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ISSN: 2056-9890

4-[2-(Benzyl­sulfan­yl)acet­yl]-3,4-di­hydro­quinoxalin-2(1H)-one

aInstitute of Chemistry, University of the Punjab, Lahore, Pakistan, and bDepartment of Chemistry, GC University, Lahore 54000, Pakistan
*Correspondence e-mail: munawaralimunawar@yahoo.com

(Received 8 February 2011; accepted 3 March 2011; online 12 March 2011)

In the title compound, C17H16N2O2S, the pyrazinone ring is non-planar (r.m.s. deviation = 0.1595 Å), with maximum deviations for the 4-position N atom and the adjacent non-fused-ring C atom of 0.2557 (15) and −0.2118 (16) Å, respectively. The dihedral angle between the benzyl ring and pyrazinone rings is 30.45 (18)°. Inter­molecular N—H⋯O hydrogen-bonding inter­actions forms inversion dimers which lead to eight-membered R22(8) ring motifs. The dimers are further connected by C—H⋯O inter­actions.

Related literature

For the biological activity of quinoxalines, see: Ali et al. (2000[Ali, A. A., Ismail, M. M. F., El-Gaby, M. S. A., Zahran, M. A. & Ammar, Y. A. (2000). Molecules, 5, 864-873.]); Moustafa & Yameda (2001[Moustafa, O. S. & Yameda, Y. (2001). J. Heterocycl. Chem. 38, 809-811.]). For related structures see: Nasir et al. (2009)[Nasir, W., Munawar, M. A., Ahmad, S., Nadeem, S. & Shahid, M. (2009). Acta Cryst. E65, o3006.]. For graph-set notation, see: Bernstein et al. (1995[Bernstein, J., Davis, R. E., Shimoni, L. & Chang, N.-L. (1995). Angew. Chem. Int. Ed. Engl. 34, 1555-1573.]).

[Scheme 1]

Experimental

Crystal data
  • C17H16N2O2S

  • Mr = 312.38

  • Orthorhombic, P c c n

  • a = 13.9502 (8) Å

  • b = 32.2588 (17) Å

  • c = 6.9728 (3) Å

  • V = 3137.9 (3) Å3

  • Z = 8

  • Mo Kα radiation

  • μ = 0.22 mm−1

  • T = 296 K

  • 0.47 × 0.23 × 0.07 mm

Data collection
  • Bruker Kappa APEXII CCD diffractometer

  • Absorption correction: multi-scan (SADABS; Bruker, 2007[Bruker (2007). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]) Tmin = 0.906, Tmax = 0.985

  • 16363 measured reflections

  • 3892 independent reflections

  • 2412 reflections with I > 2σ(I)

  • Rint = 0.044

Refinement
  • R[F2 > 2σ(F2)] = 0.055

  • wR(F2) = 0.183

  • S = 1.00

  • 3889 reflections

  • 203 parameters

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

  • Δρmax = 0.27 e Å−3

  • Δρmin = −0.20 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
C5—H5⋯O4i 0.93 2.60 3.452 (3) 153
C10—H10B⋯O4i 0.97 2.45 3.202 (3) 134
N2—H1N⋯O3ii 0.85 (3) 2.02 (3) 2.875 (3) 175 (3)
Symmetry codes: (i) [-x+{\script{3\over 2}}, y, z-{\script{1\over 2}}]; (ii) -x+1, -y+1, -z+1.

Data collection: APEX2 (Bruker, 2007[Bruker (2007). SADABS, APEX2 and SAINT. Bruker AXS Inc., Madison, Wisconsin, USA.]); cell refinement: SAINT (Bruker, 2007[Bruker (2007). SADABS, 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 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and PLATON (Spek, 2009[Spek, A. L. (2009). Acta Cryst. D65, 148-155.]); software used to prepare material for publication: WinGX (Farrugia, 1999[Farrugia, L. J. (1999). J. Appl. Cryst. 32, 837-838.]) and PLATON.

Supporting information


Comment top

Annulated pyrazines like quinoxalinones represents an important class of nitrogen containing heterocyclic compounds possessing wide variety of biological and industrial applications. The synthetic and naturally occurring quinoxalines compounds have been reported to show antibacterial (Ali et al., 2000) and antitumor (Moustafa & Yameda, 2001). In the present project we aimed to synthesize novel quinoxalinone derivatives which may have enhanced biological and pharmaceutical application.

The title compound (I) is in continuation of previously published work on the analoguous structure, 4-[(2,5-dimethylanilino)acetyl]-3,4- dihydroquinoxalin-2(1H)-one (II) (Nasir, et al., 2009). The dihedral angle between the aromatic ring (C1/C2/C3/C4/C5/C6) and pyrazinone (C1/C6/N2/C8/C7/N1)is 14.01 (12)°. Unlike (II) no intramolecular hydrogen bonding have been observed in (I). The N—H···O type intermolecular hydrogen bonding developed from the cyclic amido functional group forms the inversion dimers and produce eight membered ring motif R22(8) (Bernstein et al., 1995). Another C—H···O type hydrogen bonding interaction connects these dimers to another molecule Fig. 2. The benzyl ring (C12/C13/C14/C15/C16/C17) is oriented at dihedral angle of 14.01 (12)° and 30.45 (18)° with respect to aromatic and pyrazinone rings.

Related literature top

For the biological activity of quinoxalines, see: Ali et al. (2000); Moustafa & Yameda (2001). For related structures see: Nasir et al. (2009). For graph-set notation, see: Bernstein et al. (1995).

Experimental top

To a suspension of 4-(chloroacetyl)-3,4-dihydroquinoxalin-2(1H)-2-one (2.0 g, 8.9 mmoles) in absolute ethanol (60 mL) fine powdered sodium bicarbonate (1.5 g, 17.8 mmole) was added along with phenylmethanethiol (1.1 mL, 9.0 mmoles). The reaction mixture was heated under reflux for 8-10 h, the progress of the reaction was monitored by TLC (chloroform:ethyl acetate, 7:3 v/v). The reaction mixture was concentrated to half of the original volume under reduced pressure and the precipitate of the product which formed on cooling was filtered, washed with cold ethanol and recrystallized in ethanol.

Refinement top

All the C—H and N—H H-atoms were positioned with idealized geometry with C—H = 0.93 Å for aromatic, with C—H = 0.97 Å for methylene and with N—H = 0.85 (3)Å for amido NH and were refined using a riding model with Uiso(H) = 1.2 Ueq(C & N). The reflection 1 1 0, 1 3 0 and 0 2 0 were omitted in final refinement as these were obscured by the beam stop.

Computing details top

Data collection: APEX2 (Bruker, 2007); cell refinement: SAINT (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009); software used to prepare material for publication: WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Figures top
[Figure 1] Fig. 1. The labelled diagram of structure of (I) with thermal ellipsoids drawn at the 50% probability level.
[Figure 2] Fig. 2. The unit cell packing diagram of (I) showing the hydrogen bondings with dashed lines.
4-[2-(Benzylsulfanyl)acetyl]-3,4-dihydroquinoxalin-2(1H)-one top
Crystal data top
C17H16N2O2SF(000) = 1312
Mr = 312.38Dx = 1.322 Mg m3
Orthorhombic, PccnMo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ab 2acCell parameters from 2915 reflections
a = 13.9502 (8) Åθ = 3.2–23.1°
b = 32.2588 (17) ŵ = 0.22 mm1
c = 6.9728 (3) ÅT = 296 K
V = 3137.9 (3) Å3Plate, colorless
Z = 80.47 × 0.23 × 0.07 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3892 independent reflections
Radiation source: fine-focus sealed tube2412 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.044
ϕ and ω scansθmax = 28.3°, θmin = 1.3°
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
h = 1817
Tmin = 0.906, Tmax = 0.985k = 2343
16363 measured reflectionsl = 99
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)] = 0.055Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.183H atoms treated by a mixture of independent and constrained refinement
S = 1.00 w = 1/[σ2(Fo2) + (0.108P)2 + 0.1052P]
where P = (Fo2 + 2Fc2)/3
3889 reflections(Δ/σ)max = 0.001
203 parametersΔρmax = 0.27 e Å3
0 restraintsΔρmin = 0.20 e Å3
Crystal data top
C17H16N2O2SV = 3137.9 (3) Å3
Mr = 312.38Z = 8
Orthorhombic, PccnMo Kα radiation
a = 13.9502 (8) ŵ = 0.22 mm1
b = 32.2588 (17) ÅT = 296 K
c = 6.9728 (3) Å0.47 × 0.23 × 0.07 mm
Data collection top
Bruker Kappa APEXII CCD
diffractometer
3892 independent reflections
Absorption correction: multi-scan
(SADABS; Bruker, 2007)
2412 reflections with I > 2σ(I)
Tmin = 0.906, Tmax = 0.985Rint = 0.044
16363 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0550 restraints
wR(F2) = 0.183H atoms treated by a mixture of independent and constrained refinement
S = 1.00Δρmax = 0.27 e Å3
3889 reflectionsΔρmin = 0.20 e Å3
203 parameters
Special details top

Geometry. All s.u.'s (except the s.u. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell s.u.'s are taken into account individually in the estimation of s.u.'s in distances, angles and torsion angles; correlations between s.u.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell s.u.'s is used for estimating s.u.'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 > 2σ(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
S10.67947 (5)0.701430 (18)0.13947 (11)0.0539 (3)
O40.77529 (11)0.61610 (5)0.1173 (2)0.0439 (4)
N10.63517 (13)0.58234 (5)0.0968 (3)0.0364 (4)
O30.63199 (12)0.50899 (5)0.4824 (2)0.0530 (5)
C10.47960 (15)0.55216 (6)0.1309 (3)0.0377 (5)
C90.69061 (15)0.61743 (6)0.0743 (3)0.0331 (5)
C80.60499 (16)0.52927 (7)0.3446 (3)0.0399 (5)
C70.67595 (15)0.54813 (7)0.2064 (3)0.0400 (5)
H7A0.73110.55810.27750.048*
H7B0.69800.52690.11840.048*
N20.51165 (14)0.53532 (6)0.3046 (3)0.0442 (5)
C100.64388 (16)0.65674 (7)0.0037 (3)0.0394 (5)
H10A0.57480.65370.01120.047*
H10B0.66070.66100.12990.047*
C50.51272 (19)0.58963 (8)0.1586 (4)0.0490 (6)
H50.55570.60320.23910.059*
C120.50134 (19)0.69134 (8)0.3071 (4)0.0514 (6)
C60.54236 (15)0.57563 (6)0.0199 (3)0.0364 (5)
C30.35632 (19)0.56161 (9)0.1015 (4)0.0581 (7)
H30.29310.55790.14020.070*
C20.38689 (17)0.54535 (7)0.0697 (4)0.0477 (6)
H20.34510.52970.14450.057*
C110.6058 (2)0.69568 (9)0.3512 (4)0.0577 (7)
H11A0.62690.67140.42170.069*
H11B0.61500.71970.43320.069*
C40.4191 (2)0.58341 (8)0.2165 (4)0.0592 (7)
H40.39830.59400.33340.071*
C130.4534 (3)0.65588 (11)0.3446 (5)0.0776 (9)
H130.48530.63390.40250.093*
C160.3583 (3)0.7183 (2)0.1691 (9)0.156 (3)
H160.32670.73960.10540.188*
C140.3569 (3)0.65185 (15)0.2976 (7)0.1123 (16)
H140.32400.62750.32540.135*
C170.4533 (2)0.72278 (13)0.2194 (7)0.1095 (15)
H170.48490.74750.19320.131*
C150.3119 (3)0.6836 (2)0.2115 (7)0.133 (2)
H150.24730.68120.18110.160*
H1N0.471 (2)0.5207 (9)0.367 (4)0.060 (8)*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0418 (4)0.0307 (3)0.0892 (6)0.0038 (2)0.0018 (3)0.0011 (3)
O40.0330 (9)0.0376 (8)0.0611 (10)0.0068 (7)0.0027 (7)0.0045 (7)
N10.0310 (10)0.0358 (10)0.0424 (10)0.0056 (8)0.0005 (8)0.0066 (8)
O30.0451 (10)0.0577 (11)0.0561 (11)0.0119 (8)0.0068 (8)0.0193 (9)
C10.0321 (11)0.0339 (11)0.0473 (13)0.0016 (9)0.0012 (10)0.0006 (10)
C90.0322 (11)0.0316 (10)0.0356 (11)0.0031 (9)0.0043 (9)0.0004 (9)
C80.0380 (12)0.0360 (11)0.0456 (13)0.0075 (10)0.0005 (10)0.0048 (10)
C70.0315 (11)0.0358 (11)0.0527 (13)0.0028 (9)0.0015 (10)0.0092 (10)
N20.0336 (11)0.0494 (11)0.0495 (12)0.0061 (9)0.0057 (9)0.0140 (10)
C100.0355 (12)0.0381 (12)0.0447 (12)0.0009 (10)0.0063 (10)0.0042 (10)
C50.0462 (15)0.0544 (15)0.0464 (14)0.0109 (12)0.0015 (11)0.0093 (11)
C120.0476 (15)0.0572 (15)0.0495 (14)0.0108 (12)0.0027 (11)0.0060 (12)
C60.0302 (11)0.0332 (10)0.0459 (12)0.0037 (9)0.0009 (9)0.0002 (9)
C30.0391 (13)0.0587 (16)0.0765 (19)0.0109 (13)0.0155 (13)0.0009 (14)
C20.0338 (12)0.0452 (13)0.0642 (16)0.0086 (11)0.0019 (11)0.0022 (12)
C110.0540 (17)0.0592 (16)0.0599 (16)0.0099 (13)0.0070 (13)0.0154 (13)
C40.0557 (17)0.0663 (17)0.0558 (16)0.0097 (14)0.0181 (13)0.0063 (13)
C130.068 (2)0.075 (2)0.090 (2)0.0013 (18)0.0167 (18)0.0014 (18)
C160.062 (3)0.211 (6)0.197 (6)0.044 (3)0.011 (3)0.093 (5)
C140.076 (3)0.135 (4)0.126 (4)0.044 (3)0.031 (3)0.041 (3)
C170.053 (2)0.099 (3)0.176 (4)0.028 (2)0.007 (2)0.054 (3)
C150.050 (2)0.241 (7)0.109 (4)0.011 (3)0.010 (2)0.007 (4)
Geometric parameters (Å, º) top
S1—C101.795 (2)C5—H50.9300
S1—C111.808 (3)C12—C131.351 (4)
O4—C91.219 (3)C12—C171.361 (4)
N1—C91.380 (3)C12—C111.496 (4)
N1—C61.418 (3)C3—C21.372 (4)
N1—C71.458 (3)C3—C41.380 (4)
O3—C81.222 (3)C3—H30.9300
C1—C21.380 (3)C2—H20.9300
C1—C61.393 (3)C11—H11A0.9700
C1—N21.400 (3)C11—H11B0.9700
C9—C101.508 (3)C4—H40.9300
C8—N21.346 (3)C13—C141.392 (5)
C8—C71.509 (3)C13—H130.9300
C7—H7A0.9700C16—C151.327 (8)
C7—H7B0.9700C16—C171.379 (6)
N2—H1N0.85 (3)C16—H160.9300
C10—H10A0.9700C14—C151.342 (7)
C10—H10B0.9700C14—H140.9300
C5—C41.382 (4)C17—H170.9300
C5—C61.387 (3)C15—H150.9300
C10—S1—C11101.02 (12)C5—C6—C1119.2 (2)
C9—N1—C6126.45 (18)C5—C6—N1124.2 (2)
C9—N1—C7117.51 (17)C1—C6—N1116.55 (19)
C6—N1—C7116.03 (17)C2—C3—C4120.2 (2)
C2—C1—C6120.3 (2)C2—C3—H3119.9
C2—C1—N2120.3 (2)C4—C3—H3119.9
C6—C1—N2119.4 (2)C3—C2—C1120.0 (2)
O4—C9—N1119.08 (19)C3—C2—H2120.0
O4—C9—C10121.91 (19)C1—C2—H2120.0
N1—C9—C10118.98 (19)C12—C11—S1113.29 (19)
O3—C8—N2122.6 (2)C12—C11—H11A108.9
O3—C8—C7121.0 (2)S1—C11—H11A108.9
N2—C8—C7116.3 (2)C12—C11—H11B108.9
N1—C7—C8112.57 (18)S1—C11—H11B108.9
N1—C7—H7A109.1H11A—C11—H11B107.7
C8—C7—H7A109.1C3—C4—C5120.3 (3)
N1—C7—H7B109.1C3—C4—H4119.9
C8—C7—H7B109.1C5—C4—H4119.9
H7A—C7—H7B107.8C12—C13—C14120.8 (4)
C8—N2—C1123.0 (2)C12—C13—H13119.6
C8—N2—H1N117.0 (19)C14—C13—H13119.6
C1—N2—H1N116.3 (19)C15—C16—C17120.0 (5)
C9—C10—S1112.54 (16)C15—C16—H16120.0
C9—C10—H10A109.1C17—C16—H16120.0
S1—C10—H10A109.1C15—C14—C13119.1 (4)
C9—C10—H10B109.1C15—C14—H14120.4
S1—C10—H10B109.1C13—C14—H14120.4
H10A—C10—H10B107.8C12—C17—C16120.7 (4)
C4—C5—C6119.8 (2)C12—C17—H17119.7
C4—C5—H5120.1C16—C17—H17119.7
C6—C5—H5120.1C16—C15—C14121.1 (4)
C13—C12—C17118.3 (3)C16—C15—H15119.5
C13—C12—C11121.4 (3)C14—C15—H15119.5
C17—C12—C11120.2 (3)
C6—N1—C9—O4166.4 (2)C9—N1—C6—C536.4 (3)
C7—N1—C9—O412.1 (3)C7—N1—C6—C5142.1 (2)
C6—N1—C9—C1015.7 (3)C9—N1—C6—C1145.9 (2)
C7—N1—C9—C10165.86 (19)C7—N1—C6—C135.6 (3)
C9—N1—C7—C8136.4 (2)C4—C3—C2—C12.5 (4)
C6—N1—C7—C844.9 (3)C6—C1—C2—C30.2 (4)
O3—C8—C7—N1159.2 (2)N2—C1—C2—C3179.4 (2)
N2—C8—C7—N122.2 (3)C13—C12—C11—S1114.1 (3)
O3—C8—N2—C1168.6 (2)C17—C12—C11—S162.9 (4)
C7—C8—N2—C110.0 (3)C10—S1—C11—C1254.1 (2)
C2—C1—N2—C8158.4 (2)C2—C3—C4—C51.1 (4)
C6—C1—N2—C821.2 (3)C6—C5—C4—C33.1 (4)
O4—C9—C10—S143.2 (3)C17—C12—C13—C141.1 (5)
N1—C9—C10—S1134.71 (18)C11—C12—C13—C14178.1 (3)
C11—S1—C10—C978.50 (18)C12—C13—C14—C151.0 (6)
C4—C5—C6—C15.8 (4)C13—C12—C17—C160.4 (6)
C4—C5—C6—N1176.6 (2)C11—C12—C17—C16176.6 (4)
C2—C1—C6—C54.4 (3)C15—C16—C17—C122.1 (9)
N2—C1—C6—C5175.2 (2)C17—C16—C15—C142.3 (10)
C2—C1—C6—N1177.8 (2)C13—C14—C15—C160.7 (8)
N2—C1—C6—N12.6 (3)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H5···O4i0.932.603.452 (3)153
C10—H10B···O4i0.972.453.202 (3)134
N2—H1N···O3ii0.85 (3)2.02 (3)2.875 (3)175 (3)
Symmetry codes: (i) x+3/2, y, z1/2; (ii) x+1, y+1, z+1.

Experimental details

Crystal data
Chemical formulaC17H16N2O2S
Mr312.38
Crystal system, space groupOrthorhombic, Pccn
Temperature (K)296
a, b, c (Å)13.9502 (8), 32.2588 (17), 6.9728 (3)
V3)3137.9 (3)
Z8
Radiation typeMo Kα
µ (mm1)0.22
Crystal size (mm)0.47 × 0.23 × 0.07
Data collection
DiffractometerBruker Kappa APEXII CCD
diffractometer
Absorption correctionMulti-scan
(SADABS; Bruker, 2007)
Tmin, Tmax0.906, 0.985
No. of measured, independent and
observed [I > 2σ(I)] reflections
16363, 3892, 2412
Rint0.044
(sin θ/λ)max1)0.667
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.055, 0.183, 1.00
No. of reflections3889
No. of parameters203
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.27, 0.20

Computer programs: APEX2 (Bruker, 2007), SAINT (Bruker, 2007), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and PLATON (Spek, 2009), WinGX (Farrugia, 1999) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C5—H5···O4i0.932.603.452 (3)153
C10—H10B···O4i0.972.453.202 (3)134
N2—H1N···O3ii0.85 (3)2.02 (3)2.875 (3)175 (3)
Symmetry codes: (i) x+3/2, y, z1/2; (ii) x+1, y+1, z+1.
 

Acknowledgements

The authors acknowledge the Higher Education Commission, Pakistan, for providing funding for this research.

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