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

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ISSN: 2056-9890

5-Di­methyl­amino-N,N-di­methyl-2-nitro­benzamide

aX-ray Crystallography Unit, School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia, bManipal Institute of Technology, Manipal University, Manipal 576 104, India, and cDepartment of Chemistry, National Institute of Technology-Karnataka, Surathkal, Mangalore 575 025, India
*Correspondence e-mail: hkfun@usm.my

(Received 6 May 2009; accepted 13 May 2009; online 20 May 2009)

In the title compound, C11H15N3O3, one of the methyl groups attached to the benzamide unit is slightly twisted with a C—N—C—C torsion angle of 4.04 (13)°. The crystal packing is stabilized by weak intermolecular C—H⋯O hydrogen bonds together with a weak C—H⋯π inter­action.

Related literature

For nitro­aniline mustards, see: Brian et al. (1992[Brian, D. P., William, R. W., Stephen, C. & William, A. D. (1992). J. Med. Chem. 35, 3214-3222.]); Rauth, (1984[Rauth, A. M. (1984). Oncol. Biol. Phys. 10, 1293-1300.]). For N-[(N,N-dimethyl­amino)eth­yl]carboxamide derivatives, see: Alston et al. (1983[Alston, T. A., Porter, D. J. & Bright, H. J. (1983). Acc. Chem. Res. 16, 418-442.]); Denny & Wilson (1986[Denny, W. A. & Wilson, W. R. (1986). J. Med. Chem. 29, 879-887.]); Palmer et al. (1990[Palmer, B. D., Wilson, W. R., Pullen, S. M. & Denny, W. A. (1990). J. Med. Chem. 33, 112-121.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986[Cosier, J. & Glazer, A. M. (1986). J. Appl. Cryst. 19, 105-107.]).

[Scheme 1]

Experimental

Crystal data
  • C11H15N3O3

  • Mr = 237.26

  • Monoclinic, P 21

  • a = 7.8581 (2) Å

  • b = 7.2921 (2) Å

  • c = 10.5183 (3) Å

  • β = 104.663 (1)°

  • V = 583.09 (3) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.10 mm−1

  • T = 100 K

  • 0.52 × 0.45 × 0.33 mm

Data collection
  • Bruker SMART APEXII CCD area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.949, Tmax = 0.965

  • 16075 measured reflections

  • 3233 independent reflections

  • 3002 reflections with I > 2σ(I)

  • Rint = 0.027

Refinement
  • R[F2 > 2σ(F2)] = 0.038

  • wR(F2) = 0.103

  • S = 1.08

  • 3233 reflections

  • 158 parameters

  • 1 restraint

  • H-atom parameters constrained

  • Δρmax = 0.64 e Å−3

  • Δρmin = −0.19 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C8—H8A⋯O3i 0.96 2.52 3.1751 (16) 126
C10—H10A⋯O2ii 0.96 2.59 3.5413 (14) 173
C10—H10B⋯O1iii 0.96 2.49 3.3920 (13) 156
C4—H4ACg1iv 0.93 2.81 3.3991 (11) 122
Symmetry codes: (i) [-x+1, y+{\script{1\over 2}}, -z+1]; (ii) x-1, y, z; (iii) [-x, y-{\script{1\over 2}}, -z]; (iv) [-x+1, y-{\script{1\over 2}}, -z]. Cg1 is the centroid of the C1–C6 ring.

Data collection: APEX2 (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2005[Bruker (2005). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information


Comment top

Nitroaniline mustards are potential hypoxia-selective cytotoxic agents (Rauth, 1984) possessing reductive metabolism which activates the mustard nitrogen by converting the electron-withdrawing nitro group to an electron-donating hydroxylamine or amine (Brian et al., 1992). N-[(N,N-dimethylamino)ethyl]carboxamide derivatives proved to have excellent aqueous solubility and improved cytotoxic potency (Denny et al., 1986), but their reduction potentials, while higher than the non carboxamide compounds, were still low and have limited selectivity for hypoxic cells. (Palmer et al., 1990; Alston et al., 1983). These properties prompted us to synthesize the title compound.

In the asymmetric unit of (I), (Fig 1), one of the methyl group attached to the benzamide unit is slightly twisted as indicated by the torsion angle of C9–N1–C7–C6=4.04 (13)°. The benzene ring is essentially planar with the maximum deviation from planarity of 0.0117 (10)Å for the atom C5. The bond lengths and bond angles are normal (Allen et al., 1987).

The crystal packing is stabilized by intermolecular weak C—H···O hydrogen bonds together with weak C—H···π interaction (Table 1, Fig. 2).

Related literature top

For nitroaniline mustards, see: Brian et al. (1992); Rauth, (1984). For N-[(N,N-dimethylamino)ethyl]carboxamide derivatives, see: Alston et al. (1983); Denny et al. (1986); Palmer et al. (1990). For related bond-length data, see: Allen et al. (1987). For the stability of the temperature controller used in the data collection, see: Cosier & Glazer (1986). Cg1 is the centroid of the C1–C6 ring.

Experimental top

5-Fluoro-2-nitrobenzoic acid (5 g, 0.0270 mol) was heated with 40% aqueous dimethyl amine solution (50 ml) at 100°C for 18 hrs. Reaction mixture was concentrated through rotovap using high vacuum pump to afford 5-(dimethylamino)-2-nitrobenzoic acid as yellow crystalline solid (4.5 g). To a solution of 5-(dimethylamino)-2-nitrobenzoic acid (4 g, 0.019 mol) in DMF(40 ml) was added 1-(3-Dimethylaminopropyl)-3-ethyl carbodiimide hydrochloride (5.4 g, 0.0285 mol), 1-hydroxy benzotriazole (0.25 g, 0.0019 mol) and N,N-diisopropyl ethylamine (4.9 g, 0.038 mol) and the reaction mixture was stirred at room temperature for 18 hrs. Reaction mixture was portioned between 10% sodium bicarbonate solution and ethyl acetate (25 ml). The organic layer was washed with brine and dried over anhydrous sodium sulfate and concentrated through rotovap. The concentrated product were purified by column chromatography (60–120 mesh silica gel) using hexane and ethyl acetate as eluent to afford 5-(dimethylamino)-N, N-dimethyl-2-nitrobenzamide (3 g, 66.6%) as yellow crystalline solid. M.p was found to be 458–461 K.

Refinement top

H atoms were positioned geometrically [C–H = 0.93–0.96 Å] and refined using a riding model, with Uiso(H) = 1.2Ueq(C) and 1.5Ueq(methyl C). A rotating–group model was used for the methyl groups. Since there is no anamolous scattering effects, 2707 Friedel pairs were merged before final refinement.

The largest residual electron densities are located in the middle of some C-C bonds within the phenyl ring.

Computing details top

Data collection: APEX2 (Bruker, 2005); cell refinement: SAINT (Bruker, 2005); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The molecular structure of the title compound, showing 50% probability displacement ellipsoids and the atom numbering scheme.
[Figure 2] Fig. 2. The crystal packing of the title compound, viewed along the a axis. Dashed lines indicate the hydrogen bonding and C-H···π interactions.
(I) top
Crystal data top
C11H15N3O3F(000) = 252
Mr = 237.26Dx = 1.351 Mg m3
Monoclinic, P21Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ybCell parameters from 9204 reflections
a = 7.8581 (2) Åθ = 2.7–40.5°
b = 7.2921 (2) ŵ = 0.10 mm1
c = 10.5183 (3) ÅT = 100 K
β = 104.663 (1)°Block, yellow
V = 583.09 (3) Å30.52 × 0.45 × 0.33 mm
Z = 2
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3233 independent reflections
Radiation source: fine-focus sealed tube3002 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.027
ϕ and ω scansθmax = 37.5°, θmin = 2.7°
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
h = 1313
Tmin = 0.949, Tmax = 0.965k = 1212
16075 measured reflectionsl = 1818
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)] = 0.038Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.103H-atom parameters constrained
S = 1.08 w = 1/[σ2(Fo2) + (0.0716P)2 + 0.0071P]
where P = (Fo2 + 2Fc2)/3
3233 reflections(Δ/σ)max < 0.001
158 parametersΔρmax = 0.64 e Å3
1 restraintΔρmin = 0.19 e Å3
Crystal data top
C11H15N3O3V = 583.09 (3) Å3
Mr = 237.26Z = 2
Monoclinic, P21Mo Kα radiation
a = 7.8581 (2) ŵ = 0.10 mm1
b = 7.2921 (2) ÅT = 100 K
c = 10.5183 (3) Å0.52 × 0.45 × 0.33 mm
β = 104.663 (1)°
Data collection top
Bruker SMART APEXII CCD area-detector
diffractometer
3233 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2005)
3002 reflections with I > 2σ(I)
Tmin = 0.949, Tmax = 0.965Rint = 0.027
16075 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0381 restraint
wR(F2) = 0.103H-atom parameters constrained
S = 1.08Δρmax = 0.64 e Å3
3233 reflectionsΔρmin = 0.19 e Å3
158 parameters
Special details top

Experimental. The crystal was placed in the cold stream of an Oxford Cyrosystems Cobra open-flow nitrogen cryostat (Cosier & Glazer, 1986) operating at 100.0 (1) K.

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
O10.42663 (10)1.04274 (10)0.31204 (7)0.01969 (13)
O20.81992 (10)0.62755 (17)0.20077 (10)0.0334 (2)
O30.71314 (10)0.76718 (13)0.34531 (8)0.02322 (15)
N10.32548 (10)0.78907 (13)0.39646 (8)0.01811 (14)
N20.03825 (10)0.70383 (12)0.13123 (8)0.01594 (13)
N30.69532 (10)0.69824 (13)0.23538 (9)0.01899 (15)
C10.21826 (10)0.78067 (12)0.08485 (8)0.01443 (13)
H1A0.12100.83090.10720.017*
C20.19805 (10)0.70835 (12)0.04364 (9)0.01396 (13)
C30.35014 (11)0.63797 (13)0.07614 (9)0.01687 (15)
H3A0.34270.59500.16060.020*
C40.50889 (12)0.63311 (14)0.01717 (10)0.01789 (16)
H4A0.60700.58370.00450.021*
C50.52463 (11)0.70133 (13)0.14373 (9)0.01538 (14)
C60.37880 (10)0.77846 (12)0.17780 (8)0.01392 (13)
C70.38381 (11)0.87931 (13)0.30423 (8)0.01530 (14)
C80.30516 (14)0.88622 (18)0.51258 (10)0.02438 (19)
H8A0.34091.01160.50880.037*
H8B0.37700.82900.58990.037*
H8C0.18420.88220.51560.037*
C90.26858 (13)0.59813 (16)0.38621 (11)0.02241 (18)
H9A0.31490.53680.32150.034*
H9B0.14240.59300.36060.034*
H9C0.31090.53890.46980.034*
C100.11334 (12)0.79019 (15)0.10016 (10)0.02084 (17)
H10A0.12200.75030.01510.031*
H10B0.21830.75620.16500.031*
H10C0.09970.92100.09990.031*
C110.02302 (13)0.65472 (17)0.26808 (10)0.02261 (18)
H11A0.06640.53240.27240.034*
H11B0.09080.73880.30560.034*
H11C0.09820.66070.31630.034*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
O10.0221 (3)0.0166 (3)0.0198 (3)0.0026 (2)0.0044 (2)0.0016 (2)
O20.0152 (3)0.0482 (6)0.0356 (4)0.0109 (3)0.0039 (3)0.0048 (4)
O30.0180 (3)0.0286 (4)0.0212 (3)0.0001 (3)0.0016 (2)0.0009 (3)
N10.0175 (3)0.0211 (4)0.0163 (3)0.0025 (3)0.0053 (2)0.0010 (3)
N20.0142 (3)0.0169 (3)0.0162 (3)0.0002 (2)0.0029 (2)0.0020 (3)
N30.0132 (3)0.0199 (3)0.0232 (3)0.0010 (3)0.0033 (2)0.0028 (3)
C10.0119 (3)0.0156 (3)0.0163 (3)0.0001 (2)0.0045 (2)0.0015 (3)
C20.0134 (3)0.0125 (3)0.0162 (3)0.0006 (2)0.0042 (2)0.0005 (3)
C30.0154 (3)0.0165 (3)0.0198 (4)0.0002 (3)0.0065 (3)0.0033 (3)
C40.0142 (3)0.0175 (4)0.0230 (4)0.0013 (3)0.0065 (3)0.0022 (3)
C50.0117 (3)0.0151 (3)0.0191 (3)0.0008 (3)0.0036 (2)0.0010 (3)
C60.0128 (3)0.0134 (3)0.0159 (3)0.0007 (2)0.0043 (2)0.0011 (3)
C70.0131 (3)0.0175 (3)0.0150 (3)0.0004 (3)0.0029 (2)0.0003 (3)
C80.0253 (4)0.0322 (5)0.0174 (4)0.0020 (4)0.0086 (3)0.0002 (4)
C90.0205 (4)0.0228 (4)0.0232 (4)0.0045 (3)0.0041 (3)0.0059 (3)
C100.0145 (3)0.0253 (4)0.0214 (4)0.0033 (3)0.0020 (3)0.0045 (4)
C110.0208 (4)0.0303 (5)0.0164 (3)0.0019 (3)0.0040 (3)0.0045 (3)
Geometric parameters (Å, º) top
O1—C71.2354 (12)C4—C51.3969 (13)
O2—N31.2400 (12)C4—H4A0.9300
O3—N31.2358 (12)C5—C61.4021 (11)
N1—C71.3450 (12)C6—C71.5115 (13)
N1—C81.4553 (13)C8—H8A0.9600
N1—C91.4580 (14)C8—H8B0.9600
N2—C21.3569 (11)C8—H8C0.9600
N2—C101.4558 (12)C9—H9A0.9600
N2—C111.4585 (12)C9—H9B0.9600
N3—C51.4403 (12)C9—H9C0.9600
C1—C61.3868 (11)C10—H10A0.9600
C1—C21.4216 (12)C10—H10B0.9600
C1—H1A0.9300C10—H10C0.9600
C2—C31.4197 (11)C11—H11A0.9600
C3—C41.3787 (12)C11—H11B0.9600
C3—H3A0.9300C11—H11C0.9600
C7—N1—C8119.80 (9)O1—C7—N1124.11 (9)
C7—N1—C9124.61 (8)O1—C7—C6118.29 (8)
C8—N1—C9115.48 (8)N1—C7—C6117.31 (8)
C2—N2—C10120.41 (7)N1—C8—H8A109.5
C2—N2—C11120.45 (7)N1—C8—H8B109.5
C10—N2—C11117.41 (8)H8A—C8—H8B109.5
O3—N3—O2122.21 (9)N1—C8—H8C109.5
O3—N3—C5119.06 (8)H8A—C8—H8C109.5
O2—N3—C5118.74 (9)H8B—C8—H8C109.5
C6—C1—C2121.92 (7)N1—C9—H9A109.5
C6—C1—H1A119.0N1—C9—H9B109.5
C2—C1—H1A119.0H9A—C9—H9B109.5
N2—C2—C3121.23 (8)N1—C9—H9C109.5
N2—C2—C1121.07 (7)H9A—C9—H9C109.5
C3—C2—C1117.69 (7)H9B—C9—H9C109.5
C4—C3—C2120.20 (8)N2—C10—H10A109.5
C4—C3—H3A119.9N2—C10—H10B109.5
C2—C3—H3A119.9H10A—C10—H10B109.5
C3—C4—C5121.00 (8)N2—C10—H10C109.5
C3—C4—H4A119.5H10A—C10—H10C109.5
C5—C4—H4A119.5H10B—C10—H10C109.5
C4—C5—C6120.36 (8)N2—C11—H11A109.5
C4—C5—N3118.37 (7)N2—C11—H11B109.5
C6—C5—N3121.20 (8)H11A—C11—H11B109.5
C1—C6—C5118.75 (8)N2—C11—H11C109.5
C1—C6—C7115.54 (7)H11A—C11—H11C109.5
C5—C6—C7125.39 (7)H11B—C11—H11C109.5
C10—N2—C2—C3174.89 (9)C2—C1—C6—C50.44 (13)
C11—N2—C2—C310.25 (14)C2—C1—C6—C7173.36 (8)
C10—N2—C2—C16.32 (14)C4—C5—C6—C11.86 (13)
C11—N2—C2—C1170.96 (9)N3—C5—C6—C1178.85 (8)
C6—C1—C2—N2176.85 (9)C4—C5—C6—C7171.28 (9)
C6—C1—C2—C31.98 (13)N3—C5—C6—C75.71 (14)
N2—C2—C3—C4175.78 (9)C8—N1—C7—O11.74 (14)
C1—C2—C3—C43.05 (13)C9—N1—C7—O1177.67 (9)
C2—C3—C4—C51.73 (15)C8—N1—C7—C6171.90 (8)
C3—C4—C5—C60.79 (15)C9—N1—C7—C64.04 (13)
C3—C4—C5—N3177.86 (9)C1—C6—C7—O191.10 (10)
O3—N3—C5—C4176.11 (9)C5—C6—C7—O182.24 (12)
O2—N3—C5—C43.35 (14)C1—C6—C7—N182.91 (10)
O3—N3—C5—C60.94 (14)C5—C6—C7—N1103.75 (10)
O2—N3—C5—C6179.61 (10)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8A···O3i0.962.523.1751 (16)126
C10—H10A···O2ii0.962.593.5413 (14)173
C10—H10B···O1iii0.962.493.3920 (13)156
C4—H4A···Cg1iv0.932.813.3991 (11)122
Symmetry codes: (i) x+1, y+1/2, z+1; (ii) x1, y, z; (iii) x, y1/2, z; (iv) x+1, y1/2, z.

Experimental details

Crystal data
Chemical formulaC11H15N3O3
Mr237.26
Crystal system, space groupMonoclinic, P21
Temperature (K)100
a, b, c (Å)7.8581 (2), 7.2921 (2), 10.5183 (3)
β (°) 104.663 (1)
V3)583.09 (3)
Z2
Radiation typeMo Kα
µ (mm1)0.10
Crystal size (mm)0.52 × 0.45 × 0.33
Data collection
DiffractometerBruker SMART APEXII CCD area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2005)
Tmin, Tmax0.949, 0.965
No. of measured, independent and
observed [I > 2σ(I)] reflections
16075, 3233, 3002
Rint0.027
(sin θ/λ)max1)0.857
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.038, 0.103, 1.08
No. of reflections3233
No. of parameters158
No. of restraints1
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.64, 0.19

Computer programs: APEX2 (Bruker, 2005), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C8—H8A···O3i0.962.523.1751 (16)126
C10—H10A···O2ii0.962.593.5413 (14)173
C10—H10B···O1iii0.962.493.3920 (13)156
C4—H4A···Cg1iv0.932.813.3991 (11)122
Symmetry codes: (i) x+1, y+1/2, z+1; (ii) x1, y, z; (iii) x, y1/2, z; (iv) x+1, y1/2, z.
 

Footnotes

Thomson Reuters Researcher ID: A-3561-2009.

§Thomson Reuters Researcher ID: A-5473-2009. Permanent address: Department of Physics, Karunya University, Karunya Nagar, Coimbatore 641 114, India.

Acknowledgements

HKF and SRJ thank the Malaysian Government and Universiti Sains Malaysia for the Science Fund grant No. 305/PFIZIK/613312. SRJ thanks Universiti Sains Malaysia for a post–doctoral research fellowship. HKF also thanks Universiti Sains Malaysia for the Research University Golden Goose grant No. 1001/PFIZIK/811012. AMI is grateful to the Head of the Chemistry Department and the Director, NITK, Surathkal, India, for providing research facilities.

References

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