organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

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ISSN: 2056-9890

2,6-Di­methyl-N-(2-methyl­phen­yl)-1,3-dioxan-4-amine

aCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India, bChemistry Department, GEBH, Sree Vidyanikethan Engineering College, A. Rangampet, Tirupati 517102, India, and cCentre for Organic and Medicinal Chemistry, VIT University, Vellore 632 014, India
*Correspondence e-mail: shirai2011@gmail.com

(Received 6 September 2013; accepted 11 September 2013; online 18 September 2013)

In the title compound, C13H19NO2, the dioxane ring adopts a chair conformation and its mean plane makes a dihedral angle of 45.36 (8)° with the phenyl ring. In the crystal, mol­ecules are linked by pairs of N—H⋯O hydrogen bonds, forming inversion dimers with R22(12) ring motifs. These dimers are consolidated by pairs of C—H⋯O hydrogen bonds with R22(8) ring motifs.

Related literature

For applications of 1,3-dioxane derivatives, see: Wang et al. (1996a[Wang, G. W., Yuan, X. Y., Lei, X. G. & Liu, Y. C. (1996a). Chin. J. Appl. Chem. 11, 114-115.],b[Wang, G. W., Yuan, X. Y., Liu, Y. C., Guo, Q. X. & Lei, X. G. (1996b). Indian J. Chem. Sect. B 35, 583-585.]); Yuan et al. (2005[Yuan, X. Y., Yang, N. F., Luo, H. A. & Liu, Y. J. (2005). Chin. J. Org. Chem. 25, 1049-1052.]). Dioxane rings are frequently encountered in many bioactive mol­ecules, some of which are cytotoxic agents (Aubele et al., 2005[Aubele, D. L., Wan, S. & Floreancig, P. E. (2005). Angew. Chem. Int. Ed. 44, 3485-3488.]) and anti­muscarinic agents (Marucci et al., 2005[Marucci, G., Piero, A., Brasili, L., Buccioni, M., Giardinà, D., Gulini, U., Piergentili, A. & Sagratini, G. (2005). Med. Chem. Res. 14, 274-296.]). For related crystal structures, see: Chuprunov et al. (1981[Chuprunov, E. V., Tarkhova, T. N., Korallova, T. Y., Simonov, M. A. & Belov, W. V. (1981). Zh. Strukt. Khim. 22, 191-192.]); Thevenet et al. (2010[Thevenet, D., Neier, R. & Stoeckli-Evans, H. (2010). Acta Cryst. E66, o473-o474.]); Fatima et al. (2013[Fatima, Z., Rambabu, G., Reddy, B. P., Vijayakumar, V. & Velmurugan, D. (2013). Acta Cryst. E69, o1524.]). For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C13H19NO2

  • Mr = 221.29

  • Monoclinic, P 21 /c

  • a = 8.0209 (2) Å

  • b = 7.8762 (2) Å

  • c = 20.4293 (5) Å

  • β = 99.066 (2)°

  • V = 1274.48 (6) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 293 K

  • 0.30 × 0.25 × 0.20 mm

Data collection
  • Bruker SMART APEXII area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, U. S. A.]) Tmin = 0.692, Tmax = 0.746

  • 12359 measured reflections

  • 3177 independent reflections

  • 2481 reflections with I > 2σ(I)

  • Rint = 0.019

Refinement
  • R[F2 > 2σ(F2)] = 0.040

  • wR(F2) = 0.119

  • S = 1.03

  • 3177 reflections

  • 152 parameters

  • H atoms treated by a mixture of independent and constrained refinement

  • Δρmax = 0.18 e Å−3

  • Δρmin = −0.12 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯O2i 0.843 (15) 2.559 (15) 3.3688 (13) 161.3 (13)
C3—H3A⋯O1i 0.97 2.54 3.4950 (13) 167
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, U. S. A.]); cell refinement: SAINT (Bruker, 2008[Bruker (2008). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, U. S. A.]); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012[Farrugia, L. J. (2012). J. Appl. Cryst. 45, 849-854.]) and Macrae et al., 2008[Macrae, C. F., Bruno, I. J., Chisholm, J. A., Edgington, P. R., McCabe, P., Pidcock, E., Rodriguez-Monge, L., Taylor, R., van de Streek, J. & Wood, P. A. (2008). J. Appl. Cryst. 41, 466-470.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

1,3-dioxane derivatives have applications in the pharmaceutical (Wang et al., 1996b) and cosmetics industry (Wang et al., 1996a; Yuan et al., 2005). Dioxane rings are frequently encountered in many bioactive molecules, some of which are cytotoxic agents (Aubele et al., 2005) and antimuscarinic agents (Marucci et al., 2005). In view of the excellent biological and pharmacological applications of this class of compounds, we have undertaken the synthesis of the title compound and report herein on its crystal structure.

In the title molecule, Fig. 1, the dioxane ring (O1/O2/C2—C5) adopts a chair conformation and its mean plane makes a dihedral angle of 45.36 (8)° with the phenyl ring (C7—C12).

In the crystal, molecules are linked by a pair of N-H···O hydrogen bonds forming inversion dimers with an R22(12) ring motif (Bernstein et al., 1995). These dimers are consolidated by a pair of C-H···O hydrogen bonds with an R22(8) ring motif (Table 1 and Fig. 2).

Related literature top

For applications of 1,3-dioxane derivatives, see: Wang et al. (1996a,b); Yuan et al. (2005). Dioxane rings are frequently encountered in many bioactive molecules, some of which are cytotoxic agents (Aubele et al., 2005) and antimuscarinic agents (Marucci et al., 2005). For related crystal structures, see: Chuprunov et al. (1981); Thevenet et al. (2010); Fatima et al. (2013). For hydrogen-bond motifs, see: Bernstein et al. (1995).

Experimental top

To 2-toulidine (1 mmol), acetaldehyde (3 mmol) was added drop wise and the mixture was stirred for ca. 4 h at 273 K. The progress of the reaction was monitored through TLC. On completion the reaction the mixture was washed with petroleum ether. The resultant mixture was dissolved in diethylether and the solvent allowed to evaporate. The solid product obtained was recrystallized with diethylether to yield block-like colourless crystals, suitable for X-ray diffraction analysis.

Refinement top

The NH H atom was located in a difference Fourier map and freely refined. The C bound H atoms were placed in calculated positions and refined as riding atoms: C—H = 0.93 - 0.98 Å with Uiso(H) = 1.5Ueq(C-methyl) and = 1.2Ueq(C) for other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012) and Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title molecule, with atom labelling. Displacement ellipsoids are drawn at the 30% probability level.
[Figure 2] Fig. 2. A view along the b axis of the crystal packing of the title compound. The N-H···O and C-H···O hydrogen bonds are shown as dashed lines (see Table 1 for details; H atoms not involved in hydrogen bonding have been omitted for clarity).
2,6-Dimethyl-N-(2-methylphenyl)-1,3-dioxan-4-amine top
Crystal data top
C13H19NO2F(000) = 480
Mr = 221.29Dx = 1.153 Mg m3
Monoclinic, P21/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybcCell parameters from 3177 reflections
a = 8.0209 (2) Åθ = 2.0–28.4°
b = 7.8762 (2) ŵ = 0.08 mm1
c = 20.4293 (5) ÅT = 293 K
β = 99.066 (2)°Block, colourless
V = 1274.48 (6) Å30.30 × 0.25 × 0.20 mm
Z = 4
Data collection top
Bruker SMART APEXII area-detector
diffractometer
3177 independent reflections
Radiation source: fine-focus sealed tube2481 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.019
ω and ϕ scansθmax = 28.4°, θmin = 2.0°
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
h = 1010
Tmin = 0.692, Tmax = 0.746k = 1010
12359 measured reflectionsl = 2627
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.040H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.119 w = 1/[σ2(Fo2) + (0.0553P)2 + 0.1687P]
where P = (Fo2 + 2Fc2)/3
S = 1.03(Δ/σ)max < 0.001
3177 reflectionsΔρmax = 0.18 e Å3
152 parametersΔρmin = 0.12 e Å3
0 restraintsExtinction correction: SHELXL, Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.077 (4)
Crystal data top
C13H19NO2V = 1274.48 (6) Å3
Mr = 221.29Z = 4
Monoclinic, P21/cMo Kα radiation
a = 8.0209 (2) ŵ = 0.08 mm1
b = 7.8762 (2) ÅT = 293 K
c = 20.4293 (5) Å0.30 × 0.25 × 0.20 mm
β = 99.066 (2)°
Data collection top
Bruker SMART APEXII area-detector
diffractometer
3177 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2008)
2481 reflections with I > 2σ(I)
Tmin = 0.692, Tmax = 0.746Rint = 0.019
12359 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0400 restraints
wR(F2) = 0.119H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.18 e Å3
3177 reflectionsΔρmin = 0.12 e Å3
152 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
xyzUiso*/Ueq
H10.3087 (18)0.4830 (19)0.5783 (7)0.067 (4)*
C10.31391 (18)0.68745 (18)0.35171 (7)0.0682 (4)
H1A0.32170.66100.30640.102*
H1B0.42120.72780.37370.102*
H1C0.23000.77380.35310.102*
C20.26506 (14)0.53043 (15)0.38614 (6)0.0509 (3)
H20.15700.48840.36270.061*
C30.24940 (13)0.56014 (14)0.45810 (5)0.0474 (3)
H3A0.35110.61470.48040.057*
H3B0.15500.63540.46070.057*
C40.22287 (12)0.39494 (14)0.49256 (5)0.0457 (3)
H40.11210.34890.47390.055*
C50.35637 (15)0.25112 (14)0.41290 (6)0.0511 (3)
H50.24770.20660.39100.061*
C60.4939 (2)0.12583 (18)0.40646 (8)0.0727 (4)
H6A0.49920.10720.36040.109*
H6B0.47030.02040.42670.109*
H6C0.60000.16970.42810.109*
C70.19069 (13)0.28783 (15)0.60341 (5)0.0475 (3)
C80.13383 (15)0.12993 (17)0.57909 (7)0.0570 (3)
H80.12400.10790.53390.068*
C90.09169 (17)0.00538 (19)0.62110 (8)0.0684 (4)
H90.05240.09910.60400.082*
C100.10746 (19)0.0348 (2)0.68794 (8)0.0773 (4)
H100.07990.04940.71630.093*
C110.16463 (19)0.1905 (2)0.71237 (7)0.0739 (4)
H110.17600.20960.75780.089*
C120.20590 (14)0.31981 (18)0.67183 (6)0.0573 (3)
C130.2628 (2)0.4902 (2)0.69976 (7)0.0778 (4)
H13A0.25370.49350.74600.117*
H13B0.19290.57720.67680.117*
H13C0.37810.50880.69430.117*
N10.22865 (13)0.41904 (13)0.56182 (5)0.0508 (2)
O10.35151 (9)0.27540 (10)0.48107 (4)0.0477 (2)
O20.39299 (10)0.40450 (10)0.38245 (4)0.0509 (2)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0724 (8)0.0649 (8)0.0671 (8)0.0025 (7)0.0106 (6)0.0160 (6)
C20.0435 (5)0.0577 (7)0.0495 (6)0.0018 (5)0.0009 (4)0.0032 (5)
C30.0407 (5)0.0495 (6)0.0513 (6)0.0054 (4)0.0047 (4)0.0003 (5)
C40.0375 (5)0.0529 (6)0.0461 (6)0.0011 (4)0.0045 (4)0.0026 (4)
C50.0567 (6)0.0469 (6)0.0500 (6)0.0108 (5)0.0095 (5)0.0089 (5)
C60.0930 (10)0.0516 (7)0.0778 (9)0.0049 (7)0.0270 (8)0.0136 (6)
C70.0377 (5)0.0567 (7)0.0486 (6)0.0031 (4)0.0085 (4)0.0021 (5)
C80.0502 (6)0.0623 (7)0.0587 (7)0.0030 (5)0.0096 (5)0.0005 (6)
C90.0576 (7)0.0630 (8)0.0861 (10)0.0058 (6)0.0158 (6)0.0088 (7)
C100.0706 (9)0.0835 (11)0.0808 (10)0.0003 (8)0.0211 (7)0.0279 (8)
C110.0714 (8)0.0987 (12)0.0537 (7)0.0022 (8)0.0161 (6)0.0137 (7)
C120.0497 (6)0.0738 (8)0.0497 (6)0.0029 (6)0.0122 (5)0.0002 (6)
C130.0895 (10)0.0930 (11)0.0544 (8)0.0102 (9)0.0217 (7)0.0172 (7)
N10.0514 (5)0.0556 (6)0.0455 (5)0.0050 (4)0.0079 (4)0.0035 (4)
O10.0496 (4)0.0458 (4)0.0475 (4)0.0004 (3)0.0073 (3)0.0025 (3)
O20.0523 (4)0.0504 (5)0.0517 (4)0.0042 (3)0.0136 (3)0.0022 (3)
Geometric parameters (Å, º) top
C1—C21.5048 (17)C6—H6B0.9600
C1—H1A0.9600C6—H6C0.9600
C1—H1B0.9600C7—C81.3893 (17)
C1—H1C0.9600C7—N11.4014 (15)
C2—O21.4376 (14)C7—C121.4065 (16)
C2—C31.5133 (16)C8—C91.3800 (18)
C2—H20.9800C8—H80.9300
C3—C41.5103 (16)C9—C101.371 (2)
C3—H3A0.9700C9—H90.9300
C3—H3B0.9700C10—C111.375 (2)
C4—N11.4212 (14)C10—H100.9300
C4—O11.4431 (13)C11—C121.386 (2)
C4—H40.9800C11—H110.9300
C5—O21.4108 (14)C12—C131.501 (2)
C5—O11.4122 (13)C13—H13A0.9600
C5—C61.5010 (18)C13—H13B0.9600
C5—H50.9800C13—H13C0.9600
C6—H6A0.9600N1—H10.843 (15)
C2—C1—H1A109.5C5—C6—H6C109.5
C2—C1—H1B109.5H6A—C6—H6C109.5
H1A—C1—H1B109.5H6B—C6—H6C109.5
C2—C1—H1C109.5C8—C7—N1122.26 (10)
H1A—C1—H1C109.5C8—C7—C12119.20 (11)
H1B—C1—H1C109.5N1—C7—C12118.51 (11)
O2—C2—C1107.58 (9)C9—C8—C7120.85 (12)
O2—C2—C3109.08 (8)C9—C8—H8119.6
C1—C2—C3113.24 (10)C7—C8—H8119.6
O2—C2—H2109.0C10—C9—C8120.41 (14)
C1—C2—H2109.0C10—C9—H9119.8
C3—C2—H2109.0C8—C9—H9119.8
C4—C3—C2111.04 (9)C9—C10—C11119.03 (14)
C4—C3—H3A109.4C9—C10—H10120.5
C2—C3—H3A109.4C11—C10—H10120.5
C4—C3—H3B109.4C10—C11—C12122.41 (14)
C2—C3—H3B109.4C10—C11—H11118.8
H3A—C3—H3B108.0C12—C11—H11118.8
N1—C4—O1109.70 (8)C11—C12—C7118.09 (13)
N1—C4—C3111.35 (9)C11—C12—C13121.14 (12)
O1—C4—C3109.23 (8)C7—C12—C13120.76 (12)
N1—C4—H4108.8C12—C13—H13A109.5
O1—C4—H4108.8C12—C13—H13B109.5
C3—C4—H4108.8H13A—C13—H13B109.5
O2—C5—O1111.04 (9)C12—C13—H13C109.5
O2—C5—C6108.50 (10)H13A—C13—H13C109.5
O1—C5—C6108.08 (10)H13B—C13—H13C109.5
O2—C5—H5109.7C7—N1—C4121.93 (10)
O1—C5—H5109.7C7—N1—H1115.0 (10)
C6—C5—H5109.7C4—N1—H1112.4 (10)
C5—C6—H6A109.5C5—O1—C4112.35 (8)
C5—C6—H6B109.5C5—O2—C2111.57 (8)
H6A—C6—H6B109.5
O2—C2—C3—C452.82 (11)N1—C7—C12—C130.45 (17)
C1—C2—C3—C4172.57 (9)C8—C7—N1—C44.57 (16)
C2—C3—C4—N1172.86 (8)C12—C7—N1—C4177.47 (10)
C2—C3—C4—O151.55 (11)O1—C4—N1—C765.48 (12)
N1—C7—C8—C9177.63 (11)C3—C4—N1—C7173.48 (9)
C12—C7—C8—C90.31 (17)O2—C5—O1—C460.92 (11)
C7—C8—C9—C100.9 (2)C6—C5—O1—C4179.82 (9)
C8—C9—C10—C110.5 (2)N1—C4—O1—C5177.70 (9)
C9—C10—C11—C120.5 (2)C3—C4—O1—C555.39 (11)
C10—C11—C12—C71.0 (2)O1—C5—O2—C261.96 (11)
C10—C11—C12—C13178.05 (14)C6—C5—O2—C2179.40 (9)
C8—C7—C12—C110.63 (17)C1—C2—O2—C5179.23 (9)
N1—C7—C12—C11178.65 (11)C3—C2—O2—C557.58 (11)
C8—C7—C12—C13178.47 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.843 (15)2.559 (15)3.3688 (13)161.3 (13)
C3—H3A···O1i0.972.543.4950 (13)167
Symmetry code: (i) x+1, y+1, z+1.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O2i0.843 (15)2.559 (15)3.3688 (13)161.3 (13)
C3—H3A···O1i0.972.543.4950 (13)167
Symmetry code: (i) x+1, y+1, z+1.
 

Acknowledgements

The authors thank the TBI X-ray facility, CAS in Crystallography and Biophysics, University of Madras, India, for the data collection. ZF and DV acknowledge the UGC (SAP–CAS) for the departmental facilities. ZF also thanks the UGC for a meritorious fellowship.

References

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