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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 65| Part 10| October 2009| Page o2361
doi:10.1107/S1600536809034813

5-Chloro­acetyl-4-methyl-2,3,4,5-tetra­hydro-1H-1,5-benzodiazepin-2-one

K. Ravichandran,a P. Sakthivel,b S. Ponnuswamy,b P. Ramesha and M. N. Ponnuswamya*

aCentre of Advanced Study in Crystallography and Biophysics, University of Madras, Guindy Campus, Chennai 600 025, India, and bDepartment of Chemistry, Government Arts College (Autonomous), Coimbatore 641 018, India
*Correspondence e-mail: mnpsy2004@yahoo.com

(Received 13 August 2009; accepted 30 August 2009; online 5 September 2009)

In the title compound, C12H13ClN2O2, the benzodiazepine ring adopts a distorted boat conformation. The carbonyl O atom and the Cl atom of the chloro­acetyl group are in a cis conformation. The crystal packing is controlled by inter­molecular C—H⋯O and N—H⋯O inter­actions.

Related literature

For hydrogen-bond motifs, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]). For puckering and asymmetry parameters, see: Cremer & Pople (1975[Cremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354-1358.]); Nardelli (1983[Nardelli, M. (1983). Acta Cryst. C39, 1141-1142.]). For the use of benzodiazepines in the treatment of gastrointestinal and central nervous system disorders, see: Rahbaek et al. (1999[Rahbaek, L., Breinholt, J., Frisvad, J. C. & Christophersen, C. (1999). J. Org. Chem. 64, 1689-1692.]).

[Scheme 1]

Experimental

Crystal data

  • C12H13ClN2O2

  • Mr = 252.69

  • Monoclinic, C 2/c

  • a = 16.7656 (4) Å

  • b = 8.8171 (2) Å

  • c = 17.0125 (4) Å

  • β = 105.803 (1)°

  • V = 2419.80 (10) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.31 mm−1

  • T = 293 K

  • 0.30 × 0.25 × 0.20 mm
Data collection

  • Bruker Kappa APEXII area-detector diffractometer

  • Absorption correction: multi-scan (SADABS; Sheldrick, 2001[Sheldrick, G. M. (2001). SADABS. University of Göttingen, Germany.]) Tmin = 0.912, Tmax = 0.940

  • 17051 measured reflections

  • 4087 independent reflections

  • 2835 reflections with I > 2σ(I)

  • Rint = 0.026
Refinement

  • R[F2 > 2σ(F2)] = 0.043

  • wR(F2) = 0.128

  • S = 1.02

  • 4087 reflections

  • 159 parameters

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

  • Δρmax = 0.30 e Å−3

  • Δρmin = −0.33 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A D⋯A D—H⋯A
C4—H4⋯O2 0.98 2.32 2.6952 (17) 102
N1—H1⋯O1i 0.881 (18) 1.958 (18) 2.8375 (16) 176.4 (16)
C7—H7⋯O2ii 0.93 2.43 3.2818 (17) 153
C14—H14A⋯O1iii 0.97 2.52 3.2411 (18) 131
Symmetry codes: (i) -x+1, -y, -z+1; (ii) [-x+{\script{1\over 2}}, y+{\script{1\over 2}}, -z+{\script{3\over 2}}]; (iii) [x, -y, z+{\script{1\over 2}}].

Data collection: APEX2 (Bruker, 2004[Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2004[Bruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); data reduction: SAINT; 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: ORTEP-3 (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536809034813/bt5035sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809034813/bt5035Isup2.hkl

checkCIF report


Comment top

Benzodiazepines are known for their natural occurrence in filamentous fungi and actinomycetes of the genera pencillium, aspergillus and streptomyces. Benzodiazepines from aspergillus include asperlicin, which is used for treatment of gastrointestinal and central nervous system (CNS) disorders (Rahbaek et al.,1999). In view of these importance and to ascertain the molecular conformation, crystallographic study of the title compound has been carried out.

The ORTEP diagram of the title compound is shown in Fig.1. The benzodiazepine ring adopts a distorted boat conformation. The puckering parameters (Cremer & Pople, 1975) and the asymmetry parameters (Nardelli, 1983) for this ring are q2 = 0.965 (1) Å, q3 = 0.155 (1) Å, ϕ2 = 144.0 (1)°, ϕ3 = 11.4 (5)° and Δ2(C4)=7.8 (1)°. The sum of the bond angles at N1(359.4°) and N5(359.99°) of the benzodiazepine ring is in accrdance with sp2 hybridization. The choloroacetyl group adopts an extended conformation, which is evidenced from the torsion angle N5—C13—C14—Cl1[-161.9 (1)°].

The crystal packing is controlled by C—H···O and N—H···O types of intra and intermolecular interactions in addition to van der Waals forces. Atom N1 at (x, y, z) donates a proton to O1 (-x + 1, -y, -z + 1), which forms a graph set motif of R22(8) dimer (Bernstein et al., 1995). The intermolecular hydrogen bond C14—H14A···O1 connect the dimers into a C9 one dimensional chain running along c–axis as shown in Fig 2. Thus the two dimensional network is connected by an intermolecular hydrogen bond C7—H7···O2 which leads to a C6 zig–zag chain running along b–axis.

Related literature top

For hydrogen-bond motifs, see: Bernstein et al. (1995). For puckering and asymmetry parameters, see: Cremer & Pople (1975); Nardelli (1983). For the use of benzodiazepines in the treatment of gastrointestinal and central nervous system disorders, see: Rahbaek et al. (1999).

Experimental top

To a solution of tetrahydro-4-methyl-1,5-benzodiazepin-2-one (0.88 g, 5 mmol) in anhydrous benzene (50 ml) was added triethylamine (2.8 ml, 20 mmol) and chloroacetyl chloride (1.59 ml, 20 mmol). The contents were allowed to reflux on a water bath for 6hrs. The reaction mixture was washed with sodium bicarbonate solution (10%), water and dried. The crude mass was crystallized from ethanol.

Refinement top

The H atom bonded to N was freely refined and the other H atoms were positioned geometrically (C—H=0.93–0.98 Å) and allowed to ride on their parent atoms, with 1.5Ueq(C) for methyl H and 1.2 Ueq(C) for other H atoms.

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT (Bruker, 2004); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. Perspective view of the molecule showing the thermal ellipsoids are drawn at 50% probability level.
[Figure 2] Fig. 2. The crystal packing of the molecules viewed down b–axis. H atoms not involved in hydrogen bonding have been omitted for clarity.
5-Chloroacetyl-4-methyl-2,3,4,5-tetrahydro-1H-1,5-benzodiazepin-2-one top
Crystal data top
C12H13ClN2O2F(000) = 1056
Mr = 252.69Dx = 1.387 Mg m−3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 3025 reflections
a = 16.7656 (4) Åθ = 2.5–31.7°
b = 8.8171 (2) ŵ = 0.31 mm−1
c = 17.0125 (4) ÅT = 293 K
β = 105.803 (1)°Block, colourless
V = 2419.80 (10) Å30.30 × 0.25 × 0.20 mm
Z = 8
Data collection top
Bruker Kappa APEXII area-detector
diffractometer		4087 independent reflections
Radiation source: fine-focus sealed tube2835 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.026
ω and ϕ scansθmax = 31.7°, θmin = 2.5°
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)		h = −24→24
Tmin = 0.912, Tmax = 0.940k = −13→12
17051 measured reflectionsl = −25→23
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)] = 0.043Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.128H atoms treated by a mixture of independent and constrained refinement
S = 1.02 w = 1/[σ2(Fo2) + (0.0588P)2 + 0.9172P]
where P = (Fo2 + 2Fc2)/3
4087 reflections(Δ/σ)max = 0.001
159 parametersΔρmax = 0.30 e Å−3
0 restraintsΔρmin = −0.33 e Å−3
Crystal data top
C12H13ClN2O2V = 2419.80 (10) Å3
Mr = 252.69Z = 8
Monoclinic, C2/cMo Kα radiation
a = 16.7656 (4) ŵ = 0.31 mm−1
b = 8.8171 (2) ÅT = 293 K
c = 17.0125 (4) Å0.30 × 0.25 × 0.20 mm
β = 105.803 (1)°
Data collection top
Bruker Kappa APEXII area-detector
diffractometer		4087 independent reflections
Absorption correction: multi-scan
(SADABS; Sheldrick, 2001)		2835 reflections with I > 2σ(I)
Tmin = 0.912, Tmax = 0.940Rint = 0.026
17051 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0430 restraints
wR(F2) = 0.128H atoms treated by a mixture of independent and constrained refinement
S = 1.02Δρmax = 0.30 e Å−3
4087 reflectionsΔρmin = −0.33 e Å−3
159 parameters
Special details top

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
Cl10.44292 (4)−0.22883 (6)0.84052 (3)0.07928 (19)
O10.40338 (7)−0.08925 (12)0.45164 (6)0.0519 (3)
O20.31233 (7)−0.25824 (11)0.68948 (6)0.0512 (3)
N10.42899 (7)0.08091 (13)0.55371 (7)0.0417 (2)
H10.4810 (11)0.0878 (19)0.5523 (10)0.052 (4)*
C20.37704 (8)−0.00571 (15)0.49681 (7)0.0406 (3)
C30.28614 (8)0.00659 (16)0.48988 (8)0.0422 (3)
H3A0.2551−0.03820.43860.051*
H3B0.27110.11290.48900.051*
C40.26188 (8)−0.07178 (15)0.55987 (8)0.0413 (3)
H40.2691−0.18120.55430.050*
N50.31771 (7)−0.02397 (11)0.63873 (6)0.0373 (2)
C60.34684 (8)0.12893 (13)0.64881 (7)0.0361 (2)
C70.31913 (9)0.22890 (15)0.69873 (8)0.0439 (3)
H70.27900.19820.72380.053*
C80.35122 (10)0.37389 (16)0.71114 (9)0.0497 (3)
H80.33280.44060.74470.060*
C90.41025 (10)0.41982 (16)0.67405 (9)0.0503 (3)
H90.43270.51670.68370.060*
C100.43651 (9)0.32312 (16)0.62248 (9)0.0452 (3)
H100.47630.35520.59730.054*
C110.40373 (7)0.17797 (14)0.60811 (7)0.0364 (2)
C120.17216 (10)−0.0438 (2)0.55670 (11)0.0639 (4)
H12A0.1588−0.09710.60070.096*
H12B0.1373−0.07940.50550.096*
H12C0.16340.06290.56190.096*
C130.33861 (8)−0.12933 (14)0.69903 (7)0.0377 (3)
C140.39552 (10)−0.07538 (17)0.77936 (8)0.0502 (3)
H14A0.3639−0.01650.80850.060*
H14B0.4379−0.01000.76870.060*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cl10.1088 (4)0.0608 (3)0.0534 (3)0.0146 (2)−0.0032 (2)0.00910 (19)
O10.0638 (6)0.0553 (6)0.0420 (5)−0.0034 (5)0.0236 (5)−0.0139 (4)
O20.0711 (7)0.0363 (5)0.0469 (6)−0.0094 (4)0.0173 (5)0.0016 (4)
N10.0455 (6)0.0460 (6)0.0362 (5)−0.0005 (5)0.0157 (4)−0.0071 (4)
C20.0535 (7)0.0411 (6)0.0296 (6)0.0012 (5)0.0157 (5)0.0000 (5)
C30.0510 (7)0.0443 (7)0.0297 (6)0.0010 (5)0.0084 (5)−0.0011 (5)
C40.0514 (7)0.0388 (6)0.0329 (6)−0.0055 (5)0.0101 (5)−0.0041 (5)
N50.0521 (6)0.0314 (5)0.0300 (5)−0.0039 (4)0.0139 (4)−0.0040 (4)
C60.0473 (6)0.0300 (5)0.0317 (5)0.0003 (4)0.0121 (5)−0.0033 (4)
C70.0547 (7)0.0401 (7)0.0403 (7)0.0036 (5)0.0189 (6)−0.0069 (5)
C80.0658 (9)0.0368 (7)0.0450 (7)0.0071 (6)0.0123 (6)−0.0112 (5)
C90.0611 (8)0.0322 (6)0.0517 (8)−0.0038 (6)0.0050 (6)−0.0069 (6)
C100.0495 (7)0.0398 (7)0.0459 (7)−0.0057 (5)0.0122 (6)−0.0007 (5)
C110.0430 (6)0.0339 (6)0.0315 (5)0.0020 (5)0.0090 (5)−0.0024 (4)
C120.0541 (9)0.0832 (12)0.0549 (9)−0.0114 (8)0.0160 (7)0.0011 (8)
C130.0491 (6)0.0354 (6)0.0335 (6)−0.0010 (5)0.0195 (5)−0.0014 (4)
C140.0695 (9)0.0445 (7)0.0346 (6)−0.0015 (6)0.0108 (6)0.0016 (5)
Geometric parameters (Å, º) top
Cl1—C141.7591 (15)C6—C111.3913 (17)
O1—C21.2299 (15)C7—C81.3808 (19)
O2—C131.2138 (15)C7—H70.9300
N1—C21.3490 (17)C8—C91.372 (2)
N1—C111.4077 (15)C8—H80.9300
N1—H10.881 (18)C9—C101.379 (2)
C2—C31.5002 (19)C9—H90.9300
C3—C41.5247 (18)C10—C111.3880 (18)
C3—H3A0.9700C10—H100.9300
C3—H3B0.9700C12—H12A0.9600
C4—N51.4730 (16)C12—H12B0.9600
C4—C121.511 (2)C12—H12C0.9600
C4—H40.9800C13—C141.5147 (19)
N5—C131.3573 (16)C14—H14A0.9700
N5—C61.4283 (15)C14—H14B0.9700
C6—C71.3888 (16)
C2—N1—C11124.40 (11)C9—C8—C7120.19 (13)
C2—N1—H1118.0 (11)C9—C8—H8119.9
C11—N1—H1116.9 (11)C7—C8—H8119.9
O1—C2—N1121.06 (12)C8—C9—C10120.36 (13)
O1—C2—C3121.61 (12)C8—C9—H9119.8
N1—C2—C3117.32 (11)C10—C9—H9119.8
C2—C3—C4112.78 (11)C9—C10—C11120.17 (13)
C2—C3—H3A109.0C9—C10—H10119.9
C4—C3—H3A109.0C11—C10—H10119.9
C2—C3—H3B109.0C10—C11—C6119.41 (11)
C4—C3—H3B109.0C10—C11—N1120.05 (12)
H3A—C3—H3B107.8C6—C11—N1120.53 (11)
N5—C4—C12111.43 (11)C4—C12—H12A109.5
N5—C4—C3110.07 (10)C4—C12—H12B109.5
C12—C4—C3111.88 (12)H12A—C12—H12B109.5
N5—C4—H4107.8C4—C12—H12C109.5
C12—C4—H4107.8H12A—C12—H12C109.5
C3—C4—H4107.8H12B—C12—H12C109.5
C13—N5—C6123.09 (10)O2—C13—N5122.02 (12)
C13—N5—C4117.50 (10)O2—C13—C14122.09 (12)
C6—N5—C4119.42 (10)N5—C13—C14115.88 (11)
C7—C6—C11119.74 (11)C13—C14—Cl1111.36 (10)
C7—C6—N5120.80 (11)C13—C14—H14A109.4
C11—C6—N5119.46 (10)Cl1—C14—H14A109.4
C8—C7—C6119.98 (13)C13—C14—H14B109.4
C8—C7—H7120.0Cl1—C14—H14B109.4
C6—C7—H7120.0H14A—C14—H14B108.0
C11—N1—C2—O1−179.31 (12)C7—C8—C9—C101.7 (2)
C11—N1—C2—C31.92 (19)C8—C9—C10—C11−0.4 (2)
O1—C2—C3—C4107.11 (14)C9—C10—C11—C6−2.7 (2)
N1—C2—C3—C4−74.12 (15)C9—C10—C11—N1178.28 (13)
C2—C3—C4—N549.39 (14)C7—C6—C11—C104.55 (19)
C2—C3—C4—C12173.86 (12)N5—C6—C11—C10−175.39 (12)
C12—C4—N5—C1391.37 (15)C7—C6—C11—N1−176.42 (12)
C3—C4—N5—C13−143.90 (11)N5—C6—C11—N13.64 (18)
C12—C4—N5—C6−88.25 (14)C2—N1—C11—C10−135.90 (14)
C3—C4—N5—C636.49 (15)C2—N1—C11—C645.08 (18)
C13—N5—C6—C7−69.95 (17)C6—N5—C13—O2179.08 (12)
C4—N5—C6—C7109.65 (14)C4—N5—C13—O2−0.52 (18)
C13—N5—C6—C11110.00 (14)C6—N5—C13—C140.10 (18)
C4—N5—C6—C11−70.41 (16)C4—N5—C13—C14−179.51 (11)
C11—C6—C7—C8−3.4 (2)O2—C13—C14—Cl119.10 (18)
N5—C6—C7—C8176.59 (13)N5—C13—C14—Cl1−161.92 (10)
C6—C7—C8—C90.2 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4···O20.982.322.6952 (17)102
N1—H1···O1i0.881 (18)1.958 (18)2.8375 (16)176.4 (16)
C7—H7···O2ii0.932.433.2818 (17)153
C14—H14A···O1iii0.972.523.2411 (18)131
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1/2, y+1/2, −z+3/2; (iii) x, −y, z+1/2.

Experimental details

Crystal data
Chemical formulaC12H13ClN2O2
Mr252.69
Crystal system, space groupMonoclinic, C2/c
Temperature (K)293
a, b, c (Å)16.7656 (4), 8.8171 (2), 17.0125 (4)
β (°) 105.803 (1)
V (Å3)2419.80 (10)
Z8
Radiation typeMo Kα
µ (mm−1)0.31
Crystal size (mm)0.30 × 0.25 × 0.20
Data collection
DiffractometerBruker Kappa APEXII area-detector
diffractometer
Absorption correctionMulti-scan
(SADABS; Sheldrick, 2001)
Tmin, Tmax0.912, 0.940
No. of measured, independent and
observed [I > 2σ(I)] reflections		17051, 4087, 2835
Rint0.026
(sin θ/λ)max (Å−1)0.740
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.043, 0.128, 1.02
No. of reflections4087
No. of parameters159
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å−3)0.30, −0.33

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SHELXS97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C4—H4···O20.982.322.6952 (17)101.9
N1—H1···O1i0.881 (18)1.958 (18)2.8375 (16)176.4 (16)
C7—H7···O2ii0.932.433.2818 (17)152.5
C14—H14A···O1iii0.972.523.2411 (18)130.9
Symmetry codes: (i) −x+1, −y, −z+1; (ii) −x+1/2, y+1/2, −z+3/2; (iii) x, −y, z+1/2.
 

Acknowledgements

KR thanks Dr Babu Varghese, SAIF, IIT-Madras, India, for his help with the data collection and the management of Kandaswami Kandar's College, Velur, Namakkal, India, for their encouragement to pursue the programme.

References

First citationBernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555–1573.  CrossRef CAS Web of Science Google Scholar
 First citationBruker (2004). APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.  Google Scholar
 First citationCremer, D. & Pople, J. A. (1975). J. Am. Chem. Soc. 97, 1354–1358.  CrossRef CAS Web of Science Google Scholar
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ISSN: 2056-9890
Volume 65| Part 10| October 2009| Page o2361
doi:10.1107/S1600536809034813
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