organic compounds
2,4-Dichloro-N-o-tolylbenzamide
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
In the title compound, C14H11Cl2NO, the central C—C(O)—N—C amide unit makes dihedral angles of 68.71 (11) and 54.92 (12)°, respectively, with the dichlorobenzene and tolyl rings. The two aromatic rings are inclined at 16.25 (17)°. In the crystal, N—H⋯O hydrogen bonds link molecules into zigzag chains propagating in [001]. C—H⋯Cl contacts link these chains and additional C—H⋯O contacts generate stacks down b. Weak C—H⋯π and C—Cl⋯π interactions [Cl⋯centroid distance = 3.5422 (15) Å] may also stabilize the structure.
Related literature
For the biological activity of benzamide derivatives, see: Saeed et al. (2008a). For related structures, see: Gowda et al. (2008); Saeed et al. (2008b); Zhou & Zheng (2007). For reference structural data, see: Allen et al. (1987).
Experimental
Crystal data
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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., 2006); software used to prepare material for publication: SHELXL97, enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2009).
Supporting information
10.1107/S1600536809022752/tk2478sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809022752/tk2478Isup2.hkl
2,4-Dichlorobenzoyl chloride (5.4 mmol) in CHCl3 was treated with 2-methylaniline (21.6 mmol) under a nitrogen atmosphere at reflux for 3 h. Upon cooling, the reaction mixture was diluted with CHCl3 and washed consecutively with aq. 1 M HCl and saturated aq. NaHCO3. The organic layer was dried over anhydrous sodium sulfate and concentrated under reduced pressure. Crystallization of the residue in CHCl3 afforded (I) (81%) as colourless crystals: Anal. calcd. for C14H11Cl2NO: C 60.02, H 3.96, N 5.00%; found: C 60.05, H 3.97, N 4.97%.
All H-atoms were positioned geometrically and refined using a riding model with d(C—H) = 0.95 Å, Uiso=1.2Ueq (C) for aromatic 0.98 Å, Uiso = 1.5Ueq (C) for CH3 atoms and 0.88 Å, Uiso = 1.2Ueq (N) for the NH group. In the final electron density maps, peaks in excess of 1.0 e Å-3 were found approximately 0.8 Å from both Cl atoms but no obvious chemical significance could be attached to them; there was no obvious evidence for disorder involving the Cl atoms.
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 TITAN (Hunter & Simpson, 1999); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2009).C14H11Cl2NO | F(000) = 576 |
Mr = 280.14 | Dx = 1.469 Mg m−3 |
Monoclinic, Cc | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: C -2yc | Cell parameters from 5253 reflections |
a = 22.517 (4) Å | θ = 2.2–32.4° |
b = 6.0405 (9) Å | µ = 0.50 mm−1 |
c = 9.6332 (17) Å | T = 92 K |
β = 104.838 (9)° | Block, colourless |
V = 1266.6 (4) Å3 | 0.46 × 0.27 × 0.19 mm |
Z = 4 |
Bruker APEXII CCD diffractometer | 3475 independent reflections |
Radiation source: fine-focus sealed tube | 3195 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.043 |
ω scans | θmax = 33.1°, θmin = 1.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | h = −34→33 |
Tmin = 0.615, Tmax = 0.91 | k = −9→8 |
9889 measured reflections | l = −12→14 |
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.057 | H-atom parameters constrained |
wR(F2) = 0.158 | w = 1/[σ2(Fo2) + (0.0952P)2 + 1.0992P] where P = (Fo2 + 2Fc2)/3 |
S = 1.15 | (Δ/σ)max < 0.001 |
3475 reflections | Δρmax = 1.36 e Å−3 |
164 parameters | Δρmin = −0.62 e Å−3 |
2 restraints | Absolute structure: Flack (1983), 1248 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.05 (8) |
C14H11Cl2NO | V = 1266.6 (4) Å3 |
Mr = 280.14 | Z = 4 |
Monoclinic, Cc | Mo Kα radiation |
a = 22.517 (4) Å | µ = 0.50 mm−1 |
b = 6.0405 (9) Å | T = 92 K |
c = 9.6332 (17) Å | 0.46 × 0.27 × 0.19 mm |
β = 104.838 (9)° |
Bruker APEXII CCD diffractometer | 3475 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | 3195 reflections with I > 2σ(I) |
Tmin = 0.615, Tmax = 0.91 | Rint = 0.043 |
9889 measured reflections |
R[F2 > 2σ(F2)] = 0.057 | H-atom parameters constrained |
wR(F2) = 0.158 | Δρmax = 1.36 e Å−3 |
S = 1.15 | Δρmin = −0.62 e Å−3 |
3475 reflections | Absolute structure: Flack (1983), 1248 Friedel pairs |
164 parameters | Absolute structure parameter: 0.05 (8) |
2 restraints |
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. |
x | y | z | Uiso*/Ueq | ||
O1 | 0.16543 (13) | 0.5847 (4) | 0.3277 (3) | 0.0250 (5) | |
C1 | 0.17020 (14) | 0.5816 (5) | 0.2022 (3) | 0.0185 (5) | |
C2 | 0.22063 (13) | 0.7094 (5) | 0.1617 (3) | 0.0172 (5) | |
C3 | 0.28213 (14) | 0.6506 (5) | 0.2168 (3) | 0.0173 (5) | |
Cl1 | 0.30103 (4) | 0.41955 (12) | 0.32639 (7) | 0.02356 (18) | |
C4 | 0.32950 (13) | 0.7736 (5) | 0.1848 (3) | 0.0178 (5) | |
H4 | 0.3712 | 0.7311 | 0.2212 | 0.021* | |
C5 | 0.31386 (14) | 0.9607 (5) | 0.0978 (3) | 0.0184 (5) | |
Cl2 | 0.37258 (4) | 1.11763 (13) | 0.06163 (7) | 0.02513 (18) | |
C6 | 0.25310 (15) | 1.0223 (5) | 0.0405 (3) | 0.0211 (5) | |
H6 | 0.2433 | 1.1492 | −0.0192 | 0.025* | |
C7 | 0.20711 (15) | 0.8956 (5) | 0.0719 (3) | 0.0202 (6) | |
H7 | 0.1654 | 0.9355 | 0.0319 | 0.024* | |
N1 | 0.13248 (12) | 0.4699 (5) | 0.0939 (3) | 0.0197 (5) | |
H1 | 0.1365 | 0.4894 | 0.0063 | 0.024* | |
C8 | 0.08611 (13) | 0.3210 (5) | 0.1147 (3) | 0.0191 (5) | |
C9 | 0.10239 (14) | 0.1560 (5) | 0.2194 (3) | 0.0218 (6) | |
H9 | 0.1435 | 0.1458 | 0.2762 | 0.026* | |
C10 | 0.05858 (17) | 0.0073 (6) | 0.2407 (4) | 0.0272 (7) | |
H10 | 0.0696 | −0.1041 | 0.3123 | 0.033* | |
C11 | −0.00132 (17) | 0.0223 (6) | 0.1568 (4) | 0.0291 (7) | |
H11 | −0.0316 | −0.0780 | 0.1719 | 0.035* | |
C12 | −0.01736 (15) | 0.1832 (6) | 0.0507 (4) | 0.0261 (6) | |
H12 | −0.0584 | 0.1889 | −0.0075 | 0.031* | |
C13 | 0.02600 (14) | 0.3385 (5) | 0.0276 (3) | 0.0203 (5) | |
C14 | 0.00831 (15) | 0.5163 (6) | −0.0857 (4) | 0.0261 (6) | |
H14A | 0.0153 | 0.6622 | −0.0401 | 0.039* | |
H14B | −0.0352 | 0.5007 | −0.1358 | 0.039* | |
H14C | 0.0333 | 0.5012 | −0.1548 | 0.039* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0322 (12) | 0.0350 (13) | 0.0103 (10) | −0.0082 (9) | 0.0100 (9) | −0.0035 (8) |
C1 | 0.0219 (12) | 0.0242 (13) | 0.0107 (12) | −0.0017 (9) | 0.0067 (10) | −0.0010 (9) |
C2 | 0.0202 (11) | 0.0246 (13) | 0.0082 (10) | −0.0028 (9) | 0.0060 (9) | −0.0016 (9) |
C3 | 0.0242 (12) | 0.0183 (11) | 0.0107 (11) | −0.0014 (9) | 0.0067 (9) | −0.0010 (9) |
Cl1 | 0.0313 (4) | 0.0213 (3) | 0.0185 (3) | 0.0008 (2) | 0.0070 (3) | 0.0049 (2) |
C4 | 0.0207 (13) | 0.0207 (12) | 0.0125 (12) | −0.0008 (9) | 0.0048 (10) | 0.0008 (9) |
C5 | 0.0230 (12) | 0.0197 (11) | 0.0139 (13) | −0.0038 (9) | 0.0074 (10) | −0.0004 (9) |
Cl2 | 0.0260 (3) | 0.0289 (3) | 0.0217 (4) | −0.0064 (3) | 0.0084 (3) | 0.0042 (3) |
C6 | 0.0262 (13) | 0.0243 (13) | 0.0137 (12) | −0.0005 (10) | 0.0068 (11) | 0.0018 (10) |
C7 | 0.0225 (13) | 0.0270 (14) | 0.0115 (13) | 0.0012 (10) | 0.0053 (10) | 0.0014 (10) |
N1 | 0.0225 (11) | 0.0289 (12) | 0.0092 (10) | −0.0043 (9) | 0.0069 (9) | −0.0008 (9) |
C8 | 0.0207 (12) | 0.0266 (13) | 0.0114 (12) | −0.0019 (10) | 0.0067 (10) | −0.0032 (9) |
C9 | 0.0256 (13) | 0.0275 (14) | 0.0141 (13) | 0.0000 (11) | 0.0085 (11) | 0.0030 (11) |
C10 | 0.0376 (17) | 0.0237 (14) | 0.0233 (16) | −0.0026 (12) | 0.0134 (14) | 0.0027 (11) |
C11 | 0.0348 (17) | 0.0288 (15) | 0.0274 (18) | −0.0101 (13) | 0.0149 (14) | −0.0045 (13) |
C12 | 0.0236 (13) | 0.0322 (16) | 0.0231 (16) | −0.0039 (11) | 0.0070 (12) | −0.0050 (13) |
C13 | 0.0224 (13) | 0.0261 (13) | 0.0139 (13) | 0.0008 (10) | 0.0073 (10) | −0.0032 (10) |
C14 | 0.0252 (14) | 0.0351 (16) | 0.0181 (15) | −0.0001 (12) | 0.0060 (12) | 0.0004 (12) |
O1—C1 | 1.241 (4) | N1—H1 | 0.8800 |
C1—N1 | 1.346 (4) | C8—C9 | 1.399 (4) |
C1—C2 | 1.505 (4) | C8—C13 | 1.402 (4) |
C2—C3 | 1.396 (4) | C9—C10 | 1.388 (5) |
C2—C7 | 1.404 (4) | C9—H9 | 0.9500 |
C3—C4 | 1.397 (4) | C10—C11 | 1.386 (5) |
C3—Cl1 | 1.736 (3) | C10—H10 | 0.9500 |
C4—C5 | 1.398 (4) | C11—C12 | 1.389 (5) |
C4—H4 | 0.9500 | C11—H11 | 0.9500 |
C5—C6 | 1.388 (4) | C12—C13 | 1.412 (5) |
C5—Cl2 | 1.733 (3) | C12—H12 | 0.9500 |
C6—C7 | 1.382 (5) | C13—C14 | 1.510 (5) |
C6—H6 | 0.9500 | C14—H14A | 0.9800 |
C7—H7 | 0.9500 | C14—H14B | 0.9800 |
N1—C8 | 1.431 (4) | C14—H14C | 0.9800 |
O1—C1—N1 | 124.6 (3) | C9—C8—C13 | 121.3 (3) |
O1—C1—C2 | 120.3 (3) | C9—C8—N1 | 118.9 (3) |
N1—C1—C2 | 115.1 (3) | C13—C8—N1 | 119.7 (3) |
C3—C2—C7 | 118.4 (3) | C10—C9—C8 | 120.2 (3) |
C3—C2—C1 | 120.8 (3) | C10—C9—H9 | 119.9 |
C7—C2—C1 | 120.8 (3) | C8—C9—H9 | 119.9 |
C2—C3—C4 | 121.3 (3) | C11—C10—C9 | 119.6 (3) |
C2—C3—Cl1 | 120.0 (2) | C11—C10—H10 | 120.2 |
C4—C3—Cl1 | 118.7 (2) | C9—C10—H10 | 120.2 |
C3—C4—C5 | 118.2 (3) | C10—C11—C12 | 120.3 (3) |
C3—C4—H4 | 120.9 | C10—C11—H11 | 119.8 |
C5—C4—H4 | 120.9 | C12—C11—H11 | 119.8 |
C6—C5—C4 | 121.8 (3) | C11—C12—C13 | 121.4 (3) |
C6—C5—Cl2 | 119.9 (2) | C11—C12—H12 | 119.3 |
C4—C5—Cl2 | 118.3 (2) | C13—C12—H12 | 119.3 |
C7—C6—C5 | 118.8 (3) | C8—C13—C12 | 117.1 (3) |
C7—C6—H6 | 120.6 | C8—C13—C14 | 121.5 (3) |
C5—C6—H6 | 120.6 | C12—C13—C14 | 121.4 (3) |
C6—C7—C2 | 121.5 (3) | C13—C14—H14A | 109.5 |
C6—C7—H7 | 119.3 | C13—C14—H14B | 109.5 |
C2—C7—H7 | 119.3 | H14A—C14—H14B | 109.5 |
C1—N1—C8 | 123.1 (3) | C13—C14—H14C | 109.5 |
C1—N1—H1 | 118.5 | H14A—C14—H14C | 109.5 |
C8—N1—H1 | 118.5 | H14B—C14—H14C | 109.5 |
O1—C1—C2—C3 | 66.1 (4) | C1—C2—C7—C6 | 176.2 (3) |
N1—C1—C2—C3 | −114.1 (3) | O1—C1—N1—C8 | −7.1 (5) |
O1—C1—C2—C7 | −111.4 (4) | C2—C1—N1—C8 | 173.2 (3) |
N1—C1—C2—C7 | 68.4 (4) | C1—N1—C8—C9 | −50.9 (4) |
C7—C2—C3—C4 | 0.3 (4) | C1—N1—C8—C13 | 130.9 (3) |
C1—C2—C3—C4 | −177.3 (3) | C13—C8—C9—C10 | −1.0 (5) |
C7—C2—C3—Cl1 | −179.2 (2) | N1—C8—C9—C10 | −179.1 (3) |
C1—C2—C3—Cl1 | 3.2 (4) | C8—C9—C10—C11 | 0.4 (5) |
C2—C3—C4—C5 | 1.2 (4) | C9—C10—C11—C12 | 0.8 (6) |
Cl1—C3—C4—C5 | −179.3 (2) | C10—C11—C12—C13 | −1.6 (6) |
C3—C4—C5—C6 | −1.7 (5) | C9—C8—C13—C12 | 0.3 (5) |
C3—C4—C5—Cl2 | 178.4 (2) | N1—C8—C13—C12 | 178.4 (3) |
C4—C5—C6—C7 | 0.6 (5) | C9—C8—C13—C14 | −180.0 (3) |
Cl2—C5—C6—C7 | −179.4 (2) | N1—C8—C13—C14 | −1.8 (4) |
C5—C6—C7—C2 | 1.0 (5) | C11—C12—C13—C8 | 1.0 (5) |
C3—C2—C7—C6 | −1.4 (5) | C11—C12—C13—C14 | −178.8 (3) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1i | 0.88 | 2.04 | 2.865 (4) | 156 |
C6—H6···O1ii | 0.95 | 2.55 | 3.415 (4) | 151 |
C11—H11···Cl2iii | 0.95 | 2.83 | 3.680 (3) | 150 |
C14—H14C···Cg2i | 0.98 | 2.87 | 3.528 (4) | 125 |
Symmetry codes: (i) x, −y+1, z−1/2; (ii) x, −y+2, z−1/2; (iii) x−1/2, y−3/2, z. |
Experimental details
Crystal data | |
Chemical formula | C14H11Cl2NO |
Mr | 280.14 |
Crystal system, space group | Monoclinic, Cc |
Temperature (K) | 92 |
a, b, c (Å) | 22.517 (4), 6.0405 (9), 9.6332 (17) |
β (°) | 104.838 (9) |
V (Å3) | 1266.6 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.50 |
Crystal size (mm) | 0.46 × 0.27 × 0.19 |
Data collection | |
Diffractometer | Bruker APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2006) |
Tmin, Tmax | 0.615, 0.91 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 9889, 3475, 3195 |
Rint | 0.043 |
(sin θ/λ)max (Å−1) | 0.768 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.057, 0.158, 1.15 |
No. of reflections | 3475 |
No. of parameters | 164 |
No. of restraints | 2 |
H-atom treatment | H-atom parameters constrained |
Δρmax, Δρmin (e Å−3) | 1.36, −0.62 |
Absolute structure | Flack (1983), 1248 Friedel pairs |
Absolute structure parameter | 0.05 (8) |
Computer programs: APEX2 (Bruker, 2006), APEX2 and SAINT (Bruker, 2006), SAINT (Bruker, 2006), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008) and TITAN (Hunter & Simpson, 1999), SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006), SHELXL97 (Sheldrick, 2008), enCIFer (Allen et al., 2004), PLATON (Spek, 2009) and publCIF (Westrip, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O1i | 0.88 | 2.04 | 2.865 (4) | 156 |
C6—H6···O1ii | 0.95 | 2.55 | 3.415 (4) | 151 |
C11—H11···Cl2iii | 0.95 | 2.83 | 3.680 (3) | 150 |
C14—H14C···Cg2i | 0.98 | 2.87 | 3.528 (4) | 125 |
Symmetry codes: (i) x, −y+1, z−1/2; (ii) x, −y+2, z−1/2; (iii) x−1/2, y−3/2, z. |
Acknowledgements
We thank the University of Otago for purchase of the diffractometer.
References
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The biological activity and applications of benzamide derivatives have been described in an earlier paper (Saeed et al. 2008a). In the title compound, (I) & Fig. 1, the central C2–C1(O1)–N1–C8 amide unit makes dihedral angles of 68.71 (11) ° and 54.92 (12) ° with the C2···C7 and C8···C13 rings, respectively. The two aromatic rings are inclined at 16.25 (17)°. Bond distances within the molecule are normal (Allen et al. 1987) and similar to those observed in comparable structures (Gowda et al. 2008; Saeed et al. 2008b; Zhou & Zheng 2007). In the crystal, N1—H1···O1 hydrogen bonds link molecules into zig-zag chains down the c axis; Table 1 & Fig. 2. C11—H11···Cl2 contacts link these chains and additional C6—H6···O1 contacts generate three-dimensional stacks down b, Fig. 3. C14—H14···π and Cl1···π interactions (Cl···Cg1 distance 3.5422 (15) Å; Cg1 is the centroid of the C2···C7 ring) may also stabilize the structure.