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

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ISSN: 2056-9890

N-(2,6-Di­methyl­phen­yl)-2-methyl­benzamide

aDepartment of Chemistry, Mangalore University, Mangalagangotri 574 199, Mangalore, India, and bInstitute of Materials Science, Darmstadt University of Technology, Petersenstrasse 23, D-64287 Darmstadt, Germany
*Correspondence e-mail: gowdabt@yahoo.com

(Received 13 June 2008; accepted 22 July 2008; online 26 July 2008)

In the title mol­ecule, C16H17NO, the N—H and C=O groups are in the anti­periplanar conformation that has been observed in related compounds. Furthermore, the conformation of the C=O group with respect to the methyl substituent in the 2-methyl­phenyl ring is syn, as has also been observed in related structures. The amide group makes dihedral angles of 50.3 (3) and 64.6 (3)° with the 2-methyl­phenyl and 2,6-dimethyl­phenyl rings, respectively, while the angle between the planes of the two rings is 14.26 (7)°. The mol­ecules are packed into chains via N—H⋯O hydrogen bonds. An intramolecular C—H⋯O hydrogen bond is also observed.

Related literature

For related literature, see: Gowda et al. (2003[Gowda, B. T., Jyothi, K., Paulus, H. & Fuess, H. (2003). Z. Naturforsch. Teil A, 58, 225-230.]); Gowda, Foro et al. (2008[Gowda, B. T., Foro, S., Sowmya, B. P. & Fuess, H. (2008). Acta Cryst. E64, o383.]); Gowda, Tokarčík et al. (2008[Gowda, B. T., Tokarčík, M., Kožíšek, J., Sowmya, B. P. & Fuess, H. (2008). Acta Cryst. E64, o1299.]).

[Scheme 1]

Experimental

Crystal data
  • C16H17NO

  • Mr = 239.31

  • Orthorhombic, P b c a

  • a = 11.687 (1) Å

  • b = 10.0187 (8) Å

  • c = 22.108 (2) Å

  • V = 2588.6 (4) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.08 mm−1

  • T = 100 (2) K

  • 0.36 × 0.24 × 0.04 mm

Data collection
  • Oxford Xcalibur diffractometer with Sapphire CCD detector

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis RED. Oxford Diffraction Ltd., Köln, Germany.]) Tmin = 0.971, Tmax = 0.999

  • 10773 measured reflections

  • 2624 independent reflections

  • 1864 reflections with I > 2σ(I)

  • Rint = 0.024

Refinement
  • R[F2 > 2σ(F2)] = 0.036

  • wR(F2) = 0.127

  • S = 1.00

  • 2624 reflections

  • 169 parameters

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

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N⋯O1i 0.917 (17) 2.012 (17) 2.9248 (15) 173.7 (14)
C15—H15A⋯O1 0.98 2.53 3.1170 (17) 118
Symmetry code: (i) [-x+{\script{3\over 2}}, y-{\script{1\over 2}}, z].

Data collection: CrysAlis CCD (Oxford Diffraction, 2004[Oxford Diffraction (2004). CrysAlis CCD. Oxford Diffraction Ltd., Köln, Germany.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2007[Oxford Diffraction (2007). CrysAlis RED. Oxford Diffraction Ltd., Köln, Germany.]); data reduction: CrysAlis RED; 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.]) and JANA2000 (Petříček et al., 2000[Petříček, V., Dušek, M. & Palatinus, L. (2000). JANA2000. Institute of Physics, Czech Academy of Sciences, Prague, Czech Republic.]); molecular graphics: PLATON (Spek, 2003[Spek, A. L. (2003). J. Appl. Cryst. 36, 7-13.]); software used to prepare material for publication: SHELXS97.

Supporting information


Comment top

In the present work, the structure of 2-methyl-N-(2,6-dimethylphenyl)-benzamide (N26DMP2MBA) has been determined in order to explore the effect of the substituents on the structures of benzanilides (Gowda et al., 2003; Gowda, Foro et al., 2008; Gowda, Tokarčík et al., 2008). In the structure of the title compound (N26DMP2MBA) (Fig. 1), the N—H and CO groups are in antiperiplanar conformation. This conformation is similar to the conformations in the already determined structures, e.g. in 2-methyl-N-(phenyl)-benzamide (NP2MBA) (Gowda, Foro et al., 2008); in 2-methyl-N-(2-methylphenyl)-benzamide (N2MP2MBA) and in N-(2,6-dimethylphenyl)-benzamide (N26DMPBA) (Gowda, Tokarčík et al., 2008). Further, in the title compound N26DMP2MBA, the conformation of the CO group to the methyl substituent in the 2-methylphenyl ring is syn. This conformation is similar to those observed in NP2MBA and N2MP2MBA. The bond distances and angles in N26DMP2MBA are similar to those in NP2MBA, N2MP2MBA, N26DMPBA and other benzanilides (Gowda et al., 2003; Gowda, Foro et al., 2008; Gowda, Tokarčík et al., 2008). The amide group makes the dihedral angles equal to 50.3 (3)° and 64.6 (3)° with the 2-methylphenyl and 2,6-dimethylphenyl rings, respectively, while the angle between the planes of both rings is 14.26 (7)°. In the crystal structure, the molecules are linked into chains via intermolecular N—H···O hydrogen bonds (Table 1). These chains are parallel to the a axis (Fig. 2).

Related literature top

For related literature, see: Gowda et al. (2003); Gowda, Foro et al. (2008); Gowda, Tokarčík et al. (2008).

Experimental top

The title compound was prepared according to the method described by Gowda et al. (2003). The purity of the compound was checked by determining its melting point (136°C). The title compound was also characterized by recording its infrared and NMR spectra. Plate-like colourless layered crystals with edges in the range from 0.2 to 1.0 mm were obtained by slow evaporation at room temperature from an ethanol solution (0.5 g of the title compound in about 40 ml of ethanol).

Refinement top

All the hydrogen atoms could have been discerned in the difference Fourier map, nevertheless, all the H atoms attached to the carbon atoms were constrained in a riding motion approximation with Caryl—H = 0.95, Cmethyl—H = 0.98 Å, while UisoH = 1.2UeqC. The positional parameters of HN were refined freely. UisoHN = 1.2UeqN. Five not matching reflections (2 0 0; 2 1 1; 1 0 2; 1 1 2; 1 1 3) were omitted from the refinement since their |Fo-Fc)|/σ(Fo)>100 (Petříček et al., 2000).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2004); cell refinement: CrysAlis RED (Oxford Diffraction, 2007); data reduction: CrysAlis RED (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and JANA2000 (Petříček et al., 2000); molecular graphics: PLATON (Spek, 2003); software used to prepare material for publication: SHELXS97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound, showing the atom labelling scheme. The displacement ellipsoids are drawn at the 50% probability level. The H atoms are represented as small spheres of arbitrary radii.
[Figure 2] Fig. 2. Molecular packing of the title compound with hydrogen bonding shown as dashed lines.
N-(2,6-Dimethylphenyl)-2-methylbenzamide top
Crystal data top
C16H17NODx = 1.228 Mg m3
Mr = 239.31Melting point: 409 K
Orthorhombic, PbcaMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2abCell parameters from 4403 reflections
a = 11.687 (1) Åθ = 2.2–28.0°
b = 10.0187 (8) ŵ = 0.08 mm1
c = 22.108 (2) ÅT = 100 K
V = 2588.6 (4) Å3Plate, colourless
Z = 80.36 × 0.24 × 0.04 mm
F(000) = 1024
Data collection top
Oxford Xcalibur
diffractometer with Sapphire CCD detector
2624 independent reflections
Radiation source: fine-focus sealed tube1864 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.024
Rotation method data acquisition using ω and ϕ scansθmax = 26.4°, θmin = 2.8°
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2007)
h = 1414
Tmin = 0.971, Tmax = 0.999k = 1112
10773 measured reflectionsl = 2727
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)] = 0.037Hydrogen site location: difference Fourier map
wR(F2) = 0.127H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.0871P)2 + 0.016P]
where P = (Fo2 + 2Fc2)/3
2624 reflections(Δ/σ)max < 0.001
169 parametersΔρmax = 0.27 e Å3
0 restraintsΔρmin = 0.21 e Å3
62 constraints
Crystal data top
C16H17NOV = 2588.6 (4) Å3
Mr = 239.31Z = 8
Orthorhombic, PbcaMo Kα radiation
a = 11.687 (1) ŵ = 0.08 mm1
b = 10.0187 (8) ÅT = 100 K
c = 22.108 (2) Å0.36 × 0.24 × 0.04 mm
Data collection top
Oxford Xcalibur
diffractometer with Sapphire CCD detector
2624 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2007)
1864 reflections with I > 2σ(I)
Tmin = 0.971, Tmax = 0.999Rint = 0.024
10773 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0370 restraints
wR(F2) = 0.127H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.27 e Å3
2624 reflectionsΔρmin = 0.21 e Å3
169 parameters
Special details top

Experimental. CrysAlis RED, Oxford Diffraction Ltd., 2007 Empirical absorption correction using spherical harmonics, implemented in SCALE3 ABSPACK scaling algorithm.

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
C10.66409 (12)0.10525 (13)0.52066 (6)0.0192 (3)
C20.71926 (13)0.06605 (13)0.46747 (6)0.0220 (3)
C30.66617 (14)0.09420 (15)0.41272 (7)0.0286 (4)
H30.70310.07070.37600.034*
C40.56017 (15)0.15594 (14)0.41088 (7)0.0311 (4)
H40.52530.17530.37310.037*
C50.50550 (13)0.18914 (14)0.46372 (7)0.0275 (4)
H50.43190.22910.46200.033*
C60.55589 (12)0.16532 (13)0.52008 (6)0.0214 (3)
C70.76049 (11)0.17701 (13)0.61334 (6)0.0188 (3)
C80.83330 (12)0.13044 (13)0.66513 (6)0.0204 (3)
C90.81566 (13)0.17869 (13)0.72420 (7)0.0238 (3)
C100.88936 (13)0.13316 (14)0.76907 (7)0.0302 (4)
H100.87750.16220.80950.036*
C110.97939 (14)0.04706 (16)0.75717 (7)0.0318 (4)
H111.02850.01880.78890.038*
C120.99719 (13)0.00269 (15)0.69892 (8)0.0298 (4)
H121.05960.05490.69010.036*
C130.92333 (13)0.04273 (14)0.65328 (7)0.0244 (3)
H130.93420.01000.61340.029*
C140.83131 (13)0.00795 (15)0.46972 (7)0.0277 (4)
H14A0.82170.09040.49300.033*
H14B0.88930.04820.48910.033*
H14C0.85580.02980.42850.033*
C150.49430 (12)0.20052 (15)0.57709 (7)0.0270 (4)
H15A0.52740.28200.59430.032*
H15B0.50190.12730.60620.032*
H15C0.41310.21540.56820.032*
C160.72240 (14)0.27522 (16)0.73949 (7)0.0319 (4)
H16A0.65420.25450.71550.038*
H16B0.74790.36620.73040.038*
H16C0.70400.26820.78260.038*
O10.74295 (8)0.29638 (10)0.60380 (4)0.0221 (3)
N10.71980 (10)0.07909 (12)0.57731 (5)0.0198 (3)
H1N0.7370 (13)0.0079 (17)0.5864 (7)0.024*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0241 (7)0.0121 (7)0.0214 (7)0.0040 (6)0.0027 (6)0.0008 (5)
C20.0294 (8)0.0141 (7)0.0226 (8)0.0037 (6)0.0004 (6)0.0003 (5)
C30.0437 (10)0.0198 (8)0.0223 (7)0.0024 (7)0.0011 (7)0.0009 (6)
C40.0469 (10)0.0206 (8)0.0259 (8)0.0016 (8)0.0131 (7)0.0003 (6)
C50.0293 (8)0.0167 (7)0.0364 (9)0.0004 (7)0.0101 (7)0.0005 (6)
C60.0247 (7)0.0128 (7)0.0266 (8)0.0047 (6)0.0035 (6)0.0012 (6)
C70.0199 (7)0.0159 (8)0.0208 (7)0.0020 (6)0.0058 (6)0.0001 (6)
C80.0243 (7)0.0141 (7)0.0228 (8)0.0052 (6)0.0003 (6)0.0029 (5)
C90.0284 (7)0.0180 (7)0.0251 (8)0.0050 (6)0.0010 (6)0.0009 (6)
C100.0403 (9)0.0270 (8)0.0235 (8)0.0038 (7)0.0063 (7)0.0011 (6)
C110.0337 (8)0.0290 (8)0.0326 (9)0.0019 (7)0.0136 (7)0.0053 (7)
C120.0266 (8)0.0256 (8)0.0372 (10)0.0017 (7)0.0050 (7)0.0027 (7)
C130.0280 (8)0.0184 (7)0.0267 (8)0.0009 (7)0.0011 (6)0.0009 (6)
C140.0339 (8)0.0245 (8)0.0246 (8)0.0035 (7)0.0050 (7)0.0006 (6)
C150.0242 (7)0.0223 (8)0.0346 (9)0.0002 (7)0.0030 (7)0.0012 (6)
C160.0402 (9)0.0327 (9)0.0227 (8)0.0003 (8)0.0003 (7)0.0037 (7)
O10.0275 (6)0.0139 (5)0.0250 (6)0.0004 (4)0.0020 (4)0.0014 (4)
N10.0260 (6)0.0142 (6)0.0193 (6)0.0019 (5)0.0025 (5)0.0018 (5)
Geometric parameters (Å, º) top
C1—C21.397 (2)C9—C161.496 (2)
C1—C61.400 (2)C10—C111.386 (2)
C1—N11.4357 (17)C10—H100.9500
C2—C31.389 (2)C11—C121.378 (2)
C2—C141.506 (2)C11—H110.9500
C3—C41.385 (2)C12—C131.387 (2)
C3—H30.9500C12—H120.9500
C4—C51.372 (2)C13—H130.9500
C4—H40.9500C14—H14A0.9800
C5—C61.399 (2)C14—H14B0.9800
C5—H50.9500C14—H14C0.9800
C6—C151.494 (2)C15—H15A0.9800
C7—O11.2316 (17)C15—H15B0.9800
C7—N11.3502 (18)C15—H15C0.9800
C7—C81.5009 (19)C16—H16A0.9800
C8—C131.396 (2)C16—H16B0.9800
C8—C91.408 (2)C16—H16C0.9800
C9—C101.391 (2)N1—H1N0.917 (17)
C2—C1—C6121.98 (13)C12—C11—C10119.52 (14)
C2—C1—N1118.27 (12)C12—C11—H11120.2
C6—C1—N1119.73 (12)C10—C11—H11120.2
C3—C2—C1118.04 (13)C11—C12—C13119.50 (15)
C3—C2—C14121.15 (13)C11—C12—H12120.2
C1—C2—C14120.78 (12)C13—C12—H12120.2
C4—C3—C2121.05 (14)C12—C13—C8120.98 (14)
C4—C3—H3119.5C12—C13—H13119.5
C2—C3—H3119.5C8—C13—H13119.5
C5—C4—C3119.97 (14)C2—C14—H14A109.5
C5—C4—H4120.0C2—C14—H14B109.5
C3—C4—H4120.0H14A—C14—H14B109.5
C4—C5—C6121.39 (14)C2—C14—H14C109.5
C4—C5—H5119.3H14A—C14—H14C109.5
C6—C5—H5119.3H14B—C14—H14C109.5
C5—C6—C1117.49 (13)C6—C15—H15A109.5
C5—C6—C15120.57 (13)C6—C15—H15B109.5
C1—C6—C15121.93 (12)H15A—C15—H15B109.5
O1—C7—N1123.09 (13)C6—C15—H15C109.5
O1—C7—C8121.79 (12)H15A—C15—H15C109.5
N1—C7—C8115.08 (12)H15B—C15—H15C109.5
C13—C8—C9120.04 (13)C9—C16—H16A109.5
C13—C8—C7118.69 (12)C9—C16—H16B109.5
C9—C8—C7121.19 (12)H16A—C16—H16B109.5
C10—C9—C8117.28 (14)C9—C16—H16C109.5
C10—C9—C16120.15 (13)H16A—C16—H16C109.5
C8—C9—C16122.57 (13)H16B—C16—H16C109.5
C11—C10—C9122.62 (14)C7—N1—C1122.80 (12)
C11—C10—H10118.7C7—N1—H1N118.9 (10)
C9—C10—H10118.7C1—N1—H1N117.7 (10)
C6—C1—C2—C33.1 (2)N1—C7—C8—C9132.73 (14)
N1—C1—C2—C3178.62 (12)C13—C8—C9—C101.3 (2)
C6—C1—C2—C14175.18 (12)C7—C8—C9—C10178.09 (12)
N1—C1—C2—C143.1 (2)C13—C8—C9—C16178.58 (14)
C1—C2—C3—C41.8 (2)C7—C8—C9—C161.8 (2)
C14—C2—C3—C4176.51 (13)C8—C9—C10—C112.0 (2)
C2—C3—C4—C50.6 (2)C16—C9—C10—C11177.92 (14)
C3—C4—C5—C61.8 (2)C9—C10—C11—C120.7 (2)
C4—C5—C6—C10.5 (2)C10—C11—C12—C131.3 (2)
C4—C5—C6—C15179.17 (13)C11—C12—C13—C81.9 (2)
C2—C1—C6—C52.0 (2)C9—C8—C13—C120.6 (2)
N1—C1—C6—C5179.75 (12)C7—C8—C13—C12176.27 (13)
C2—C1—C6—C15176.66 (13)O1—C7—N1—C17.7 (2)
N1—C1—C6—C151.6 (2)C8—C7—N1—C1169.99 (11)
O1—C7—C8—C13127.30 (14)C2—C1—N1—C7112.35 (15)
N1—C7—C8—C1350.44 (17)C6—C1—N1—C769.34 (18)
O1—C7—C8—C949.54 (19)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O1i0.917 (17)2.012 (17)2.9248 (15)173.7 (14)
C15—H15A···O10.982.533.1170 (17)118
Symmetry code: (i) x+3/2, y1/2, z.

Experimental details

Crystal data
Chemical formulaC16H17NO
Mr239.31
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)100
a, b, c (Å)11.687 (1), 10.0187 (8), 22.108 (2)
V3)2588.6 (4)
Z8
Radiation typeMo Kα
µ (mm1)0.08
Crystal size (mm)0.36 × 0.24 × 0.04
Data collection
DiffractometerOxford Xcalibur
diffractometer with Sapphire CCD detector
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2007)
Tmin, Tmax0.971, 0.999
No. of measured, independent and
observed [I > 2σ(I)] reflections
10773, 2624, 1864
Rint0.024
(sin θ/λ)max1)0.625
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.037, 0.127, 1.00
No. of reflections2624
No. of parameters169
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.27, 0.21

Computer programs: CrysAlis CCD (Oxford Diffraction, 2004), CrysAlis RED (Oxford Diffraction, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and JANA2000 (Petříček et al., 2000), PLATON (Spek, 2003).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O1i0.917 (17)2.012 (17)2.9248 (15)173.7 (14)
C15—H15A···O10.982.533.1170 (17)118
Symmetry code: (i) x+3/2, y1/2, z.
 

Acknowledgements

BTG thanks the Alexander von Humboldt Foundation, Bonn, Germany, for extensions of his research fellowship.

References

First citationGowda, B. T., Foro, S., Sowmya, B. P. & Fuess, H. (2008). Acta Cryst. E64, o383.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationGowda, B. T., Jyothi, K., Paulus, H. & Fuess, H. (2003). Z. Naturforsch. Teil A, 58, 225–230.  CAS Google Scholar
First citationGowda, B. T., Tokarčík, M., Kožíšek, J., Sowmya, B. P. & Fuess, H. (2008). Acta Cryst. E64, o1299.  Web of Science CSD CrossRef IUCr Journals Google Scholar
First citationOxford Diffraction (2004). CrysAlis CCD. Oxford Diffraction Ltd., Köln, Germany.  Google Scholar
First citationOxford Diffraction (2007). CrysAlis RED. Oxford Diffraction Ltd., Köln, Germany.  Google Scholar
First citationPetříček, V., Dušek, M. & Palatinus, L. (2000). JANA2000. Institute of Physics, Czech Academy of Sciences, Prague, Czech Republic.  Google Scholar
First citationSheldrick, G. M. (2008). Acta Cryst. A64, 112–122.  Web of Science CrossRef CAS IUCr Journals Google Scholar
First citationSpek, A. L. (2003). J. Appl. Cryst. 36, 7–13.  Web of Science CrossRef CAS IUCr Journals Google Scholar

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