supplementary materials


lh5388 scheme

Acta Cryst. (2012). E68, o180-o181    [ doi:10.1107/S1600536811053554 ]

6-Ethyl-N-methyl-3-nitro-4-nitromethyl-4H-chromen-2-amine

J. Muthukumaran, A. Parthiban, H. Surya Prakash Rao and R. Krishna

Abstract top

In the title compound, C13H15N3O5, the O and N atoms of the nitromethyl group and the methyl C atom of the ethyl group are disordered over two sets of sites with refined occupancies of 0.629 (7):0.371 (7) and 0.533 (8):0.467 (8), respectively. The dihydropyran ring has an extremely flattened conformation. An intramolecular N-H...O hydrogen bond occurs. In the crystal, pairs of N-H...O hydrogen bonds link molecules, forming inversion dimers. In addition, weak intermolecular C-H...O hydrogen bonds are also present.

Comment top

The 4H-chromene moiety frequently appears as a main structural component in various biologically important compounds. They exhibit the various pharmacological properties such as anti-coagulant, anti-viral, anti-fungal, anti-inflammatory, anti-diabetic and anti-cancer activity (Cai, 2008; Cai, 2007; Cai et al., 2006; Gabor et al., 1988; Brooks, 1998; Hyana & Saimoto, 1987; Tang et al., 2007). Considering the growing medicinal importance of these derivatives, an X-ray crystallographic study on the title compound was carried out. In the molecular structure of the title compound (I) (Fig. 1) the O and N atoms of the nitromethyl group and the methyl C atom of the ethyl group are disordered over two sets of sites with refined occupancies of 0.629 (7):0.371 (7) and 0.533 (8):0.467 (8), respectively. Some crystal structures of related 4H-chromene derivatives have already been published e.g. N-methyl-3-nitro-4-(nitromethyl)-4H-chromen-2-amine (Muthukumaran et al., 2011c), 6,8-dichloro-N-methyl-3-nitro-4-nitro-methyl-4H-chromen-2-amine (Muthukumaran et al., 2011a), 6-methoxy-N-methyl-3-nitro-4-nitromethyl-4H-chromen-2-amine (Muthukumaran et al., 2011b), N-benzyl-N-[4-methylsulfanyl)-3-nitro-4H-chromen-2-yl] amine (Bhaskaran et al., 2006) and N,6-dimethyl-4-(methylsulfanyl)-3-nitro-4H-chromen-2-amine (Gayathri et al., 2006). In the crystal, N—H···O hydrogen bonds form centrosymmetric dimers (Fig .2). In addition, there are weak intermolecular C—H···O hydrogen bonds.

Related literature top

For the biological and pharmacological importance of 4H-chromene derivatives, see: Cai (2007, 2008); Cai et al. (2006); Gabor et al. (1988); Brooks (1998); Hyana & Saimoto (1987); Tang et al. (2007). For related structures, see: Muthukumaran et al. (2011a,b,c); Gayathri et al. (2006); Bhaskaran et al. (2006).

Experimental top

To a solution of (E)-5-ethyl-2-(2-nitrovinyl)phenol (150 mg, 0.77 mmol) in methanol (5 mL), 1,8-diazabicyclo[5.4.0]undec-7-ene (15 mg, 0.10 mmol) was added and stirred for 10 minutes at room temperature. To this solution (E) N-methyl-1-(methylthio)-2-nitroethenamine (115 mg, 0.77 mmol) was added and stirred for 8 h until completion of the reaction (TLC, hexane:ethyl acetate, 3:2, Rf = 1/2). The reaction mixture was then kept aside at 278 K in a refrigerator for 3 h to afford racemic mixture of the product as a white precipitate, which was filtered. Good crystals were obtained by recrystallization of a solution of dichloromethane: hexane (9:3 v/v).

Refinement top

H atoms were positioned geometrically (C—H = 0.93–0.98 Å. N—H = 0.86Å) and were refined using a riding model with Uiso(H) = xUeq(C,N), where x = 1.5 for methyl and 1.2 for all other atoms. The nitro and terminal carbon atom of ethyl group are disordered over two orientations, with the refined site-occupancy ratios being 0.629 (7):0.371 (7) and 0.533 (8):0.467 (8), respectively. The DFIX, SIMU, DELU and EADP commands in SHELXL (Sheldrick, 2008) were used to model the disorder.

Computing details top

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: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. : The molecular structure of (I), showing displacement ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. : The crystal packing of (I) showing intermolecular hydrogen bonds as dashed lines.
6-Ethyl-N-methyl-3-nitro-4-nitromethyl-4H-chromen-2-amine top
Crystal data top
C13H15N3O5Z = 2
Mr = 293.28F(000) = 308
Triclinic, P1Dx = 1.388 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.71073 Å
a = 8.2538 (10) ÅCell parameters from 1935 reflections
b = 9.0431 (9) Åθ = 2.7–29.1°
c = 10.3323 (12) ŵ = 0.11 mm1
α = 73.484 (9)°T = 293 K
β = 71.728 (11)°Block, colorless
γ = 83.234 (9)°0.4 × 0.35 × 0.2 mm
V = 701.75 (14) Å3
Data collection top
Oxford Diffraction Xcalibur Eos
diffractometer
2463 independent reflections
Radiation source: fine-focus sealed tube1520 reflections with I > 2σ(I)
graphiteRint = 0.031
Detector resolution: 15.9821 pixels mm-1θmax = 25.0°, θmin = 2.7°
ω scansh = 99
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
k = 1010
Tmin = 0.958, Tmax = 0.979l = 1112
4281 measured reflections
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.073Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.232H-atom parameters constrained
S = 1.06 w = 1/[σ2(Fo2) + (0.1377P)2 + 0.1022P]
where P = (Fo2 + 2Fc2)/3
2463 reflections(Δ/σ)max < 0.001
205 parametersΔρmax = 0.40 e Å3
122 restraintsΔρmin = 0.34 e Å3
Crystal data top
C13H15N3O5γ = 83.234 (9)°
Mr = 293.28V = 701.75 (14) Å3
Triclinic, P1Z = 2
a = 8.2538 (10) ÅMo Kα radiation
b = 9.0431 (9) ŵ = 0.11 mm1
c = 10.3323 (12) ÅT = 293 K
α = 73.484 (9)°0.4 × 0.35 × 0.2 mm
β = 71.728 (11)°
Data collection top
Oxford Diffraction Xcalibur Eos
diffractometer
2463 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Oxford Diffraction, 2009)
1520 reflections with I > 2σ(I)
Tmin = 0.958, Tmax = 0.979Rint = 0.031
4281 measured reflectionsθmax = 25.0°
Refinement top
R[F2 > 2σ(F2)] = 0.073H-atom parameters constrained
wR(F2) = 0.232Δρmax = 0.40 e Å3
S = 1.06Δρmin = 0.34 e Å3
2463 reflectionsAbsolute structure: ?
205 parametersFlack parameter: ?
122 restraintsRogers parameter: ?
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*/UeqOcc. (<1)
O10.4139 (2)0.2857 (3)1.1942 (2)0.0468 (6)
C10.5007 (4)0.2700 (4)1.0581 (3)0.0401 (8)
C80.6569 (4)0.4021 (4)1.1982 (3)0.0383 (8)
O20.6415 (3)0.5176 (3)1.3724 (2)0.0569 (7)
O30.8792 (3)0.5209 (3)1.2039 (2)0.0636 (8)
N20.7266 (3)0.4819 (3)1.2608 (3)0.0435 (7)
C90.4856 (4)0.3561 (4)1.2598 (3)0.0394 (8)
N10.3831 (3)0.3738 (3)1.3790 (3)0.0490 (8)
H10.42240.41671.42670.059*
C60.6684 (4)0.3088 (4)0.9922 (3)0.0380 (8)
C20.4066 (4)0.2138 (4)0.9941 (4)0.0490 (9)
H20.29350.18771.04080.059*
C50.7416 (4)0.2899 (4)0.8563 (3)0.0489 (9)
H50.85510.31510.80990.059*
C70.7700 (4)0.3607 (4)1.0681 (3)0.0413 (8)
H70.82380.45631.00440.050*
C40.6519 (5)0.2354 (4)0.7888 (4)0.0528 (9)
C30.4833 (5)0.1970 (4)0.8600 (4)0.0548 (10)
H30.42090.15920.81600.066*
C110.9145 (4)0.2466 (4)1.0924 (4)0.0588 (10)
H11A0.99640.24401.00210.071*
H11B0.97260.28041.14680.071*
N3A0.8506 (10)0.0891 (5)1.1687 (9)0.085 (2)0.629 (7)
O4A0.7196 (14)0.0755 (17)1.2654 (17)0.113 (3)0.629 (7)
O5A0.9064 (12)0.0297 (9)1.1366 (11)0.169 (3)0.629 (7)
N3B0.8580 (16)0.0962 (10)1.1944 (16)0.085 (2)0.371 (7)
O4B0.717 (2)0.043 (3)1.240 (3)0.113 (3)0.371 (7)
O5B0.9759 (19)0.0179 (16)1.2268 (18)0.169 (3)0.371 (7)
C120.7376 (6)0.2240 (6)0.6386 (4)0.0778 (13)
H12A0.72790.32460.57510.093*0.533 (8)
H12B0.85810.20080.62770.093*0.533 (8)
H12C0.65500.25060.58570.093*0.467 (8)
H12D0.82860.29700.59320.093*0.467 (8)
C13A0.6702 (15)0.1062 (12)0.5913 (10)0.114 (3)0.533 (8)
H13A0.73340.10970.49510.171*0.533 (8)
H13B0.55170.12910.59830.171*0.533 (8)
H13C0.68280.00500.65060.171*0.533 (8)
C13B0.8100 (18)0.0627 (8)0.6369 (12)0.114 (3)0.467 (8)
H13D0.86360.05830.54110.171*0.467 (8)
H13E0.71970.00940.68040.171*0.467 (8)
H13F0.89290.03690.68810.171*0.467 (8)
C100.2057 (4)0.3261 (6)1.4383 (4)0.0722 (13)
H10A0.13800.39121.38250.108*
H10B0.16240.33501.53360.108*
H10C0.20010.22091.43760.108*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0348 (11)0.0592 (17)0.0485 (13)0.0089 (10)0.0032 (9)0.0247 (11)
C10.0371 (16)0.041 (2)0.0445 (17)0.0043 (14)0.0130 (14)0.0158 (14)
C80.0367 (16)0.039 (2)0.0394 (16)0.0034 (13)0.0094 (13)0.0109 (14)
O20.0646 (15)0.0694 (19)0.0409 (12)0.0110 (13)0.0074 (11)0.0262 (12)
O30.0457 (14)0.085 (2)0.0667 (16)0.0271 (13)0.0008 (12)0.0383 (15)
N20.0472 (16)0.0450 (18)0.0393 (14)0.0071 (12)0.0081 (12)0.0155 (13)
C90.0362 (16)0.0365 (19)0.0431 (17)0.0004 (13)0.0080 (14)0.0114 (14)
N10.0431 (15)0.058 (2)0.0448 (15)0.0076 (13)0.0022 (12)0.0255 (14)
C60.0404 (17)0.0360 (19)0.0386 (16)0.0007 (13)0.0114 (13)0.0126 (14)
C20.0420 (18)0.050 (2)0.063 (2)0.0021 (15)0.0210 (16)0.0223 (18)
C50.0472 (18)0.051 (2)0.0468 (19)0.0022 (16)0.0073 (15)0.0175 (16)
C70.0361 (16)0.047 (2)0.0416 (17)0.0084 (14)0.0050 (13)0.0173 (15)
C40.064 (2)0.052 (2)0.0476 (19)0.0046 (17)0.0212 (17)0.0185 (17)
C30.066 (2)0.050 (2)0.063 (2)0.0010 (18)0.0350 (19)0.0208 (18)
C110.0356 (17)0.080 (3)0.074 (2)0.0052 (17)0.0169 (16)0.042 (2)
N3A0.075 (3)0.079 (3)0.095 (4)0.044 (2)0.033 (2)0.023 (2)
O4A0.131 (3)0.045 (7)0.154 (7)0.008 (3)0.030 (3)0.021 (4)
O5A0.189 (6)0.098 (5)0.222 (9)0.055 (5)0.065 (5)0.065 (5)
N3B0.075 (3)0.079 (3)0.095 (4)0.044 (2)0.033 (2)0.023 (2)
O4B0.131 (3)0.045 (7)0.154 (7)0.008 (3)0.030 (3)0.021 (4)
O5B0.189 (6)0.098 (5)0.222 (9)0.055 (5)0.065 (5)0.065 (5)
C120.100 (3)0.084 (3)0.056 (2)0.003 (3)0.022 (2)0.031 (2)
C13A0.168 (10)0.096 (6)0.073 (5)0.015 (6)0.000 (5)0.049 (4)
C13B0.168 (10)0.096 (6)0.073 (5)0.015 (6)0.000 (5)0.049 (4)
C100.046 (2)0.092 (4)0.073 (3)0.015 (2)0.0122 (19)0.041 (2)
Geometric parameters (Å, °) top
O1—C91.342 (4)C11—N3B1.4847 (11)
O1—C11.403 (3)C11—N3A1.4847 (11)
C1—C61.375 (4)C11—H11A0.9700
C1—C21.380 (4)C11—H11B0.9700
C8—N21.366 (4)N3A—O4A1.2113 (11)
C8—C91.414 (4)N3A—O5A1.2115 (11)
C8—C71.496 (4)N3B—O4B1.2114 (11)
O2—N21.256 (3)N3B—O5B1.2117 (11)
O3—N21.256 (3)C12—C13B1.5122 (11)
C9—N11.298 (4)C12—C13A1.5125 (11)
N1—C101.463 (4)C12—H12A0.9700
N1—H10.8600C12—H12B0.9700
C6—C51.395 (4)C12—H12C0.9700
C6—C71.501 (4)C12—H12D0.9700
C2—C31.376 (5)C13A—H13A0.9600
C2—H20.9300C13A—H13B0.9600
C5—C41.372 (5)C13A—H13C0.9600
C5—H50.9300C13B—H13D0.9600
C7—C111.517 (5)C13B—H13E0.9600
C7—H70.9800C13B—H13F0.9600
C4—C31.387 (5)C10—H10A0.9600
C4—C121.518 (5)C10—H10B0.9600
C3—H30.9300C10—H10C0.9600
C9—O1—C1120.9 (2)O4A—N3A—O5A114.3 (8)
C6—C1—C2122.1 (3)O4A—N3A—C11118.5 (9)
C6—C1—O1122.2 (3)O5A—N3A—C11126.8 (8)
C2—C1—O1115.7 (3)O4B—N3B—O5B118.9 (19)
N2—C8—C9120.1 (3)O4B—N3B—C11128.9 (19)
N2—C8—C7117.6 (2)O5B—N3B—C11112.1 (11)
C9—C8—C7122.2 (3)C13B—C12—C13A53.2 (7)
O3—N2—O2119.8 (3)C13B—C12—C4110.9 (5)
O3—N2—C8118.7 (2)C13A—C12—C4116.9 (5)
O2—N2—C8121.5 (3)C13B—C12—H12A141.0
N1—C9—O1113.2 (3)C13A—C12—H12A108.1
N1—C9—C8126.7 (3)C4—C12—H12A108.1
O1—C9—C8120.1 (3)C13B—C12—H12B59.8
C9—N1—C10125.0 (3)C13A—C12—H12B108.1
C9—N1—H1117.5C4—C12—H12B108.1
C10—N1—H1117.5H12A—C12—H12B107.3
C1—C6—C5117.5 (3)C13B—C12—H12C109.5
C1—C6—C7120.6 (3)C13A—C12—H12C57.4
C5—C6—C7121.8 (3)C4—C12—H12C109.5
C3—C2—C1118.7 (3)H12A—C12—H12C56.1
C3—C2—H2120.6H12B—C12—H12C142.2
C1—C2—H2120.6C13B—C12—H12D109.5
C4—C5—C6122.2 (3)C13A—C12—H12D133.6
C4—C5—H5118.9C4—C12—H12D109.5
C6—C5—H5118.9H12A—C12—H12D55.3
C8—C7—C6111.4 (2)H12B—C12—H12D53.9
C8—C7—C11114.3 (3)H12C—C12—H12D108.0
C6—C7—C11111.6 (3)C12—C13A—H13A109.5
C8—C7—H7106.3C12—C13A—H13B109.5
C6—C7—H7106.3H13A—C13A—H13B109.5
C11—C7—H7106.3C12—C13A—H13C109.5
C5—C4—C3118.2 (3)H13A—C13A—H13C109.5
C5—C4—C12119.3 (3)H13B—C13A—H13C109.5
C3—C4—C12122.5 (3)C12—C13B—H13D109.5
C2—C3—C4121.4 (3)C12—C13B—H13E109.5
C2—C3—H3119.3H13D—C13B—H13E109.5
C4—C3—H3119.3C12—C13B—H13F109.5
N3B—C11—C7114.4 (6)H13D—C13B—H13F109.5
N3A—C11—C7111.4 (4)H13E—C13B—H13F109.5
N3B—C11—H11A117.3N1—C10—H10A109.5
N3A—C11—H11A109.3N1—C10—H10B109.5
C7—C11—H11A109.3H10A—C10—H10B109.5
N3B—C11—H11B97.5N1—C10—H10C109.5
N3A—C11—H11B109.3H10A—C10—H10C109.5
C7—C11—H11B109.3H10B—C10—H10C109.5
H11A—C11—H11B108.0
C9—O1—C1—C67.7 (5)C1—C6—C7—C814.8 (4)
C9—O1—C1—C2172.0 (3)C5—C6—C7—C8168.7 (3)
C9—C8—N2—O3179.8 (3)C1—C6—C7—C11114.3 (3)
C7—C8—N2—O32.4 (4)C5—C6—C7—C1162.2 (4)
C9—C8—N2—O20.7 (5)C6—C5—C4—C30.6 (5)
C7—C8—N2—O2178.2 (3)C6—C5—C4—C12177.5 (3)
C1—O1—C9—N1174.0 (3)C1—C2—C3—C40.0 (5)
C1—O1—C9—C86.3 (4)C5—C4—C3—C20.4 (6)
N2—C8—C9—N14.2 (5)C12—C4—C3—C2177.5 (4)
C7—C8—C9—N1173.1 (3)C8—C7—C11—N3B59.4 (9)
N2—C8—C9—O1176.1 (3)C6—C7—C11—N3B68.2 (9)
C7—C8—C9—O16.6 (5)C8—C7—C11—N3A72.3 (5)
O1—C9—N1—C101.1 (5)C6—C7—C11—N3A55.3 (5)
C8—C9—N1—C10179.2 (4)N3B—C11—N3A—O4A65 (4)
C2—C1—C6—C50.3 (5)C7—C11—N3A—O4A41.2 (12)
O1—C1—C6—C5179.4 (3)N3B—C11—N3A—O5A123 (4)
C2—C1—C6—C7176.3 (3)C7—C11—N3A—O5A131.0 (10)
O1—C1—C6—C74.0 (5)N3A—C11—N3B—O4B64 (4)
C6—C1—C2—C30.4 (5)C7—C11—N3B—O4B15 (2)
O1—C1—C2—C3179.3 (3)N3A—C11—N3B—O5B112 (4)
C1—C6—C5—C40.2 (5)C7—C11—N3B—O5B169.6 (13)
C7—C6—C5—C4176.8 (3)C5—C4—C12—C13B96.2 (7)
N2—C8—C7—C6166.3 (3)C3—C4—C12—C13B85.9 (8)
C9—C8—C7—C616.4 (4)C5—C4—C12—C13A154.5 (7)
N2—C8—C7—C1166.0 (4)C3—C4—C12—C13A27.5 (8)
C9—C8—C7—C11111.3 (3)
Hydrogen-bond geometry (Å, °) top
D—H···AD—HH···AD···AD—H···A
N1—H1···O20.861.972.600 (3)129
N1—H1···O2i0.862.212.943 (4)143
C11—H11A···O3ii0.972.583.258 (4)128
C12—H12A···O2iii0.972.553.457 (5)156
Symmetry codes: (i) −x+1, −y+1, −z+3; (ii) −x+2, −y+1, −z+2; (iii) x, y, z−1.
Table 1
Hydrogen-bond geometry (Å, °)
top
D—H···AD—HH···AD···AD—H···A
N1—H1···O20.861.972.600 (3)129
N1—H1···O2i0.862.212.943 (4)143
C11—H11A···O3ii0.972.583.258 (4)128
C12—H12A···O2iii0.972.553.457 (5)156
Symmetry codes: (i) −x+1, −y+1, −z+3; (ii) −x+2, −y+1, −z+2; (iii) x, y, z−1.
Acknowledgements top

JM thanks the Council for Scientific and Industrial Research (CSIR) for a Senior Research Fellowship (SRF). RK thanks the Centre for Bioinformatics (funded by the Department of Biotechnology and Department of Information Technology, New Delhi, India), Pondicherry University, for providing the computational facilities to carry out this research work. AP thanks Pondicherry University for a fellowship. HSPR thanks the UGC (University Grant Commission) for the Special Assistance Programme (SAP) and the Department of Science and Technology (DST) for the Fund for Improvement of Science and Technology Infrastructure in Universities and Higher Educational Institutions (FIST).

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