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ISSN: 2056-9890

Ethyl N-(2-benzoyl-4-chloro­phen­yl)­ethane­carboximidate

aDepartment of Studies in Chemistry, University of Mysore, Mysore 570 006, India, and bDepartment of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland
*Correspondence e-mail: mkubicki@amu.edu.pl

(Received 1 February 2012; accepted 21 February 2012; online 29 February 2012)

In the title compound, C17H16ClNO2, the N=C—O—C—C fragment is planar within 0.029 (1) Å, and makes dihedral angles of 66.71 (8) and 59.61 (8)° with the planes of the chloro­phenyl and benzoyl rings, respectively. The carbonyl C=O bond is not coplanar with either of the aromatic rings; it makes angles of 42.5 and 23.5° with the normals to the ring planes. In the crystal, very weak C—H⋯O, C—H⋯Cl, C—H⋯π and ππ [inter­planar distance = 3.53 (1) Å] inter­actions are observed.

Related literature

For background to the medical applications of benzophenones, see, for instance: Evans et al. (1987[Evans, D., Cracknell, M. E., Saunders, J. C., Smith, C. E., Willamson, W. R. N., Dowson, W. & Sweatman, W. J. F. (1987). J. Med. Chem. 30, 1321-1327.]); Revesz et al. (2004[Revesz, L., Blum, E., Di Padova, F. E., Buhl, T., Feifel, R., Gram, H., Hiestand, P., Manning, U. & Rucklin, G. (2004). Bioorg. Med. Chem. Lett. 14, 3601-3605.]); Wiesner et al. (2002[Wiesner, J., Kettler, K., Jomaa, H. & Schlitzer, M. (2002). Bioorg. Med. Chem. Lett. 12, 543-545.]); Zeng et al. (2010[Zeng, Z. S., He, Q. Q., Liang, Y. H., Chen, F. E., De Clercq, E., Balzarini, J. & Pannecouque, C. (2010). Bioorg. Med. Chem. 18, 5039-5047.]). A similar structure has been described by Derieg et al. (1970[Derieg, M. E., Blount, J. F., Fryer, R. I. & Hillery, S. S. (1970). Tetrahedron Lett. 11, 3869-3872.])

[Scheme 1]

Experimental

Crystal data
  • C17H16ClNO2

  • Mr = 301.76

  • Triclinic, [P \overline 1]

  • a = 7.9674 (11) Å

  • b = 8.6993 (17) Å

  • c = 11.596 (2) Å

  • α = 104.499 (17)°

  • β = 94.871 (14)°

  • γ = 95.001 (14)°

  • V = 770.4 (2) Å3

  • Z = 2

  • Mo Kα radiation

  • μ = 0.25 mm−1

  • T = 295 K

  • 0.35 × 0.2 × 0.15 mm

Data collection
  • Agilent Xcalibur Eos diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.]) Tmin = 0.991, Tmax = 1.000

  • 13278 measured reflections

  • 3377 independent reflections

  • 2455 reflections with I > 2σ(I)

  • Rint = 0.028

Refinement
  • R[F2 > 2σ(F2)] = 0.044

  • wR(F2) = 0.117

  • S = 1.05

  • 3377 reflections

  • 192 parameters

  • H-atom parameters constrained

  • Δρmax = 0.20 e Å−3

  • Δρmin = −0.21 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

CgA denotes the centroid of the phenyl ring C1–C6.

D—H⋯A D—H H⋯A DA D—H⋯A
C5—H5⋯O22i 0.93 2.80 3.704 (2) 164
C6—H6⋯O14ii 0.93 2.73 3.648 (2) 172
C16—H16B⋯O22iii 0.96 2.66 3.614 (3) 171
C27—H27⋯Cl4iv 0.93 2.88 3.739 (2) 154
C25—H25⋯CgAv 0.93 2.90 3.744 (3) 151
Symmetry codes: (i) x, y+1, z; (ii) -x+2, -y+1, -z+1; (iii) x+1, y, z; (iv) x+1, y-1, z; (v) -x+2, -y+1, -z+2.

Data collection: CrysAlis PRO (Agilent, 2011[Agilent (2011). CrysAlis PRO. Agilent Technologies, Yarnton, Oxfordshire, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR92 (Altomare et al., 1993[Altomare, A., Cascarano, G., Giacovazzo, C. & Guagliardi, A. (1993). J. Appl. Cryst. 26, 343-350.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: XP (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); software used to prepare material for publication: SHELXL97.

Supporting information


Comment top

Benzophenone and related analogues have been reported to act as antiallergic, anti-inflammatory, antiasthamatic, antimalarial, anti-microbial and antianaphylactic agents (Evans et al., 1987; Wiesner et al., 2002). The competence of benzophenones as chemotherapeutic agents, especially as inhibitors of HIV-1 reverse transcriptase RT, cancer and inflammation, is well established and their chemistry has been studied extensively (Revesz et al., 2004, Zeng et al., 2010). The title compound - N-(2-Benzoyl-4-chloro-phenyl)-acetimidic acid ethyl ester (1, Scheme 1) - is an intermediate in the synthesis of certain anxiolytic, anticonvulsant and sedative drugs.

The conformation of N-(2-Benzoyl-4-chloro-phenyl)-acetimidic acid ethyl ester (1, Scheme 1) can be described by the dihedral angles between the approximately planar fragments: two aromatic rings (A and B, cf. Fig. 1), and the N=C—O—C—C chain (C, which is planar within 0.029 (1) Å). All these angles are close to 60°: A/B 69.14 (5) °, A/C 66.71 (8) °, B/C 59.61 (8) °. Interestingly, the C21=O22 double bond is not coplanar with either A or B phenyl rings, the C2—C21(=O22)—C23 plane makes the dihedral angle 52.81 (6) ° with the ring A and 25.51 (8) ° with ring B. Quite similar conformation was observed in the crystal structure of related compound, 2-benzoyl-4-chloroformanilide triacetylhydrazide (Derieg et al., 1970).

In the crystal only some weak but directional C—H···O, C—H···Cl and C—H···π interaction can be found (cf. Table), and they to some extent influence the packing together with van der Waals interactions. Also the phenyl rings B from molecules related by the center of symmetry stack to some extent with the interplanar distance of ca 3.53 Å.

Related literature top

For general references on medical applications of benzophenones, see, for instance: Evans et al. (1987); Revesz et al. (2004); Wiesner et al. (2002); Zeng et al. (2010). A similar structure has been described by Derieg et al. (1970)

Experimental top

The title compound was obtained as a gift sample from R. L. Fine Chem., Bengaluru, India. The compound was recrystallized from dichloromethane by slow evaporation (m.p: 323 K).

Refinement top

Hydrogen atoms were put in the idealized positions, and refined as riding model. Their isotropic thermal parameters were set at 1.2 times Ueq's of appropriate carrier atoms.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); program(s) used to solve structure: SIR92 (Altomare et al., 1993); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP (Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Anisotropic ellipsoid representation of 1, drawn at 50% probability level.
[Figure 2] Fig. 2. The crystal packing as seen approximately along the a-axis direction. Weak C—H···Cl hydrogen bonds are depicted as dashed lines.
Ethyl N-(2-benzoyl-4-chlorophenyl)ethanecarboximidate top
Crystal data top
C17H16ClNO2Z = 2
Mr = 301.76F(000) = 316
Triclinic, P1Dx = 1.301 Mg m3
Hall symbol: -P 1Mo Kα radiation, λ = 0.7107 Å
a = 7.9674 (11) ÅCell parameters from 1885 reflections
b = 8.6993 (17) Åθ = 2.9–27.8°
c = 11.596 (2) ŵ = 0.25 mm1
α = 104.499 (17)°T = 295 K
β = 94.871 (14)°Block, colourless
γ = 95.001 (14)°0.35 × 0.2 × 0.15 mm
V = 770.4 (2) Å3
Data collection top
Agilent Xcalibur Eos
diffractometer
3377 independent reflections
Radiation source: Enhance (Mo) X-ray Source2455 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.028
Detector resolution: 16.1544 pixels mm-1θmax = 28.2°, θmin = 3.0°
ω–scanh = 1010
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
k = 1111
Tmin = 0.991, Tmax = 1.000l = 1515
13278 measured reflections
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)] = 0.044Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.117H-atom parameters constrained
S = 1.05 w = 1/[σ2(Fo2) + (0.0479P)2 + 0.1642P]
where P = (Fo2 + 2Fc2)/3
3377 reflections(Δ/σ)max = 0.001
192 parametersΔρmax = 0.20 e Å3
0 restraintsΔρmin = 0.21 e Å3
Crystal data top
C17H16ClNO2γ = 95.001 (14)°
Mr = 301.76V = 770.4 (2) Å3
Triclinic, P1Z = 2
a = 7.9674 (11) ÅMo Kα radiation
b = 8.6993 (17) ŵ = 0.25 mm1
c = 11.596 (2) ÅT = 295 K
α = 104.499 (17)°0.35 × 0.2 × 0.15 mm
β = 94.871 (14)°
Data collection top
Agilent Xcalibur Eos
diffractometer
3377 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2011)
2455 reflections with I > 2σ(I)
Tmin = 0.991, Tmax = 1.000Rint = 0.028
13278 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0440 restraints
wR(F2) = 0.117H-atom parameters constrained
S = 1.05Δρmax = 0.20 e Å3
3377 reflectionsΔρmin = 0.21 e Å3
192 parameters
Special details top

Experimental. Address for R L Fine Chemicals:

No 15, R L Fine Chem, KHB Industrial Area, Yelahanka New Town, Bengaluru-560 106, India. Website: http://www.rlfinechem.com

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
C10.7628 (2)0.41768 (19)0.70454 (14)0.0376 (4)
C20.6659 (2)0.33697 (19)0.77071 (14)0.0361 (4)
C30.5286 (2)0.4041 (2)0.82141 (15)0.0411 (4)
H30.46010.34840.86190.049*
C40.4940 (2)0.5531 (2)0.81170 (15)0.0422 (4)
Cl40.32629 (7)0.63863 (7)0.87998 (5)0.0670 (2)
C50.5910 (2)0.6367 (2)0.74955 (16)0.0464 (4)
H50.56710.73740.74390.056*
C60.7238 (2)0.5683 (2)0.69612 (16)0.0463 (4)
H60.78900.62360.65350.056*
N110.90172 (18)0.34957 (17)0.65447 (13)0.0428 (4)
C120.9091 (2)0.3070 (2)0.54356 (16)0.0432 (4)
C130.7813 (3)0.3131 (3)0.44432 (18)0.0663 (6)
H13A0.68190.35280.47680.099*
H13B0.75170.20770.39230.099*
H13C0.82780.38280.39970.099*
O141.04660 (16)0.24308 (16)0.50072 (10)0.0514 (3)
C151.1748 (3)0.2175 (3)0.58734 (18)0.0611 (6)
H15A1.12480.15280.63530.073*
H15B1.22420.31910.64040.073*
C161.3068 (3)0.1356 (3)0.5231 (2)0.0828 (8)
H16A1.25580.03870.46680.124*
H16B1.38850.11070.57940.124*
H16C1.36210.20400.48100.124*
C210.7012 (2)0.1754 (2)0.78588 (15)0.0398 (4)
O220.58787 (18)0.06586 (16)0.76157 (14)0.0632 (4)
C230.8739 (2)0.15418 (19)0.83424 (14)0.0368 (4)
C240.9812 (2)0.2816 (2)0.90603 (16)0.0455 (4)
H240.94790.38400.92170.055*
C251.1373 (3)0.2576 (3)0.95454 (18)0.0587 (5)
H251.20780.34321.00490.070*
C261.1892 (3)0.1075 (3)0.9288 (2)0.0655 (6)
H261.29510.09170.96130.079*
C271.0850 (3)0.0190 (3)0.8554 (2)0.0672 (6)
H271.12140.12020.83650.081*
C280.9271 (3)0.0033 (2)0.80965 (18)0.0533 (5)
H280.85540.08350.76190.064*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
C10.0369 (9)0.0398 (9)0.0377 (9)0.0072 (7)0.0026 (7)0.0122 (7)
C20.0353 (9)0.0371 (8)0.0365 (8)0.0070 (7)0.0002 (7)0.0111 (7)
C30.0375 (9)0.0466 (10)0.0428 (9)0.0092 (8)0.0051 (8)0.0165 (8)
C40.0411 (10)0.0466 (10)0.0420 (9)0.0175 (8)0.0043 (8)0.0133 (8)
Cl40.0666 (4)0.0787 (4)0.0720 (4)0.0447 (3)0.0256 (3)0.0314 (3)
C50.0540 (11)0.0403 (9)0.0498 (10)0.0164 (9)0.0026 (9)0.0181 (8)
C60.0505 (11)0.0437 (10)0.0520 (10)0.0090 (9)0.0088 (9)0.0235 (8)
N110.0417 (8)0.0502 (9)0.0418 (8)0.0141 (7)0.0086 (7)0.0174 (7)
C120.0384 (10)0.0510 (10)0.0443 (10)0.0086 (8)0.0075 (8)0.0175 (8)
C130.0553 (13)0.0958 (17)0.0489 (11)0.0261 (12)0.0009 (10)0.0165 (11)
O140.0427 (7)0.0750 (9)0.0404 (7)0.0197 (7)0.0082 (6)0.0165 (6)
C150.0527 (12)0.0842 (15)0.0502 (11)0.0284 (11)0.0031 (10)0.0184 (10)
C160.0640 (15)0.118 (2)0.0739 (15)0.0435 (15)0.0100 (13)0.0262 (15)
C210.0429 (10)0.0360 (9)0.0418 (9)0.0070 (8)0.0063 (8)0.0112 (7)
O220.0490 (8)0.0447 (7)0.0956 (11)0.0023 (7)0.0048 (8)0.0242 (7)
C230.0421 (10)0.0353 (8)0.0375 (9)0.0108 (7)0.0074 (7)0.0145 (7)
C240.0478 (11)0.0410 (9)0.0480 (10)0.0105 (8)0.0025 (9)0.0114 (8)
C250.0486 (12)0.0701 (14)0.0584 (12)0.0067 (10)0.0065 (10)0.0223 (10)
C260.0476 (12)0.0906 (17)0.0721 (14)0.0281 (12)0.0055 (11)0.0404 (13)
C270.0729 (15)0.0616 (13)0.0798 (15)0.0405 (13)0.0148 (13)0.0286 (12)
C280.0621 (13)0.0387 (10)0.0623 (12)0.0166 (9)0.0062 (10)0.0154 (9)
Geometric parameters (Å, º) top
C1—C21.398 (2)C15—C161.472 (3)
C1—C61.398 (2)C15—H15A0.9700
C1—N111.402 (2)C15—H15B0.9700
C2—C31.390 (2)C16—H16A0.9600
C2—C211.506 (2)C16—H16B0.9600
C3—C41.379 (2)C16—H16C0.9600
C3—H30.9300C21—O221.214 (2)
C4—C51.380 (3)C21—C231.486 (2)
C4—Cl41.7391 (17)C23—C241.380 (2)
C5—C61.376 (2)C23—C281.383 (2)
C5—H50.9300C24—C251.375 (3)
C6—H60.9300C24—H240.9300
N11—C121.254 (2)C25—C261.373 (3)
C12—O141.348 (2)C25—H250.9300
C12—C131.485 (3)C26—C271.370 (3)
C13—H13A0.9600C26—H260.9300
C13—H13B0.9600C27—C281.372 (3)
C13—H13C0.9600C27—H270.9300
O14—C151.442 (2)C28—H280.9300
C2—C1—C6118.80 (15)C16—C15—H15A109.9
C2—C1—N11119.15 (14)O14—C15—H15B109.9
C6—C1—N11121.95 (16)C16—C15—H15B109.9
C3—C2—C1119.58 (15)H15A—C15—H15B108.3
C3—C2—C21118.18 (15)C15—C16—H16A109.5
C1—C2—C21122.20 (15)C15—C16—H16B109.5
C4—C3—C2120.03 (16)H16A—C16—H16B109.5
C4—C3—H3120.0C15—C16—H16C109.5
C2—C3—H3120.0H16A—C16—H16C109.5
C3—C4—C5121.20 (16)H16B—C16—H16C109.5
C3—C4—Cl4119.55 (14)O22—C21—C23120.95 (16)
C5—C4—Cl4119.25 (13)O22—C21—C2119.91 (16)
C6—C5—C4118.86 (16)C23—C21—C2119.12 (15)
C6—C5—H5120.6C24—C23—C28119.14 (17)
C4—C5—H5120.6C24—C23—C21121.28 (15)
C5—C6—C1121.44 (17)C28—C23—C21119.57 (16)
C5—C6—H6119.3C25—C24—C23120.16 (17)
C1—C6—H6119.3C25—C24—H24119.9
C12—N11—C1122.68 (15)C23—C24—H24119.9
N11—C12—O14119.97 (16)C26—C25—C24120.2 (2)
N11—C12—C13129.03 (17)C26—C25—H25119.9
O14—C12—C13110.99 (15)C24—C25—H25119.9
C12—C13—H13A109.5C27—C26—C25120.0 (2)
C12—C13—H13B109.5C27—C26—H26120.0
H13A—C13—H13B109.5C25—C26—H26120.0
C12—C13—H13C109.5C26—C27—C28120.08 (19)
H13A—C13—H13C109.5C26—C27—H27120.0
H13B—C13—H13C109.5C28—C27—H27120.0
C12—O14—C15116.82 (14)C27—C28—C23120.4 (2)
O14—C15—C16108.70 (17)C27—C28—H28119.8
O14—C15—H15A109.9C23—C28—H28119.8
C6—C1—C2—C33.2 (2)C13—C12—O14—C15174.91 (18)
N11—C1—C2—C3179.56 (15)C12—O14—C15—C16175.44 (19)
C6—C1—C2—C21179.05 (16)C3—C2—C21—O2250.6 (2)
N11—C1—C2—C212.6 (2)C1—C2—C21—O22127.22 (19)
C1—C2—C3—C43.4 (2)C3—C2—C21—C23127.49 (17)
C21—C2—C3—C4178.69 (16)C1—C2—C21—C2354.7 (2)
C2—C3—C4—C51.7 (3)O22—C21—C23—C24153.15 (17)
C2—C3—C4—Cl4177.78 (13)C2—C21—C23—C2424.9 (2)
C3—C4—C5—C60.4 (3)O22—C21—C23—C2825.1 (3)
Cl4—C4—C5—C6179.81 (14)C2—C21—C23—C28156.77 (16)
C4—C5—C6—C10.6 (3)C28—C23—C24—C251.5 (3)
C2—C1—C6—C51.2 (3)C21—C23—C24—C25176.78 (17)
N11—C1—C6—C5177.46 (16)C23—C24—C25—C262.0 (3)
C2—C1—N11—C12116.53 (19)C24—C25—C26—C270.5 (3)
C6—C1—N11—C1267.2 (2)C25—C26—C27—C281.5 (3)
C1—N11—C12—O14179.59 (15)C26—C27—C28—C232.0 (3)
C1—N11—C12—C131.7 (3)C24—C23—C28—C270.5 (3)
N11—C12—O14—C154.1 (3)C21—C23—C28—C27178.80 (18)
Hydrogen-bond geometry (Å, º) top
CgA denotes the centroid of the phenyl ring C1 - C6
D—H···AD—HH···AD···AD—H···A
C5—H5···O22i0.932.803.704 (2)164
C6—H6···O14ii0.932.733.648 (2)172
C16—H16B···O22iii0.962.663.614 (3)171
C27—H27···Cl4iv0.932.883.739 (2)154
C25—H25···CgAv0.932.903.744 (3)151
Symmetry codes: (i) x, y+1, z; (ii) x+2, y+1, z+1; (iii) x+1, y, z; (iv) x+1, y1, z; (v) x+2, y+1, z+2.

Experimental details

Crystal data
Chemical formulaC17H16ClNO2
Mr301.76
Crystal system, space groupTriclinic, P1
Temperature (K)295
a, b, c (Å)7.9674 (11), 8.6993 (17), 11.596 (2)
α, β, γ (°)104.499 (17), 94.871 (14), 95.001 (14)
V3)770.4 (2)
Z2
Radiation typeMo Kα
µ (mm1)0.25
Crystal size (mm)0.35 × 0.2 × 0.15
Data collection
DiffractometerAgilent Xcalibur Eos
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2011)
Tmin, Tmax0.991, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
13278, 3377, 2455
Rint0.028
(sin θ/λ)max1)0.664
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.044, 0.117, 1.05
No. of reflections3377
No. of parameters192
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.20, 0.21

Computer programs: CrysAlis PRO (Agilent, 2011), SIR92 (Altomare et al., 1993), SHELXL97 (Sheldrick, 2008), XP (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top
CgA denotes the centroid of the phenyl ring C1 - C6
D—H···AD—HH···AD···AD—H···A
C5—H5···O22i0.932.803.704 (2)164
C6—H6···O14ii0.932.733.648 (2)172
C16—H16B···O22iii0.962.663.614 (3)171
C27—H27···Cl4iv0.932.883.739 (2)154
C25—H25···CgAv0.932.903.744 (3)151
Symmetry codes: (i) x, y+1, z; (ii) x+2, y+1, z+1; (iii) x+1, y, z; (iv) x+1, y1, z; (v) x+2, y+1, z+2.
 

Acknowledgements

ASD thanks the University of Mysore for research facilities. HSY thanks R. L. Fine Chem, Bengaluru, India, for the gift sample of the title compound.

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