organic compounds
N-(2-Chlorophenyl)-N′-(2-methylphenyl)succinamide
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
In the title compound, C17H17ClN2O2, the contains half a molecule with a centre of symmetry at the mid-point of the central C—C bond. The conformations of the amide O atoms are anti to the methylene atoms. Further, the N—H bonds in the amide fragments are anti to the ortho-chloro/methyl groups in the adjacent benzene rings. The dihedral angle between the benzene ring and the NH—C(O)—CH2 segment in the two halves of the molecule is 62.0 (2)°. In the crystal, a series of N—H⋯O intermolecular hydrogen bonds link the molecules into column-like infinite chains along the a axis. The methyl and Cl groups are disordered with respect to the ortho positions of the benzene ring, with site-occupation factors of 0.5 each.
Related literature
For our studies on the effects of substituents on the structures of N-(aryl)-amides, see: Bhat & Gowda (2000); Gowda et al. (2007a); Saraswathi et al. (2011a,b,c); and on the structures of N-(aryl)-methanesulfonamides, see: Gowda et al. (2007b). For similar structures, see: Pierrot et al. (1984). For restrained geometry, see: Nardelli (1999).
Experimental
Crystal data
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Refinement
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Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97.
Supporting information
https://doi.org/10.1107/S1600536811035616/vm2112sup1.cif
contains datablocks I, global. DOI:Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536811035616/vm2112Isup2.hkl
Supporting information file. DOI: https://doi.org/10.1107/S1600536811035616/vm2112Isup3.cml
Succinic anhydride (0.01 mol) in toluene (25 ml) was treated drop wise with 2-chloroaniline (0.01 mol) also in toluene (20 ml) with constant stirring. The resulting mixture was stirred for one hour and set aside for an additional hour at room temperature for completion of the reaction. The mixture was then treated with dilute hydrochloric acid to remove unreacted 2-chloroaniline. The resultant solid N-(2-chlorophenyl)-succinamic acid was filtered under suction and washed thoroughly with water to remove the unreacted succinic anhydride and succinic acid. The compound was recrystallized to constant melting point from ethanol. The purity of the compound was checked by elemental analysis and characterized by its infrared and NMR spectra.
The N-(2-chlorophenyl)succinamic acid obtained was then treated with phosphorous oxychloride and excess of 2-methylaniline at room temperature with constant stirring. The resultant mixture was stirred for 4 h, kept aside for additional 6 h for completion of the reaction and poured slowly into crushed ice with constant stirring. It was kept aside for a day. The resultant solid, N-(2-chlorophenyl), N-(2-methylphenyl)-succinamide was filtered under suction, washed thoroughly with water, dilute sodium hydroxide solution and finally with water. It was recrystallized to constant melting point from a mixture of acetone and toluene (3:1 v/v). The compound was characterized by its infrared and NMR spectra.
Needle like colorless single crystals used in X-ray diffraction studies were grown in a mixture of acetone and toluene (3:1 v/v) at room temperature.
The H atom of the NH group was located in a difference map and later restrained to the distance N—H = 0.86 (2) Å. The other H atoms were positioned with idealized geometry using a riding model with the aromatic C—H = 0.93 Å, methyl C—H = 0.97 Å, and the methylene C—H = 0.97 Å.
All H atoms were refined with isotropic displacement parameters. The Uiso(H) values were set at 1.2Ueq(C-aromatic, N) and 1.5Ueq(C-methyl).
The residual electron-density features are located in the region of Cl1 and C2. The highest peak is 0.66 Å from Cl1 and the deepest hole is 0.23 Å from C2.
C9 and Cl1 are disordered and were refined using a split model. The corresponding site-occupation factors were fixed to 0.50:0.50. The Uij components of C9 were restrained to approximate isotropic behavoir (Nardelli, 1999). The bond lengths C2–C9 and C2–Cl1 were restrained to 1.54 (1) and 1.74 (1) Å, respectively.
The amide and sulfonamide moieties are important constituents of many biologically significant compounds. As part of our studies on the substituent effects on the structures of this class of compounds (Bhat & Gowda, 2000; Gowda et al., 2007a,b; Saraswathi et al., 2011a,b,c), in the present work, the structure of N-(2-Chlorophenyl),N-(2-methylphenyl)-succinamide (I) has been determined (Fig.1). The
of (I) contains half a molecule with a center of symmetry at the mid-point of the central C—C bond, similar to that obseved in bis(2-chlorophenylaminocarbonylmethyl)disulfide (II) (Pierrot et al., 1984), N-(3-Chlorophenyl),N-(3-methylphenyl)- succinamide (III) (Saraswathi et al., 2011c), N,N-bis(2-chlorophenyl)-succinamide (IV) (Saraswathi et al., 2011b) and N,N-bis(2-methylphenyl)-succinamide dihydrate (V) (Saraswathi et al., 2011a).The conformations of the amide O atoms are anti to the H atoms attached to the adjacent C atoms. Further, the conformations of the N—H bonds in the amide fragments are anti to the ortho- chloro/methyl groups in the adjacent benzene rings, similar to that observed with respect to the meta-chloro/methyl groups in (III), and the anti conformations observed with respect to the ortho-methyl groups in (V), but contrary to the syn conformations observed between the N—H bonds in the amide fragments and the ortho-chloro groups in the adjacent benzene rings of (IV).
Further, C1—N1—C7—C8 and C1a—N1a—C7a—C8a segments in (I) are nearly linear, similar to those observed in (III), (IV) and (V). The torsion angles of C2—C1—N1—C7 and C6—C1—N1—C7 are -64.3 (8)° and 115.8 (6)°, compared to the values of -43.2 (4)° and 138.6 (3)° in (III), -47.6 (6)° and 133.7 (4)° in (IV) and -64.0 (4)° and 117.6 (3)° in (V).
The dihedral angle between the benzene ring and the NH—C(O)—CH2 segment in the two halves of the molecule is 62.0 (2)°, compared to the values of 43.5 (1)° in (III), 47.0 (2)° in (IV) and 62.1 (2)° in (V).
The packing of molecules in the crystal linked by of N—H···O hydrogen bonds (Table 1) is shown in Fig. 2.
For our studies on the effects of substituents on the structures of N-(aryl)-amides, see: Bhat & Gowda (2000); Gowda et al. (2007a); Saraswathi et al. (2011a,b,c); and on the structures of N-(aryl)-methanesulfonamides, see: Gowda et al. (2007b). For similar structures, see: Pierrot et al. (1984). For restrained geometry, see: Nardelli (1999).
Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell
CrysAlis RED (Oxford Diffraction, 2009); data reduction: CrysAlis RED (Oxford Diffraction, 2009); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).C17H17ClN2O2 | F(000) = 332 |
Mr = 316.78 | Dx = 1.342 Mg m−3 |
Monoclinic, P21/c | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: -P 2ybc | Cell parameters from 611 reflections |
a = 11.541 (3) Å | θ = 2.6–27.9° |
b = 7.908 (2) Å | µ = 0.25 mm−1 |
c = 8.798 (2) Å | T = 293 K |
β = 102.55 (2)° | Needle, colourless |
V = 783.8 (3) Å3 | 0.48 × 0.04 × 0.04 mm |
Z = 2 |
Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector | 1391 independent reflections |
Radiation source: fine-focus sealed tube | 824 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.044 |
Rotation method data acquisition using ω scans | θmax = 25.2°, θmin = 3.2° |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009) | h = −9→13 |
Tmin = 0.889, Tmax = 0.990 | k = −9→5 |
2598 measured reflections | l = −9→10 |
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)] = 0.105 | Hydrogen site location: inferred from neighbouring sites |
wR(F2) = 0.164 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.28 | w = 1/[σ2(Fo2) + (0.0062P)2 + 2.1127P] where P = (Fo2 + 2Fc2)/3 |
1391 reflections | (Δ/σ)max < 0.001 |
112 parameters | Δρmax = 0.26 e Å−3 |
9 restraints | Δρmin = −0.31 e Å−3 |
C17H17ClN2O2 | V = 783.8 (3) Å3 |
Mr = 316.78 | Z = 2 |
Monoclinic, P21/c | Mo Kα radiation |
a = 11.541 (3) Å | µ = 0.25 mm−1 |
b = 7.908 (2) Å | T = 293 K |
c = 8.798 (2) Å | 0.48 × 0.04 × 0.04 mm |
β = 102.55 (2)° |
Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector | 1391 independent reflections |
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009) | 824 reflections with I > 2σ(I) |
Tmin = 0.889, Tmax = 0.990 | Rint = 0.044 |
2598 measured reflections |
R[F2 > 2σ(F2)] = 0.105 | 9 restraints |
wR(F2) = 0.164 | H atoms treated by a mixture of independent and constrained refinement |
S = 1.28 | Δρmax = 0.26 e Å−3 |
1391 reflections | Δρmin = −0.31 e Å−3 |
112 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 | Occ. (<1) | |
C1 | 0.2685 (5) | 0.4153 (7) | 0.0447 (6) | 0.0318 (14) | |
C2 | 0.1709 (5) | 0.3763 (7) | 0.1055 (6) | 0.0370 (15) | |
C3 | 0.1179 (6) | 0.5036 (9) | 0.1745 (7) | 0.0526 (18) | |
H3 | 0.0527 | 0.4781 | 0.2165 | 0.063* | |
C4 | 0.1595 (6) | 0.6660 (9) | 0.1821 (8) | 0.0579 (19) | |
H4 | 0.1227 | 0.7495 | 0.2293 | 0.069* | |
C5 | 0.2556 (6) | 0.7058 (8) | 0.1202 (8) | 0.0557 (19) | |
H5 | 0.2839 | 0.8163 | 0.1248 | 0.067* | |
C6 | 0.3099 (6) | 0.5805 (8) | 0.0512 (7) | 0.0489 (18) | |
H6 | 0.3747 | 0.6071 | 0.0087 | 0.059* | |
C7 | 0.3869 (5) | 0.1569 (7) | 0.0508 (6) | 0.0303 (13) | |
C8 | 0.4477 (5) | 0.0460 (7) | −0.0481 (6) | 0.0353 (14) | |
H8A | 0.3913 | −0.0357 | −0.1034 | 0.042* | |
H8B | 0.4743 | 0.1154 | −0.1249 | 0.042* | |
C9 | 0.110 (3) | 0.203 (3) | 0.095 (5) | 0.057 (12) | 0.50 |
H9A | 0.1531 | 0.1238 | 0.0459 | 0.068* | 0.50 |
H9B | 0.0301 | 0.2127 | 0.0350 | 0.068* | 0.50 |
H9C | 0.1083 | 0.1639 | 0.1980 | 0.068* | 0.50 |
N1 | 0.3288 (4) | 0.2897 (6) | −0.0256 (5) | 0.0346 (12) | |
H1N | 0.338 (4) | 0.316 (7) | −0.116 (3) | 0.041* | |
O1 | 0.3888 (3) | 0.1237 (5) | 0.1871 (4) | 0.0410 (11) | |
Cl1 | 0.1161 (9) | 0.1725 (10) | 0.0927 (15) | 0.057 (2) | 0.50 |
U11 | U22 | U33 | U12 | U13 | U23 | |
C1 | 0.038 (3) | 0.033 (3) | 0.026 (3) | 0.007 (3) | 0.011 (3) | 0.005 (3) |
C2 | 0.039 (4) | 0.037 (4) | 0.037 (4) | 0.006 (3) | 0.012 (3) | 0.002 (3) |
C3 | 0.052 (4) | 0.062 (5) | 0.050 (4) | 0.021 (4) | 0.025 (3) | 0.002 (4) |
C4 | 0.070 (5) | 0.046 (5) | 0.061 (5) | 0.027 (4) | 0.021 (4) | −0.005 (4) |
C5 | 0.075 (5) | 0.028 (4) | 0.065 (5) | 0.009 (4) | 0.018 (4) | 0.003 (3) |
C6 | 0.063 (5) | 0.038 (4) | 0.052 (4) | 0.003 (3) | 0.027 (4) | 0.011 (3) |
C7 | 0.039 (3) | 0.029 (3) | 0.024 (3) | 0.000 (3) | 0.009 (3) | −0.002 (3) |
C8 | 0.044 (4) | 0.039 (3) | 0.026 (3) | 0.010 (3) | 0.013 (3) | −0.006 (3) |
C9 | 0.063 (15) | 0.051 (13) | 0.057 (14) | 0.014 (8) | 0.016 (9) | −0.003 (8) |
N1 | 0.048 (3) | 0.037 (3) | 0.025 (3) | 0.010 (2) | 0.023 (2) | 0.004 (2) |
O1 | 0.065 (3) | 0.041 (2) | 0.023 (2) | 0.017 (2) | 0.021 (2) | 0.0045 (19) |
Cl1 | 0.046 (3) | 0.051 (3) | 0.084 (5) | −0.010 (3) | 0.031 (3) | −0.008 (3) |
C1—C2 | 1.383 (7) | C6—H6 | 0.9300 |
C1—C6 | 1.388 (7) | C7—O1 | 1.223 (6) |
C1—N1 | 1.429 (6) | C7—N1 | 1.345 (7) |
C2—C3 | 1.384 (7) | C7—C8 | 1.512 (7) |
C2—C9 | 1.535 (10) | C8—C8i | 1.503 (10) |
C2—Cl1 | 1.725 (7) | C8—H8A | 0.9700 |
C3—C4 | 1.367 (9) | C8—H8B | 0.9700 |
C3—H3 | 0.9300 | C9—H9A | 0.9600 |
C4—C5 | 1.375 (8) | C9—H9B | 0.9600 |
C4—H4 | 0.9300 | C9—H9C | 0.9600 |
C5—C6 | 1.382 (8) | N1—H1N | 0.853 (19) |
C5—H5 | 0.9300 | ||
C2—C1—C6 | 119.7 (5) | C1—C6—H6 | 119.7 |
C2—C1—N1 | 121.8 (5) | O1—C7—N1 | 124.0 (5) |
C6—C1—N1 | 118.5 (5) | O1—C7—C8 | 121.9 (5) |
C1—C2—C3 | 118.8 (5) | N1—C7—C8 | 114.1 (4) |
C1—C2—C9 | 125.3 (16) | C8i—C8—C7 | 111.9 (5) |
C3—C2—C9 | 115.8 (15) | C8i—C8—H8A | 109.2 |
C1—C2—Cl1 | 120.0 (5) | C7—C8—H8A | 109.2 |
C3—C2—Cl1 | 121.2 (6) | C8i—C8—H8B | 109.2 |
C9—C2—Cl1 | 5.9 (18) | C7—C8—H8B | 109.2 |
C4—C3—C2 | 121.4 (6) | H8A—C8—H8B | 107.9 |
C4—C3—H3 | 119.3 | C2—C9—H9A | 109.5 |
C2—C3—H3 | 119.3 | C2—C9—H9B | 109.5 |
C3—C4—C5 | 120.0 (6) | H9A—C9—H9B | 109.5 |
C3—C4—H4 | 120.0 | C2—C9—H9C | 109.5 |
C5—C4—H4 | 120.0 | H9A—C9—H9C | 109.5 |
C4—C5—C6 | 119.5 (6) | H9B—C9—H9C | 109.5 |
C4—C5—H5 | 120.3 | C7—N1—C1 | 124.3 (4) |
C6—C5—H5 | 120.3 | C7—N1—H1N | 121 (4) |
C5—C6—C1 | 120.5 (5) | C1—N1—H1N | 114 (4) |
C5—C6—H6 | 119.7 | ||
C6—C1—C2—C3 | −1.2 (9) | C3—C4—C5—C6 | −0.3 (11) |
N1—C1—C2—C3 | 178.9 (5) | C4—C5—C6—C1 | −0.3 (10) |
C6—C1—C2—C9 | 175 (2) | C2—C1—C6—C5 | 1.1 (9) |
N1—C1—C2—C9 | −5 (2) | N1—C1—C6—C5 | −179.0 (6) |
C6—C1—C2—Cl1 | 178.0 (7) | O1—C7—C8—C8i | −28.1 (9) |
N1—C1—C2—Cl1 | −1.9 (9) | N1—C7—C8—C8i | 153.7 (6) |
C1—C2—C3—C4 | 0.6 (10) | O1—C7—N1—C1 | 4.3 (9) |
C9—C2—C3—C4 | −176 (2) | C8—C7—N1—C1 | −177.6 (5) |
Cl1—C2—C3—C4 | −178.7 (7) | C2—C1—N1—C7 | −64.2 (8) |
C2—C3—C4—C5 | 0.2 (11) | C6—C1—N1—C7 | 115.8 (6) |
Symmetry code: (i) −x+1, −y, −z. |
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O1ii | 0.85 (2) | 2.00 (2) | 2.846 (5) | 170 (5) |
Symmetry code: (ii) x, −y+1/2, z−1/2. |
Experimental details
Crystal data | |
Chemical formula | C17H17ClN2O2 |
Mr | 316.78 |
Crystal system, space group | Monoclinic, P21/c |
Temperature (K) | 293 |
a, b, c (Å) | 11.541 (3), 7.908 (2), 8.798 (2) |
β (°) | 102.55 (2) |
V (Å3) | 783.8 (3) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.25 |
Crystal size (mm) | 0.48 × 0.04 × 0.04 |
Data collection | |
Diffractometer | Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector |
Absorption correction | Multi-scan (CrysAlis RED; Oxford Diffraction, 2009) |
Tmin, Tmax | 0.889, 0.990 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 2598, 1391, 824 |
Rint | 0.044 |
(sin θ/λ)max (Å−1) | 0.599 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.105, 0.164, 1.28 |
No. of reflections | 1391 |
No. of parameters | 112 |
No. of restraints | 9 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.26, −0.31 |
Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1N···O1i | 0.853 (19) | 2.00 (2) | 2.846 (5) | 170 (5) |
Symmetry code: (i) x, −y+1/2, z−1/2. |
Acknowledgements
BSS thanks the University Grants Commission, Government of India, New Delhi for the award of a research fellowship under its faculty improvement programme.
References
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The amide and sulfonamide moieties are important constituents of many biologically significant compounds. As part of our studies on the substituent effects on the structures of this class of compounds (Bhat & Gowda, 2000; Gowda et al., 2007a,b; Saraswathi et al., 2011a,b,c), in the present work, the structure of N-(2-Chlorophenyl),N-(2-methylphenyl)-succinamide (I) has been determined (Fig.1). The asymmetric unit of (I) contains half a molecule with a center of symmetry at the mid-point of the central C—C bond, similar to that obseved in bis(2-chlorophenylaminocarbonylmethyl)disulfide (II) (Pierrot et al., 1984), N-(3-Chlorophenyl),N-(3-methylphenyl)- succinamide (III) (Saraswathi et al., 2011c), N,N-bis(2-chlorophenyl)-succinamide (IV) (Saraswathi et al., 2011b) and N,N-bis(2-methylphenyl)-succinamide dihydrate (V) (Saraswathi et al., 2011a).
The conformations of the amide O atoms are anti to the H atoms attached to the adjacent C atoms. Further, the conformations of the N—H bonds in the amide fragments are anti to the ortho- chloro/methyl groups in the adjacent benzene rings, similar to that observed with respect to the meta-chloro/methyl groups in (III), and the anti conformations observed with respect to the ortho-methyl groups in (V), but contrary to the syn conformations observed between the N—H bonds in the amide fragments and the ortho-chloro groups in the adjacent benzene rings of (IV).
Further, C1—N1—C7—C8 and C1a—N1a—C7a—C8a segments in (I) are nearly linear, similar to those observed in (III), (IV) and (V). The torsion angles of C2—C1—N1—C7 and C6—C1—N1—C7 are -64.3 (8)° and 115.8 (6)°, compared to the values of -43.2 (4)° and 138.6 (3)° in (III), -47.6 (6)° and 133.7 (4)° in (IV) and -64.0 (4)° and 117.6 (3)° in (V).
The dihedral angle between the benzene ring and the NH—C(O)—CH2 segment in the two halves of the molecule is 62.0 (2)°, compared to the values of 43.5 (1)° in (III), 47.0 (2)° in (IV) and 62.1 (2)° in (V).
The packing of molecules in the crystal linked by of N—H···O hydrogen bonds (Table 1) is shown in Fig. 2.