. Besides, the dioxane ring of the title compound exhibits a half-boat conformation, in which the C atom between the dioxane oxygen atoms is -0.535 (8) Å out-of-plane.
The intramolecular N—H···O hydrogen bond (Table 1) is stabilizing the planar conformation in the molecule. Intermolecular weak C—H···O hydrogen bonding contacts (Table 1) result in the formation of sheets running parallel to the a-c plane in the crystal structure (Fig. 2).