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ISSN: 2056-9890

N,N′-Bis(4-chloro­phen­yl)male­amide

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 9 May 2011; accepted 10 May 2011; online 14 May 2011)

In the crystal of the title compound, C16H12Cl2N2O2, the two C=O groups are anti to each other, while one of them is syn and the other is anti to their adjacent C—H bonds. The two benzene rings are oriented at an inter­planar angle of 56.4 (1)°, while the dihedral angles between the central amide group (N–C–C–C–C–N) and these rings are 3.6 (1) and 54.1 (1)°. An intra­molecular N—H⋯O hydrogen bond occurs. In the crystal, inter­molecular N—H⋯O hydrogen bonds link the mol­ecules into infinite chains along the a axis.

Related literature

For our study of the effect of substituents on the structures of N-(ar­yl)-amides, see: Gowda et al. (2004[Gowda, B. T., Svoboda, I. & Fuess, H. (2004). Z. Naturforsch. Teil A, 55, 845-852.], 2011[Gowda, B. T., Foro, S., Shakuntala, K. & Fuess, H. (2011). Acta Cryst. E67, o117.]) and on the structures of N-(ar­yl)-methane­sulfonamides, see: Gowda et al. (2007[Gowda, B. T., Foro, S. & Fuess, H. (2007). Acta Cryst. E63, o2597.]).

[Scheme 1]

Experimental

Crystal data
  • C16H12Cl2N2O2

  • Mr = 335.18

  • Monoclinic, P 21 /n

  • a = 9.2397 (7) Å

  • b = 13.0154 (8) Å

  • c = 13.1239 (9) Å

  • β = 107.916 (9)°

  • V = 1501.73 (18) Å3

  • Z = 4

  • Mo Kα radiation

  • μ = 0.44 mm−1

  • T = 293 K

  • 0.44 × 0.44 × 0.32 mm

Data collection
  • Oxford Diffraction Xcalibur diffractometer with a Sapphire CCD detector

  • Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]) Tmin = 0.830, Tmax = 0.872

  • 6063 measured reflections

  • 3065 independent reflections

  • 2523 reflections with I > 2σ(I)

  • Rint = 0.011

Refinement
  • R[F2 > 2σ(F2)] = 0.033

  • wR(F2) = 0.091

  • S = 1.06

  • 3065 reflections

  • 205 parameters

  • 2 restraints

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

  • Δρmax = 0.22 e Å−3

  • Δρmin = −0.24 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1N⋯O2i 0.84 (1) 2.05 (2) 2.8836 (16) 169 (2)
N2—H2N⋯O1 0.86 (1) 1.83 (2) 2.6639 (17) 162 (2)
Symmetry code: (i) [-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}].

Data collection: CrysAlis CCD (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); cell refinement: CrysAlis RED (Oxford Diffraction, 2009[Oxford Diffraction (2009). CrysAlis CCD and CrysAlis RED. Oxford Diffraction Ltd, Yarnton, England.]); 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.]); molecular graphics: PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

The amide moiety is an important constituent of many biologically significant compounds. As a part of studying the effect of substitutions on the structures of this class of compounds (Gowda et al., 2004, 2007, 2011), the crystal structure of N,N-bis(4-chlorophenyl)-maleamide has been determined (I) (Fig. 1). In the structure, the conformations of N—H and C=O bonds in both the amide groups of the C—NH—CO—CH CH—CO—NH—C segment are anti to each other. The two C=O bonds are also anti to each other, while one of them is syn to the adjacent C—H bond and the other is anti to its adjacent C—H bond, similar to that observed in N,N-bis(phenyl)-maleamide (II) (Gowda et al., 2011).

Further, C1—N1—C7—C8 and C11—N2—C10—C9 segments are nearly linear. The torsion angles of C2—C1—N1—C7 and C6—C1—N1—C7 are -7.0 (3)° and 174.2 (2)°, respectively, compared to the values of 174.4 (3)° and -4.9 (4)° in (II). The torsion angles of C12—C11—N2—C10 and C16—C11—N2—C10 are 122.7 (2)° and -59.1 (2)°, in contrast to the values of 40.4 (4)° and -143.9 (3)° in (II).

The two phenyl rings in (I) make an interplanar angle of 56.4 (1)°, compared to the value of 41.2 (1)° in (II). The two benzene rings (C1 to C6 and C11 to C16) make the dihedral angles of 3.6 (1)° and 54.1 (1)°, respectively, with the central amide group (N1—C7—C8—C9—C10—N2), compared to the corresponding values of 8.0 (1)° and 38.3 (1)° in (II).

The crystal structure exhibits both the intramolecular and intermolecular N–H···O hydrogen bonding (Table 1). The packing of molecules through intermolecular N–H···O hydrogen bonds is shown in Fig. 2.

Related literature top

For our study of the effect of substituents on the structures of N-(aryl)-amides, see: Gowda et al. (2004, 2011) and on the structures of N-(aryl)-methanesulfonamides, see: Gowda et al. (2007).

Experimental top

A mixture of maleic acid (0.2 mol) and phosphorous oxy chloride (0.3 mol) were refluxed for 3 hrs on a water bath at 95° C. 4-Chloroaniline was added dropwise with stirring and continuing heating for about 30 min. It was later kept aside for 12 hrs for completion of the reaction. The reaction mixture was then added to ice. The precipitated product was washed with water, dilute HCl, dilute NaOH and again with water. The product was filtered, dried and recrystallized from DMF.

Prism like dark-grey single crystals of the title compound used in X-ray diffraction studies were obtained by a slow evaporation of its DMF solution at room temperature.

Refinement top

The H atoms of the NH groups were 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 C—H = 0.93 Å. All H atoms were refined with isotropic displacement parameters (set to 1.2 times of the Ueq of the parent atom).

Computing details top

Data collection: CrysAlis CCD (Oxford Diffraction, 2009); cell refinement: 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).

Figures top
[Figure 1] Fig. 1. Molecular structure of (I), showing the atom labelling scheme and displacement ellipsoids are drawn at the 50% probability level. Hydrogen bonding is shown as dashed line.
[Figure 2] Fig. 2. Molecular packing of (I) with hydrogen bonding shown as dashed lines.
N,N'-bis(4-chlorophenyl)but-2-enediamide top
Crystal data top
C16H12Cl2N2O2F(000) = 688
Mr = 335.18Dx = 1.482 Mg m3
Monoclinic, P21/nMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ynCell parameters from 3188 reflections
a = 9.2397 (7) Åθ = 2.8–27.9°
b = 13.0154 (8) ŵ = 0.44 mm1
c = 13.1239 (9) ÅT = 293 K
β = 107.916 (9)°Prism, dark grey
V = 1501.73 (18) Å30.44 × 0.44 × 0.32 mm
Z = 4
Data collection top
Oxford Diffraction Xcalibur
diffractometer with a Sapphire CCD detector
3065 independent reflections
Radiation source: fine-focus sealed tube2523 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.011
Rotation method data acquisition using ω scansθmax = 26.4°, θmin = 2.8°
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
h = 1110
Tmin = 0.830, Tmax = 0.872k = 1416
6063 measured reflectionsl = 1611
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)] = 0.033Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.091H atoms treated by a mixture of independent and constrained refinement
S = 1.06 w = 1/[σ2(Fo2) + (0.0494P)2 + 0.3163P]
where P = (Fo2 + 2Fc2)/3
3065 reflections(Δ/σ)max = 0.001
205 parametersΔρmax = 0.22 e Å3
2 restraintsΔρmin = 0.24 e Å3
Crystal data top
C16H12Cl2N2O2V = 1501.73 (18) Å3
Mr = 335.18Z = 4
Monoclinic, P21/nMo Kα radiation
a = 9.2397 (7) ŵ = 0.44 mm1
b = 13.0154 (8) ÅT = 293 K
c = 13.1239 (9) Å0.44 × 0.44 × 0.32 mm
β = 107.916 (9)°
Data collection top
Oxford Diffraction Xcalibur
diffractometer with a Sapphire CCD detector
3065 independent reflections
Absorption correction: multi-scan
(CrysAlis RED; Oxford Diffraction, 2009)
2523 reflections with I > 2σ(I)
Tmin = 0.830, Tmax = 0.872Rint = 0.011
6063 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0332 restraints
wR(F2) = 0.091H atoms treated by a mixture of independent and constrained refinement
S = 1.06Δρmax = 0.22 e Å3
3065 reflectionsΔρmin = 0.24 e Å3
205 parameters
Special details top

Experimental. CrysAlis RED (Oxford Diffraction, 2009) 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
Cl11.02985 (5)0.18771 (4)0.07433 (4)0.05576 (15)
Cl20.34374 (6)0.72529 (3)0.01488 (4)0.06130 (16)
O10.49648 (15)0.13865 (8)0.14544 (12)0.0566 (4)
O20.10969 (14)0.32142 (8)0.19093 (9)0.0449 (3)
N10.49484 (15)0.03027 (10)0.18426 (11)0.0380 (3)
H1N0.4540 (19)0.0748 (13)0.2131 (13)0.046*
N20.30826 (16)0.29745 (10)0.12704 (11)0.0393 (3)
H2N0.3780 (18)0.2545 (14)0.1250 (14)0.047*
C10.62405 (17)0.06341 (11)0.15703 (12)0.0349 (3)
C20.7035 (2)0.00167 (13)0.10578 (14)0.0479 (4)
H20.67340.06600.08880.057*
C30.8268 (2)0.04074 (14)0.08021 (14)0.0479 (4)
H30.87990.00070.04620.057*
C40.87128 (18)0.14080 (13)0.10489 (12)0.0399 (4)
C50.79395 (19)0.20323 (12)0.15518 (13)0.0430 (4)
H50.82400.27110.17110.052*
C60.67118 (18)0.16405 (11)0.18174 (13)0.0391 (3)
H60.61960.20570.21660.047*
C70.43672 (17)0.06548 (11)0.17594 (12)0.0367 (3)
C80.29546 (19)0.07352 (12)0.20689 (13)0.0410 (4)
H80.26490.01300.23190.049*
C90.20588 (19)0.15430 (12)0.20424 (13)0.0423 (4)
H90.12310.13800.22740.051*
C100.20609 (17)0.26486 (11)0.17309 (11)0.0346 (3)
C110.31503 (17)0.40084 (11)0.09296 (12)0.0346 (3)
C120.44804 (17)0.45625 (12)0.13303 (12)0.0369 (3)
H120.53180.42610.18250.044*
C130.45728 (18)0.55621 (12)0.10004 (12)0.0386 (3)
H130.54690.59350.12670.046*
C140.33194 (18)0.59989 (11)0.02710 (12)0.0371 (3)
C150.19922 (18)0.54565 (13)0.01497 (13)0.0432 (4)
H150.11600.57590.06490.052*
C160.19120 (19)0.44518 (12)0.01807 (13)0.0421 (4)
H160.10240.40750.01020.051*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.0450 (2)0.0601 (3)0.0653 (3)0.0114 (2)0.0217 (2)0.0056 (2)
Cl20.0756 (3)0.0331 (2)0.0800 (3)0.0011 (2)0.0311 (3)0.0178 (2)
O10.0608 (8)0.0259 (6)0.1020 (10)0.0056 (5)0.0528 (7)0.0123 (6)
O20.0515 (7)0.0384 (6)0.0541 (7)0.0094 (5)0.0300 (5)0.0004 (5)
N10.0443 (7)0.0262 (6)0.0500 (7)0.0015 (5)0.0242 (6)0.0079 (5)
N20.0467 (8)0.0271 (6)0.0530 (8)0.0088 (6)0.0282 (6)0.0076 (6)
C10.0381 (8)0.0284 (7)0.0394 (8)0.0016 (6)0.0139 (6)0.0004 (6)
C20.0580 (10)0.0334 (8)0.0624 (10)0.0103 (8)0.0336 (9)0.0138 (8)
C30.0537 (10)0.0436 (9)0.0549 (10)0.0034 (8)0.0293 (8)0.0084 (8)
C40.0377 (8)0.0421 (9)0.0393 (8)0.0044 (7)0.0108 (6)0.0068 (7)
C50.0449 (9)0.0310 (8)0.0511 (9)0.0061 (7)0.0116 (7)0.0008 (7)
C60.0435 (8)0.0282 (7)0.0463 (8)0.0024 (6)0.0147 (7)0.0022 (6)
C70.0425 (8)0.0262 (7)0.0460 (8)0.0014 (6)0.0206 (7)0.0033 (6)
C80.0500 (9)0.0293 (7)0.0523 (9)0.0001 (7)0.0285 (8)0.0075 (7)
C90.0490 (9)0.0373 (8)0.0515 (9)0.0015 (7)0.0315 (8)0.0064 (7)
C100.0415 (8)0.0313 (7)0.0353 (7)0.0034 (6)0.0180 (6)0.0005 (6)
C110.0433 (8)0.0271 (7)0.0403 (8)0.0060 (6)0.0231 (6)0.0030 (6)
C120.0389 (8)0.0381 (8)0.0364 (8)0.0076 (7)0.0154 (6)0.0060 (6)
C130.0417 (8)0.0358 (8)0.0421 (8)0.0028 (7)0.0183 (7)0.0009 (6)
C140.0489 (9)0.0269 (7)0.0430 (8)0.0043 (6)0.0252 (7)0.0052 (6)
C150.0414 (8)0.0396 (9)0.0486 (9)0.0087 (7)0.0140 (7)0.0113 (7)
C160.0386 (8)0.0350 (8)0.0525 (9)0.0001 (7)0.0136 (7)0.0040 (7)
Geometric parameters (Å, º) top
Cl1—C41.7440 (16)C5—H50.9300
Cl2—C141.7367 (15)C6—H60.9300
O1—C71.2280 (18)C7—C81.485 (2)
O2—C101.2322 (18)C8—C91.332 (2)
N1—C71.3481 (19)C8—H80.9300
N1—C11.4149 (19)C9—C101.496 (2)
N1—H1N0.843 (14)C9—H90.9300
N2—C101.3369 (19)C11—C121.382 (2)
N2—C111.4255 (19)C11—C161.384 (2)
N2—H2N0.860 (14)C12—C131.382 (2)
C1—C61.387 (2)C12—H120.9300
C1—C21.393 (2)C13—C141.378 (2)
C2—C31.380 (2)C13—H130.9300
C2—H20.9300C14—C151.375 (2)
C3—C41.374 (2)C15—C161.387 (2)
C3—H30.9300C15—H150.9300
C4—C51.377 (2)C16—H160.9300
C5—C61.383 (2)
C7—N1—C1127.41 (13)C9—C8—C7129.78 (14)
C7—N1—H1N116.8 (13)C9—C8—H8115.1
C1—N1—H1N115.7 (13)C7—C8—H8115.1
C10—N2—C11123.13 (13)C8—C9—C10135.51 (14)
C10—N2—H2N116.6 (13)C8—C9—H9112.2
C11—N2—H2N119.9 (13)C10—C9—H9112.2
C6—C1—C2118.92 (14)O2—C10—N2123.26 (14)
C6—C1—N1117.23 (13)O2—C10—C9117.45 (13)
C2—C1—N1123.84 (14)N2—C10—C9119.29 (13)
C3—C2—C1120.13 (15)C12—C11—C16119.78 (14)
C3—C2—H2119.9C12—C11—N2119.54 (14)
C1—C2—H2119.9C16—C11—N2120.66 (14)
C4—C3—C2120.08 (16)C11—C12—C13120.37 (14)
C4—C3—H3120.0C11—C12—H12119.8
C2—C3—H3120.0C13—C12—H12119.8
C3—C4—C5120.71 (15)C14—C13—C12119.10 (15)
C3—C4—Cl1119.28 (13)C14—C13—H13120.5
C5—C4—Cl1120.00 (13)C12—C13—H13120.5
C4—C5—C6119.34 (15)C15—C14—C13121.49 (14)
C4—C5—H5120.3C15—C14—Cl2119.37 (12)
C6—C5—H5120.3C13—C14—Cl2119.12 (12)
C5—C6—C1120.82 (15)C14—C15—C16119.04 (15)
C5—C6—H6119.6C14—C15—H15120.5
C1—C6—H6119.6C16—C15—H15120.5
O1—C7—N1122.38 (14)C11—C16—C15120.21 (15)
O1—C7—C8123.75 (14)C11—C16—H16119.9
N1—C7—C8113.87 (13)C15—C16—H16119.9
C7—N1—C1—C6174.16 (15)C11—N2—C10—O20.6 (3)
C7—N1—C1—C27.0 (3)C11—N2—C10—C9178.80 (14)
C6—C1—C2—C30.1 (3)C8—C9—C10—O2173.19 (19)
N1—C1—C2—C3178.74 (16)C8—C9—C10—N27.4 (3)
C1—C2—C3—C40.2 (3)C10—N2—C11—C12122.66 (17)
C2—C3—C4—C50.0 (3)C10—N2—C11—C1659.1 (2)
C2—C3—C4—Cl1178.68 (14)C16—C11—C12—C131.0 (2)
C3—C4—C5—C60.6 (2)N2—C11—C12—C13179.29 (13)
Cl1—C4—C5—C6178.10 (12)C11—C12—C13—C140.3 (2)
C4—C5—C6—C10.9 (2)C12—C13—C14—C151.3 (2)
C2—C1—C6—C50.7 (2)C12—C13—C14—Cl2179.70 (11)
N1—C1—C6—C5178.25 (14)C13—C14—C15—C160.9 (2)
C1—N1—C7—O12.6 (3)Cl2—C14—C15—C16179.31 (12)
C1—N1—C7—C8177.38 (14)C12—C11—C16—C151.4 (2)
O1—C7—C8—C93.0 (3)N2—C11—C16—C15179.66 (14)
N1—C7—C8—C9176.98 (17)C14—C15—C16—C110.5 (2)
C7—C8—C9—C100.8 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O2i0.84 (1)2.05 (2)2.8836 (16)169 (2)
N2—H2N···O10.86 (1)1.83 (2)2.6639 (17)162 (2)
Symmetry code: (i) x+1/2, y1/2, z+1/2.

Experimental details

Crystal data
Chemical formulaC16H12Cl2N2O2
Mr335.18
Crystal system, space groupMonoclinic, P21/n
Temperature (K)293
a, b, c (Å)9.2397 (7), 13.0154 (8), 13.1239 (9)
β (°) 107.916 (9)
V3)1501.73 (18)
Z4
Radiation typeMo Kα
µ (mm1)0.44
Crystal size (mm)0.44 × 0.44 × 0.32
Data collection
DiffractometerOxford Diffraction Xcalibur
diffractometer with a Sapphire CCD detector
Absorption correctionMulti-scan
(CrysAlis RED; Oxford Diffraction, 2009)
Tmin, Tmax0.830, 0.872
No. of measured, independent and
observed [I > 2σ(I)] reflections
6063, 3065, 2523
Rint0.011
(sin θ/λ)max1)0.625
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.033, 0.091, 1.06
No. of reflections3065
No. of parameters205
No. of restraints2
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.22, 0.24

Computer programs: CrysAlis CCD (Oxford Diffraction, 2009), CrysAlis RED (Oxford Diffraction, 2009), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1N···O2i0.843 (14)2.052 (15)2.8836 (16)168.9 (17)
N2—H2N···O10.860 (14)1.833 (15)2.6639 (17)161.7 (18)
Symmetry code: (i) x+1/2, y1/2, z+1/2.
 

Acknowledgements

KS thanks the University Grants Commission, Government of India, New Delhi, for the award of a research fellowship under its faculty improvement program.

References

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