organic compounds
2-Methyl-N-p-tolylbenzamide: a second monoclinic polymorph
aDepartment of Chemistry, Quaid-i-Azam University, Islamabad 45320, Pakistan, and bDepartment of Chemistry, University of Otago, PO Box 56, Dunedin, New Zealand
*Correspondence e-mail: aamersaeed@yahoo.com
The title compound, C15H15NO, (I), is a polymorph of the structure (II) reported by Gowda et al. [Acta Cryst. (2008), E64, o1494]. Compound (II) crystalllizes in the C2/c (Z = 8), whereas the title compound occurs in P21/c (Z = 4). The two molecular structures differ slightly in the relative orientations of their central amide group with respect to the benzoyl ring [dihedral angles of 55.99 (7) for (I) and 59.96 (11)° for (II)] and in the inclination of the benzoyl and aniline rings [88.67 (8) for (I) and 81.44 (5)° for (II)]. In the of (I), molecules are linked by N—H⋯O hydrogen bonds, forming C(4) chains, which are augmented by weak C—H⋯O interactions. The structure is further stabilized by C—H⋯π contacts involving both of the aromatic rings.
Related literature
For the biological activity of N-substituted benzamides, see: Olsson et al. (2002); Lindgren et al. (2001). For the use of heterocyclic analogs of benzanilide derivatives as potassium channel activators, see: Calderone et al. (2006). For the use of 2-nitrobenzamides in organic synthesis, see: Zhichkin et al. (2007); Beccalli et al. (2005). For the original monoclinic polymorph, see: Gowda et al. (2008). For the related N-(2,4-dimethylphenyl)-2-methylbenzamide, see: Gowda et al. (2009). For hydrogen-bond motifs, see: Bernstein et al. (1995).
Experimental
Crystal data
|
Refinement
|
Data collection: APEX2 (Bruker, 2006); cell APEX2 and SAINT (Bruker, 2006); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97, enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2010).
Supporting information
10.1107/S1600536810010378/hb5364sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536810010378/hb5364Isup2.hkl
2-Methylbenzoyl chloride (1 mmol) in CHCl3 was treated with 4-methylaniline (3.5 mmol) under a nitrogen atmosphere at reflux for 3.5 h. Upon cooling, the reaction mixture was diluted with CHCl3 and washed consecutively with 1 M aq HCl and saturated aq NaHCO3. The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure. Crystallization of the residue from ethanol afforded colourless plates of (I) in 78% yield: Anal. calcd. for C15H25NO: C, 79.97; H, 6.71; N, 6.22; found: C, 80.06; H, 6.87; N, 6.01%
The H atom bound to N1 was located in a difference map and refined isotropically. All other H-atoms were positioned geometrically and refined using a riding model with d(C—H) = 0.95 Å, Uiso = 1.2Ueq (C) for aromatic and d(C—H) = 0.98 Å, Uiso = 1.5Ueq (C) for methyl C atoms. Crystals were very thin and weakly diffracting. Even with 60 s scans over 24 h, no useful data was observed beyond theta = 20.71 °.
Data collection: APEX2 (Bruker, 2006); cell
APEX2 and SAINT (Bruker, 2006); data reduction: SAINT (Bruker, 2006); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2010).C15H15NO | F(000) = 480 |
Mr = 225.28 | Dx = 1.195 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 1469 reflections |
a = 20.259 (3) Å | θ = 3.1–20.2° |
b = 7.0681 (10) Å | µ = 0.08 mm−1 |
c = 8.7941 (13) Å | T = 89 K |
β = 95.942 (9)° | Rectangular plate, colourless |
V = 1252.5 (3) Å3 | 0.30 × 0.19 × 0.06 mm |
Z = 4 |
Bruker APEXII CCD diffractometer | 1283 independent reflections |
Radiation source: fine-focus sealed tube | 1028 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.052 |
ω scans | θmax = 20.7°, θmin = 1.0° |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | h = −20→20 |
Tmin = 0.803, Tmax = 1.000 | k = −7→7 |
8447 measured reflections | l = −8→8 |
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)] = 0.040 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.108 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | w = 1/[σ2(Fo2) + (0.0571P)2 + 0.3937P] where P = (Fo2 + 2Fc2)/3 |
1283 reflections | (Δ/σ)max = 0.002 |
159 parameters | Δρmax = 0.16 e Å−3 |
0 restraints | Δρmin = −0.23 e Å−3 |
C15H15NO | V = 1252.5 (3) Å3 |
Mr = 225.28 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 20.259 (3) Å | µ = 0.08 mm−1 |
b = 7.0681 (10) Å | T = 89 K |
c = 8.7941 (13) Å | 0.30 × 0.19 × 0.06 mm |
β = 95.942 (9)° |
Bruker APEXII CCD diffractometer | 1283 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | 1028 reflections with I > 2σ(I) |
Tmin = 0.803, Tmax = 1.000 | Rint = 0.052 |
8447 measured reflections | θmax = 20.7° |
R[F2 > 2σ(F2)] = 0.040 | 0 restraints |
wR(F2) = 0.108 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.07 | Δρmax = 0.16 e Å−3 |
1283 reflections | Δρmin = −0.23 e Å−3 |
159 parameters |
Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds 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 | ||
N1 | 0.73575 (10) | 0.2686 (3) | 0.6898 (2) | 0.0250 (6) | |
H1N | 0.7455 (11) | 0.297 (3) | 0.789 (3) | 0.030* | |
O1 | 0.76424 (8) | 0.0912 (2) | 0.48978 (19) | 0.0301 (5) | |
C1 | 0.77164 (12) | 0.1340 (3) | 0.6268 (3) | 0.0231 (7) | |
C2 | 0.82221 (12) | 0.0392 (3) | 0.7367 (3) | 0.0207 (7) | |
C3 | 0.88871 (13) | 0.0342 (3) | 0.7074 (3) | 0.0232 (7) | |
C31 | 0.91234 (13) | 0.1250 (4) | 0.5675 (3) | 0.0327 (7) | |
H31A | 0.8943 | 0.0557 | 0.4760 | 0.049* | |
H31B | 0.9609 | 0.1217 | 0.5753 | 0.049* | |
H31C | 0.8972 | 0.2567 | 0.5602 | 0.049* | |
C4 | 0.93384 (13) | −0.0562 (3) | 0.8148 (3) | 0.0269 (7) | |
H4 | 0.9795 | −0.0597 | 0.7988 | 0.032* | |
C5 | 0.91342 (14) | −0.1405 (3) | 0.9437 (3) | 0.0302 (7) | |
H5 | 0.9450 | −0.2013 | 1.0149 | 0.036* | |
C6 | 0.84744 (13) | −0.1368 (3) | 0.9697 (3) | 0.0285 (7) | |
H6 | 0.8334 | −0.1961 | 1.0579 | 0.034* | |
C7 | 0.80182 (12) | −0.0460 (3) | 0.8663 (3) | 0.0239 (7) | |
H7 | 0.7564 | −0.0419 | 0.8840 | 0.029* | |
C8 | 0.68730 (12) | 0.3892 (4) | 0.6124 (3) | 0.0230 (7) | |
C9 | 0.68482 (12) | 0.5755 (4) | 0.6619 (3) | 0.0278 (7) | |
H9 | 0.7146 | 0.6179 | 0.7455 | 0.033* | |
C10 | 0.63886 (13) | 0.6993 (4) | 0.5893 (3) | 0.0330 (7) | |
H10 | 0.6381 | 0.8270 | 0.6228 | 0.040* | |
C11 | 0.59398 (13) | 0.6409 (4) | 0.4687 (3) | 0.0327 (8) | |
C111 | 0.54250 (14) | 0.7756 (4) | 0.3928 (3) | 0.0466 (9) | |
H11A | 0.5237 | 0.7223 | 0.2949 | 0.070* | |
H11B | 0.5634 | 0.8975 | 0.3751 | 0.070* | |
H11C | 0.5071 | 0.7939 | 0.4594 | 0.070* | |
C12 | 0.59739 (13) | 0.4542 (4) | 0.4208 (3) | 0.0345 (8) | |
H12 | 0.5677 | 0.4116 | 0.3370 | 0.041* | |
C13 | 0.64310 (12) | 0.3286 (4) | 0.4923 (3) | 0.0285 (7) | |
H13 | 0.6440 | 0.2009 | 0.4588 | 0.034* |
U11 | U22 | U33 | U12 | U13 | U23 | |
N1 | 0.0360 (14) | 0.0248 (14) | 0.0135 (12) | 0.0036 (11) | −0.0006 (11) | −0.0010 (11) |
O1 | 0.0457 (12) | 0.0259 (11) | 0.0182 (12) | 0.0017 (9) | 0.0006 (9) | −0.0010 (8) |
C1 | 0.0349 (17) | 0.0173 (16) | 0.0170 (17) | −0.0079 (13) | 0.0029 (13) | −0.0008 (12) |
C2 | 0.0319 (17) | 0.0133 (14) | 0.0163 (15) | 0.0013 (12) | −0.0004 (13) | −0.0022 (12) |
C3 | 0.0354 (18) | 0.0108 (14) | 0.0232 (16) | 0.0002 (12) | 0.0020 (13) | −0.0042 (12) |
C31 | 0.0396 (17) | 0.0253 (17) | 0.0341 (17) | −0.0008 (13) | 0.0079 (13) | 0.0024 (13) |
C4 | 0.0317 (16) | 0.0177 (16) | 0.0309 (18) | 0.0009 (12) | 0.0015 (13) | −0.0073 (13) |
C5 | 0.042 (2) | 0.0206 (16) | 0.0259 (18) | 0.0066 (13) | −0.0043 (14) | −0.0010 (13) |
C6 | 0.046 (2) | 0.0204 (16) | 0.0196 (16) | 0.0028 (13) | 0.0045 (14) | 0.0034 (12) |
C7 | 0.0310 (16) | 0.0193 (15) | 0.0214 (16) | 0.0020 (12) | 0.0018 (13) | −0.0006 (12) |
C8 | 0.0278 (15) | 0.0261 (17) | 0.0154 (15) | 0.0022 (13) | 0.0034 (13) | 0.0045 (13) |
C9 | 0.0325 (16) | 0.0289 (18) | 0.0217 (16) | 0.0044 (13) | 0.0020 (13) | −0.0007 (13) |
C10 | 0.0418 (18) | 0.0284 (17) | 0.0299 (17) | 0.0083 (14) | 0.0088 (15) | 0.0023 (14) |
C11 | 0.0317 (17) | 0.040 (2) | 0.0267 (17) | 0.0069 (14) | 0.0062 (14) | 0.0112 (14) |
C111 | 0.0442 (19) | 0.054 (2) | 0.0430 (19) | 0.0141 (16) | 0.0079 (15) | 0.0182 (16) |
C12 | 0.0324 (17) | 0.043 (2) | 0.0271 (17) | −0.0043 (14) | −0.0004 (13) | 0.0054 (14) |
C13 | 0.0330 (16) | 0.0273 (17) | 0.0252 (17) | −0.0013 (14) | 0.0020 (14) | 0.0045 (13) |
N1—C1 | 1.351 (3) | C6—H6 | 0.9500 |
N1—C8 | 1.420 (3) | C7—H7 | 0.9500 |
N1—H1N | 0.90 (3) | C8—C13 | 1.380 (3) |
O1—C1 | 1.236 (3) | C8—C9 | 1.389 (3) |
C1—C2 | 1.493 (3) | C9—C10 | 1.385 (3) |
C2—C7 | 1.389 (3) | C9—H9 | 0.9500 |
C2—C3 | 1.398 (3) | C10—C11 | 1.387 (4) |
C3—C4 | 1.399 (3) | C10—H10 | 0.9500 |
C3—C31 | 1.509 (4) | C11—C12 | 1.389 (4) |
C31—H31A | 0.9800 | C11—C111 | 1.515 (4) |
C31—H31B | 0.9800 | C111—H11A | 0.9800 |
C31—H31C | 0.9800 | C111—H11B | 0.9800 |
C4—C5 | 1.381 (4) | C111—H11C | 0.9800 |
C4—H4 | 0.9500 | C12—C13 | 1.386 (4) |
C5—C6 | 1.380 (4) | C12—H12 | 0.9500 |
C5—H5 | 0.9500 | C13—H13 | 0.9500 |
C6—C7 | 1.386 (3) | ||
C1—N1—C8 | 126.9 (2) | C6—C7—C2 | 120.3 (2) |
C1—N1—H1N | 118.9 (16) | C6—C7—H7 | 119.8 |
C8—N1—H1N | 113.8 (16) | C2—C7—H7 | 119.8 |
O1—C1—N1 | 123.8 (2) | C13—C8—C9 | 119.5 (2) |
O1—C1—C2 | 121.8 (2) | C13—C8—N1 | 122.8 (2) |
N1—C1—C2 | 114.4 (2) | C9—C8—N1 | 117.7 (2) |
C7—C2—C3 | 121.0 (2) | C10—C9—C8 | 119.9 (2) |
C7—C2—C1 | 118.9 (2) | C10—C9—H9 | 120.0 |
C3—C2—C1 | 120.1 (2) | C8—C9—H9 | 120.0 |
C2—C3—C4 | 117.5 (2) | C9—C10—C11 | 121.4 (3) |
C2—C3—C31 | 122.2 (2) | C9—C10—H10 | 119.3 |
C4—C3—C31 | 120.3 (2) | C11—C10—H10 | 119.3 |
C3—C31—H31A | 109.5 | C10—C11—C12 | 117.8 (2) |
C3—C31—H31B | 109.5 | C10—C11—C111 | 121.1 (3) |
H31A—C31—H31B | 109.5 | C12—C11—C111 | 121.1 (3) |
C3—C31—H31C | 109.5 | C11—C111—H11A | 109.5 |
H31A—C31—H31C | 109.5 | C11—C111—H11B | 109.5 |
H31B—C31—H31C | 109.5 | H11A—C111—H11B | 109.5 |
C5—C4—C3 | 121.4 (2) | C11—C111—H11C | 109.5 |
C5—C4—H4 | 119.3 | H11A—C111—H11C | 109.5 |
C3—C4—H4 | 119.3 | H11B—C111—H11C | 109.5 |
C6—C5—C4 | 120.4 (2) | C13—C12—C11 | 121.5 (2) |
C6—C5—H5 | 119.8 | C13—C12—H12 | 119.2 |
C4—C5—H5 | 119.8 | C11—C12—H12 | 119.2 |
C5—C6—C7 | 119.4 (2) | C8—C13—C12 | 119.9 (3) |
C5—C6—H6 | 120.3 | C8—C13—H13 | 120.0 |
C7—C6—H6 | 120.3 | C12—C13—H13 | 120.0 |
C8—N1—C1—O1 | −3.8 (4) | C3—C2—C7—C6 | 0.4 (3) |
C8—N1—C1—C2 | 175.9 (2) | C1—C2—C7—C6 | 179.3 (2) |
O1—C1—C2—C7 | −124.6 (3) | C1—N1—C8—C13 | 38.7 (4) |
N1—C1—C2—C7 | 55.7 (3) | C1—N1—C8—C9 | −141.7 (2) |
O1—C1—C2—C3 | 54.3 (3) | C13—C8—C9—C10 | −0.9 (4) |
N1—C1—C2—C3 | −125.4 (2) | N1—C8—C9—C10 | 179.4 (2) |
C7—C2—C3—C4 | −1.3 (3) | C8—C9—C10—C11 | 1.1 (4) |
C1—C2—C3—C4 | 179.8 (2) | C9—C10—C11—C12 | −1.2 (4) |
C7—C2—C3—C31 | 179.9 (2) | C9—C10—C11—C111 | 178.2 (2) |
C1—C2—C3—C31 | 1.0 (3) | C10—C11—C12—C13 | 1.2 (4) |
C2—C3—C4—C5 | 1.1 (3) | C111—C11—C12—C13 | −178.1 (2) |
C31—C3—C4—C5 | −180.0 (2) | C9—C8—C13—C12 | 1.0 (4) |
C3—C4—C5—C6 | −0.2 (4) | N1—C8—C13—C12 | −179.4 (2) |
C4—C5—C6—C7 | −0.7 (4) | C11—C12—C13—C8 | −1.1 (4) |
C5—C6—C7—C2 | 0.6 (4) |
Cg1 and Cg2 are the centroids of the C3–C7 and C8–C13 benzene rings, repectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O1i | 0.90 (3) | 1.94 (3) | 2.821 (3) | 169 (2) |
C9—H9···O1i | 0.95 | 2.71 | 3.366 (3) | 127 |
C7—H7···Cg2ii | 0.95 | 2.84 | 3.751 (3) | 160 |
C31—H31C···Cg1iii | 0.98 | 2.86 | 3.676 (3) | 141 |
Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) x, −y+1/2, z−3/2; (iii) x, −y+1/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C15H15NO |
Mr | 225.28 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 89 |
a, b, c (Å) | 20.259 (3), 7.0681 (10), 8.7941 (13) |
β (°) | 95.942 (9) |
V (Å3) | 1252.5 (3) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.08 |
Crystal size (mm) | 0.30 × 0.19 × 0.06 |
Data collection | |
Diffractometer | Bruker APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2006) |
Tmin, Tmax | 0.803, 1.000 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 8447, 1283, 1028 |
Rint | 0.052 |
θmax (°) | 20.7 |
(sin θ/λ)max (Å−1) | 0.498 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.040, 0.108, 1.07 |
No. of reflections | 1283 |
No. of parameters | 159 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.16, −0.23 |
Computer programs: APEX2 (Bruker, 2006), APEX2 and SAINT (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and TITAN2000 (Hunter & Simpson, 1999), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2008), SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2010).
Cg1 and Cg2 are the centroids of the C3–C7 and C8–C13 benzene rings, repectively. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O1i | 0.90 (3) | 1.94 (3) | 2.821 (3) | 169 (2) |
C9—H9···O1i | 0.95 | 2.71 | 3.366 (3) | 127 |
C7—H7···Cg2ii | 0.95 | 2.84 | 3.751 (3) | 160 |
C31—H31C···Cg1iii | 0.98 | 2.86 | 3.676 (3) | 141 |
Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) x, −y+1/2, z−3/2; (iii) x, −y+1/2, z−1/2. |
Acknowledgements
The authors gratefully acknowledge a research grant from the Higher Education Commission of Pakistan, project No.20-Miscel/R&D/00/3834. We also thank the University of Otago for the purchase of the diffractometer.
References
Allen, F. H., Johnson, O., Shields, G. P., Smith, B. R. & Towler, M. (2004). J. Appl. Cryst. 37, 335–338. Web of Science CrossRef CAS IUCr Journals Google Scholar
Beccalli, E. M., Broggini, G., Paladinoa, G. & Zonia, C. (2005). Tetrahedron, 61, 61–68. Web of Science CrossRef CAS Google Scholar
Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573. CrossRef CAS Web of Science Google Scholar
Bruker (2006). APEX2, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Calderone, V., Fiamingo, F. L., Giorgi, I., Leonardi, M., Livi, O., Martelli, A. & Martinotti, E. (2006). Eur. J. Med. Chem. 41, 761–767. Web of Science CrossRef PubMed CAS Google Scholar
Gowda, B. T., Tokarčík, M., Kožíšek, J., Rodrigues, V. Z. & Fuess, H. (2009). Acta Cryst. E65, o826. Web of Science CSD CrossRef IUCr Journals Google Scholar
Gowda, B. T., Tokarčík, M., Kožíšek, J., Sowmya, B. P. & Fuess, H. (2008). Acta Cryst. E64, o1494. Web of Science CSD CrossRef IUCr Journals Google Scholar
Hunter, K. A. & Simpson, J. (1999). TITAN2000. University of Otago, New Zealand. Google Scholar
Lindgren, H., Pero, R. W., Ivars, F. & Leanderson, T. (2001). Mol. Immunol. 38, 267–277. Web of Science CrossRef PubMed CAS Google Scholar
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. Web of Science CrossRef CAS IUCr Journals Google Scholar
Olsson, A. R., Lindgren, H., Pero, R. W. & Leanderson, T. (2002). Br. J. Cancer, 86, 971–978. Web of Science CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2008). Acta Cryst. A64, 112–122. Web of Science CrossRef CAS IUCr Journals Google Scholar
Spek, A. L. (2009). Acta Cryst. D65, 148–155. Web of Science CrossRef CAS IUCr Journals Google Scholar
Westrip, S. P. (2010). publCIF. In preparation. Google Scholar
Zhichkin, P., Kesicki, E., Treiberg, J., Bourdon, L., Ronsheim, M., Ooi, H. C., White, S., Judkins, A. & Fairfax, D. (2007). Org. Lett. 9, 1415–1418. Web of Science CrossRef PubMed CAS Google Scholar
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.
N-substituted benzamides are well known anticancer compounds and the mechanism of action for N-substituted benzamide-induced apoptosis has been studied, using declopramide as a lead compound (Olsson et al., 2002). N-substituted benzamides inhibit the activity of nuclear factor- B and nuclear factor T cell activity while inducing activator protein 1 activity in T lymphocytes (Lindgren et al., 2001). Heterocyclic analogs of benzanilide derivatives are potassium channel activators (Calderone et al., 2006). N-alkylated 2-nitrobenzamides are intermediates in the synthesis of dibenzo[b,e][1,4]diazepines (Zhichkin et al., 2007) and N-acyl-2-nitrobenzamides are precursors of 2,3-disubstitued 3H-quinazoline-4-ones (Beccalli et al., 2005).
The title compound, (I), is a second monoclinic polymorph of the structure of this benzamide derivative which crystallises in the space group P21/c. An alternative structure, II, in the space group C2/c was reported previously by Gowda et al., (2008). The major structural differences between the two polymorphs lie in the orientations of their central C2,C1,O1,N1,C8 amide groups with respect to the C2···C6 benzoyl ring. In I the N1–C1–C2–C7 dihedral angle is 55.69 (3) for (I) whereas for (II) it is -60.69 (18). Furthermore the angle between the plane through C2,C1,O1,N1,C8 and the C2···C6 ring plane is 55.99 (7)/% in (I) but 59.96 (11) for (II) and the two phenyl rings are respectively inclined at 88.67 (8)/% for (I) and 81.44 (5)/% for (II). Bond distances in the molecule are normal and comparable to those in the second polymorph and in a closely related benzamide derivative (Gowda et al., 2009).
In the crystal structure intermolecular N1–H1···O1 hydrogen bonds form C(4) chains down the c axis (Bernstein et al. 1995). These chains are further stabilised by weak C9–H9···O1 interactions and C–H···π contacts involving both the aniline and benzoyl ring systems.