organic compounds
2,4-Dichloro-N-p-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 C—N—C(=O)—C amide unit is almost planar (r.m.s. deviation = 0.0317 Å) and subtends dihedral angles of 65.93 (6) and 29.45 (7)°, respectively, to the dichlorobenzene and tolyl rings. The two aromatic rings are inclined at 37.92 (6)° to one another. In the N—H⋯O hydrogen bonds link the molecules into chains along b. Additional weak C—H⋯Cl and C—H⋯O hydrogen bonds combine with C—H⋯π and very weak π–π contacts [Cg⋯Cg distance = 4.0217 (12) Å] to stack the molecules down b.
Related literature
For background to our work on benzamide derivatives, see: Saeed et al. (2008). For related structures see: Zhou & Zheng (2007); Gowda et al. (2008a,b,c, 2009); Chopra & Guru Row (2005).
Experimental
Crystal data
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Refinement
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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/S1600536809034710/fl2252sup1.cif
contains datablocks global, I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536809034710/fl2252Isup2.hkl
2,4-Dichlorobenzoyl chloride (5.4 mmol) in CHCl3 was treated with p-toluidine(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 magnesium sulfate and concentrated under reduced pressure. Crystallization of the residue by evaporation from CHCl3 afforded the title compound (84%) as colourless needles: Anal. calcd. for C14H11Cl2NO,: C, 60.02; H, 3.96; N, 5.00%; found: C, 60.06; H, 3.92; N, 5.10%
The H atom bound to N1 was located in a difference Fourier map and its coordinates were refined with Uiso=1.2Ueq (N). All other H-atoms were placed in calculated positions and refined using a riding model with d(C—H) = 0.95 Å, Uiso=1.2Ueq (C) for aromatic and 0.98 Å, Uiso = 1.5Ueq (C) for CH3 H 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 TITAN2000 (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 = 1.475 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 5859 reflections |
a = 9.0884 (18) Å | θ = 2.5–33.0° |
b = 9.825 (2) Å | µ = 0.50 mm−1 |
c = 14.167 (3) Å | T = 89 K |
β = 94.208 (9)° | Irregular fragment, colourless |
V = 1261.6 (4) Å3 | 0.33 × 0.26 × 0.06 mm |
Z = 4 |
Bruker APEXII CCD diffractometer | 4465 independent reflections |
Radiation source: fine-focus sealed tube | 3463 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.044 |
ω scans | θmax = 33.1°, θmin = 2.9° |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | h = −13→13 |
Tmin = 0.753, Tmax = 0.970 | k = −14→13 |
20982 measured reflections | l = −21→21 |
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)] = 0.041 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.132 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.15 | w = 1/[σ2(Fo2) + (0.0688P)2 + 0.2064P] where P = (Fo2 + 2Fc2)/3 |
4465 reflections | (Δ/σ)max = 0.001 |
167 parameters | Δρmax = 0.57 e Å−3 |
0 restraints | Δρmin = −0.49 e Å−3 |
C14H11Cl2NO | V = 1261.6 (4) Å3 |
Mr = 280.14 | Z = 4 |
Monoclinic, P21/c | Mo Kα radiation |
a = 9.0884 (18) Å | µ = 0.50 mm−1 |
b = 9.825 (2) Å | T = 89 K |
c = 14.167 (3) Å | 0.33 × 0.26 × 0.06 mm |
β = 94.208 (9)° |
Bruker APEXII CCD diffractometer | 4465 independent reflections |
Absorption correction: multi-scan (SADABS; Bruker, 2006) | 3463 reflections with I > 2σ(I) |
Tmin = 0.753, Tmax = 0.970 | Rint = 0.044 |
20982 measured reflections |
R[F2 > 2σ(F2)] = 0.041 | 0 restraints |
wR(F2) = 0.132 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.15 | Δρmax = 0.57 e Å−3 |
4465 reflections | Δρmin = −0.49 e Å−3 |
167 parameters |
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 | ||
C1 | 0.52742 (16) | 0.71474 (14) | 0.71812 (10) | 0.0111 (3) | |
C2 | 0.43510 (16) | 0.67111 (13) | 0.63071 (10) | 0.0105 (3) | |
C3 | 0.29263 (16) | 0.61878 (14) | 0.63334 (10) | 0.0121 (3) | |
C4 | 0.21096 (16) | 0.57806 (14) | 0.55106 (10) | 0.0126 (3) | |
H4 | 0.1147 | 0.5414 | 0.5539 | 0.015* | |
C5 | 0.27317 (16) | 0.59219 (14) | 0.46479 (10) | 0.0125 (3) | |
C6 | 0.41328 (16) | 0.64737 (14) | 0.45883 (10) | 0.0130 (3) | |
H6 | 0.4536 | 0.6584 | 0.3993 | 0.016* | |
C7 | 0.49281 (16) | 0.68595 (14) | 0.54224 (11) | 0.0125 (3) | |
H7 | 0.5887 | 0.7233 | 0.5391 | 0.015* | |
C8 | 0.66786 (16) | 0.62192 (14) | 0.86070 (10) | 0.0109 (3) | |
C9 | 0.77909 (17) | 0.71922 (15) | 0.87165 (11) | 0.0141 (3) | |
H9 | 0.7902 | 0.7855 | 0.8239 | 0.017* | |
C10 | 0.87396 (17) | 0.71820 (15) | 0.95361 (11) | 0.0153 (3) | |
H10 | 0.9498 | 0.7847 | 0.9607 | 0.018* | |
C11 | 0.86130 (16) | 0.62256 (14) | 1.02572 (11) | 0.0131 (3) | |
C12 | 0.74965 (17) | 0.52520 (15) | 1.01274 (11) | 0.0142 (3) | |
H12 | 0.7388 | 0.4585 | 1.0603 | 0.017* | |
C13 | 0.65393 (16) | 0.52412 (14) | 0.93137 (10) | 0.0123 (3) | |
H13 | 0.5789 | 0.4568 | 0.9238 | 0.015* | |
C14 | 0.96308 (18) | 0.62590 (17) | 1.11523 (11) | 0.0184 (3) | |
H14A | 0.9120 | 0.6683 | 1.1662 | 0.028* | |
H14B | 1.0515 | 0.6788 | 1.1040 | 0.028* | |
H14C | 0.9916 | 0.5328 | 1.1334 | 0.028* | |
N1 | 0.56897 (14) | 0.61267 (12) | 0.77821 (9) | 0.0120 (2) | |
O1 | 0.56444 (13) | 0.83472 (10) | 0.72985 (8) | 0.0168 (2) | |
Cl1 | 0.20933 (4) | 0.60815 (4) | 0.73967 (3) | 0.01815 (11) | |
Cl2 | 0.17246 (4) | 0.53821 (4) | 0.36221 (3) | 0.01910 (11) | |
H1N | 0.530 (2) | 0.534 (2) | 0.7672 (16) | 0.023* |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.0116 (6) | 0.0104 (6) | 0.0112 (6) | 0.0005 (5) | 0.0004 (5) | 0.0007 (5) |
C2 | 0.0122 (6) | 0.0073 (6) | 0.0117 (6) | 0.0008 (4) | −0.0010 (5) | 0.0009 (4) |
C3 | 0.0135 (6) | 0.0120 (6) | 0.0107 (6) | 0.0020 (5) | 0.0011 (5) | 0.0023 (5) |
C4 | 0.0108 (6) | 0.0127 (6) | 0.0141 (7) | −0.0008 (5) | −0.0005 (5) | 0.0009 (5) |
C5 | 0.0145 (6) | 0.0111 (6) | 0.0115 (6) | 0.0015 (5) | −0.0020 (5) | −0.0012 (5) |
C6 | 0.0154 (6) | 0.0114 (6) | 0.0123 (6) | 0.0003 (5) | 0.0022 (5) | 0.0005 (5) |
C7 | 0.0127 (6) | 0.0095 (6) | 0.0153 (7) | −0.0011 (5) | 0.0005 (5) | 0.0005 (5) |
C8 | 0.0121 (6) | 0.0091 (6) | 0.0112 (6) | 0.0016 (4) | −0.0006 (5) | −0.0013 (4) |
C9 | 0.0154 (6) | 0.0127 (6) | 0.0137 (6) | −0.0026 (5) | −0.0014 (5) | 0.0035 (5) |
C10 | 0.0141 (7) | 0.0134 (6) | 0.0179 (7) | −0.0031 (5) | −0.0015 (6) | 0.0003 (5) |
C11 | 0.0117 (6) | 0.0141 (6) | 0.0133 (6) | 0.0011 (5) | −0.0008 (5) | −0.0002 (5) |
C12 | 0.0166 (7) | 0.0131 (6) | 0.0125 (6) | −0.0014 (5) | −0.0008 (5) | 0.0026 (5) |
C13 | 0.0130 (6) | 0.0103 (6) | 0.0134 (6) | −0.0019 (5) | −0.0001 (5) | 0.0005 (5) |
C14 | 0.0182 (7) | 0.0217 (7) | 0.0145 (7) | −0.0031 (6) | −0.0037 (6) | 0.0012 (6) |
N1 | 0.0154 (6) | 0.0084 (5) | 0.0115 (6) | −0.0014 (4) | −0.0034 (5) | 0.0006 (4) |
O1 | 0.0210 (6) | 0.0084 (5) | 0.0199 (5) | −0.0009 (4) | −0.0056 (4) | 0.0009 (4) |
Cl1 | 0.01473 (18) | 0.0284 (2) | 0.01157 (18) | 0.00040 (13) | 0.00261 (13) | 0.00371 (13) |
Cl2 | 0.01772 (19) | 0.0254 (2) | 0.01362 (18) | −0.00149 (13) | −0.00263 (14) | −0.00494 (13) |
C1—O1 | 1.2338 (17) | C8—C13 | 1.400 (2) |
C1—N1 | 1.3512 (18) | C8—N1 | 1.4240 (18) |
C1—C2 | 1.5062 (19) | C9—C10 | 1.395 (2) |
C2—C3 | 1.396 (2) | C9—H9 | 0.9500 |
C2—C7 | 1.401 (2) | C10—C11 | 1.399 (2) |
C3—C4 | 1.394 (2) | C10—H10 | 0.9500 |
C3—Cl1 | 1.7379 (16) | C11—C12 | 1.397 (2) |
C4—C5 | 1.391 (2) | C11—C14 | 1.514 (2) |
C4—H4 | 0.9500 | C12—C13 | 1.392 (2) |
C5—C6 | 1.392 (2) | C12—H12 | 0.9500 |
C5—Cl2 | 1.7423 (15) | C13—H13 | 0.9500 |
C6—C7 | 1.392 (2) | C14—H14A | 0.9800 |
C6—H6 | 0.9500 | C14—H14B | 0.9800 |
C7—H7 | 0.9500 | C14—H14C | 0.9800 |
C8—C9 | 1.392 (2) | N1—H1N | 0.86 (2) |
O1—C1—N1 | 124.29 (13) | C8—C9—C10 | 119.17 (13) |
O1—C1—C2 | 120.84 (12) | C8—C9—H9 | 120.4 |
N1—C1—C2 | 114.82 (12) | C10—C9—H9 | 120.4 |
C3—C2—C7 | 118.10 (13) | C9—C10—C11 | 122.27 (14) |
C3—C2—C1 | 122.99 (13) | C9—C10—H10 | 118.9 |
C7—C2—C1 | 118.90 (13) | C11—C10—H10 | 118.9 |
C4—C3—C2 | 121.42 (14) | C12—C11—C10 | 117.50 (13) |
C4—C3—Cl1 | 117.94 (12) | C12—C11—C14 | 121.22 (14) |
C2—C3—Cl1 | 120.61 (11) | C10—C11—C14 | 121.27 (13) |
C5—C4—C3 | 118.71 (14) | C13—C12—C11 | 121.19 (14) |
C5—C4—H4 | 120.6 | C13—C12—H12 | 119.4 |
C3—C4—H4 | 120.6 | C11—C12—H12 | 119.4 |
C4—C5—C6 | 121.66 (13) | C12—C13—C8 | 120.20 (13) |
C4—C5—Cl2 | 118.69 (11) | C12—C13—H13 | 119.9 |
C6—C5—Cl2 | 119.65 (12) | C8—C13—H13 | 119.9 |
C7—C6—C5 | 118.36 (14) | C11—C14—H14A | 109.5 |
C7—C6—H6 | 120.8 | C11—C14—H14B | 109.5 |
C5—C6—H6 | 120.8 | H14A—C14—H14B | 109.5 |
C6—C7—C2 | 121.72 (13) | C11—C14—H14C | 109.5 |
C6—C7—H7 | 119.1 | H14A—C14—H14C | 109.5 |
C2—C7—H7 | 119.1 | H14B—C14—H14C | 109.5 |
C9—C8—C13 | 119.66 (13) | C1—N1—C8 | 126.87 (12) |
C9—C8—N1 | 123.01 (13) | C1—N1—H1N | 117.5 (14) |
C13—C8—N1 | 117.28 (12) | C8—N1—H1N | 115.6 (14) |
O1—C1—C2—C3 | −115.79 (17) | C1—C2—C7—C6 | 179.87 (12) |
N1—C1—C2—C3 | 66.64 (18) | C13—C8—C9—C10 | −0.6 (2) |
O1—C1—C2—C7 | 62.85 (19) | N1—C8—C9—C10 | −178.01 (14) |
N1—C1—C2—C7 | −114.72 (15) | C8—C9—C10—C11 | −0.1 (2) |
C7—C2—C3—C4 | 2.0 (2) | C9—C10—C11—C12 | 0.6 (2) |
C1—C2—C3—C4 | −179.31 (13) | C9—C10—C11—C14 | −178.33 (15) |
C7—C2—C3—Cl1 | −175.69 (10) | C10—C11—C12—C13 | −0.5 (2) |
C1—C2—C3—Cl1 | 2.96 (19) | C14—C11—C12—C13 | 178.50 (14) |
C2—C3—C4—C5 | −0.9 (2) | C11—C12—C13—C8 | −0.2 (2) |
Cl1—C3—C4—C5 | 176.86 (11) | C9—C8—C13—C12 | 0.8 (2) |
C3—C4—C5—C6 | −0.9 (2) | N1—C8—C13—C12 | 178.32 (13) |
C3—C4—C5—Cl2 | 178.77 (11) | O1—C1—N1—C8 | −4.3 (2) |
C4—C5—C6—C7 | 1.5 (2) | C2—C1—N1—C8 | 173.21 (13) |
Cl2—C5—C6—C7 | −178.17 (11) | C9—C8—N1—C1 | −26.7 (2) |
C5—C6—C7—C2 | −0.3 (2) | C13—C8—N1—C1 | 155.92 (15) |
C3—C2—C7—C6 | −1.4 (2) |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O1i | 0.86 (2) | 2.14 (2) | 2.9867 (17) | 168 (2) |
C12—H12···Cl1ii | 0.95 | 2.91 | 3.7372 (17) | 146 |
C6—H6···O1iii | 0.95 | 2.67 | 3.619 (2) | 175 |
C7—H7···Cg2iv | 0.95 | 2.65 | 3.4865 (17) | 147 |
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) −x+1, −y+1, −z+2; (iii) x, −y+3/2, z−1/2; (iv) x, −y+3/2, z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C14H11Cl2NO |
Mr | 280.14 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 89 |
a, b, c (Å) | 9.0884 (18), 9.825 (2), 14.167 (3) |
β (°) | 94.208 (9) |
V (Å3) | 1261.6 (4) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.50 |
Crystal size (mm) | 0.33 × 0.26 × 0.06 |
Data collection | |
Diffractometer | Bruker APEXII CCD diffractometer |
Absorption correction | Multi-scan (SADABS; Bruker, 2006) |
Tmin, Tmax | 0.753, 0.970 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 20982, 4465, 3463 |
Rint | 0.044 |
(sin θ/λ)max (Å−1) | 0.769 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.041, 0.132, 1.15 |
No. of reflections | 4465 |
No. of parameters | 167 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.57, −0.49 |
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., 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—H1N···O1i | 0.86 (2) | 2.14 (2) | 2.9867 (17) | 168 (2) |
C12—H12···Cl1ii | 0.95 | 2.91 | 3.7372 (17) | 145.8 |
C6—H6···O1iii | 0.95 | 2.67 | 3.619 (2) | 174.8 |
C7—H7···Cg2iv | 0.95 | 2.65 | 3.4865 (17) | 147 |
Symmetry codes: (i) −x+1, y−1/2, −z+3/2; (ii) −x+1, −y+1, −z+2; (iii) x, −y+3/2, z−1/2; (iv) x, −y+3/2, z+1/2. |
Acknowledgements
We thank the University of Otago for purchase of the diffractometer.
References
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The background to our work on benzamide derivatives has been described in a previous paper (Saeed et al., 2008). In the title compound (I), Fig. 1, the C8–N1–C1(O1)–C2 amide unit is planar, r.m.s. deviation 0.0317 Å, and subtends dihedral angles of 65.93 (6)° and 29.45 (7)° respectively to the C2···C7 dichlorobenzene and C8···C13 tolyl rings. The two aromatic rings are inclined at 37.92 (6)° to one another. Bond distances within the molecule are normal and similar to those observed in comparable structures (Zhou & Zheng, 2007; Gowda et al. 2008a,b,c 2009; Chopra & Guru Row, 2005).
In the crystal structure N—H···O hydrogen bonds link molecules in a head to tail fashion into rows along b. C7—H7···π and weak, inversion related π–π contacts involving adjacent dichlorobenene rings [Cg···Cg distance 4.0217 (12), symmetry operation 1 - x, 1 - y, 1 - z] are also observed, Table 1, Fig 2. These together with additional C—H···Cl and C—H···O hydrogen bonds link the stacks of molecules alternately head to head and head to tail down the b axis, Fig. 3.