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

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ISSN: 2056-9890

2-(4-Bromo­phen­yl)-N-(pyrazin-2-yl)acetamide

aDepartment of Studies in Chemistry, Mangalore University, Mangalagangotri 574 199, India, bDepartment of Chemistry, Keene State College, 229 Main Street, Keene, NH 03435-2001, USA, cDepartment of Studies in Chemistry, University of Mysore, Manasagangotri, Mysore 570 006, India, and dDepartment of Chemistry, P.A. College of Engineering, Nadupadavu, Mangalore 574 153, India
*Correspondence e-mail: jjasinski@keene.edu

(Received 6 May 2013; accepted 7 May 2013; online 15 May 2013)

In the title compound, C12H10BrN3O, the dihedral angle between the mean planes of the 4-bromo­phenyl and pyrazin-2-yl rings is 54.6 (3)°. An intra­molecular C—H⋯O hydrogen bond generates an S(6) graph-set motif. In the crystal, weak N—H⋯N hydrogen bonds link the mol­ecules into chains along [100]. The chains are linked via C—H⋯N and C—H⋯O hydrogen bonds, forming two-dimensional networks lying parallel to the ab plane.

Related literature

For the structural similarity of N-substituted 2-aryl­acetamides to the lateral chain of natural benzyl­penicillin, see: Mijin & Marinkovic (2006[Mijin, D. & Marinkovic, A. (2006). Synth. Commun. 36, 193-198.]); Mijin et al. (2008[Mijin, D. Z., Prascevic, M. & Petrovic, S. D. (2008). J. Serb. Chem. Soc. 73, 945-950.]). For the coordination abilities of amides, see: Wu et al. (2008[Wu, W.-N., Cheng, F.-X., Yan, L. & Tang, N. (2008). J. Coord. Chem. 61, 2207-2215.], 2010[Wu, W.-N., Wang, Y., Zhang, A.-Y., Zhao, R.-Q. & Wang, Q.-F. (2010). Acta Cryst. E66, m288.]). For related structures, see: Fun et al. (2012a[Fun, H.-K., Ooi, C. W., Nayak, P. S., Narayana, B. & Sarojini, B. K. (2012a). Acta Cryst. E68, o1349-o1350.],b[Fun, H.-K., Ooi, C. W., Nayak, P. S., Narayana, B. & Sarojini, B. K. (2012b). Acta Cryst. E68, o2526.],c[Fun, H.-K., Shahani, T., Nayak, P. S., Narayana, B. & Sarojini, B. K. (2012c). Acta Cryst. E68, o519.],d[Fun, H.-K., Quah, C. K., Nayak, P. S., Narayana, B. & Sarojini, B. K. (2012d). Acta Cryst. E68, o2558.]). For bond-length data, see: Allen et al. (1987[Allen, F. H., Kennard, O., Watson, D. G., Brammer, L., Orpen, A. G. & Taylor, R. (1987). J. Chem. Soc. Perkin Trans. 2, pp. S1-19.]).

[Scheme 1]

Experimental

Crystal data
  • C12H10BrN3O

  • Mr = 292.14

  • Orthorhombic, P b c a

  • a = 10.6804 (4) Å

  • b = 7.5196 (3) Å

  • c = 29.1355 (10) Å

  • V = 2339.94 (14) Å3

  • Z = 8

  • Cu Kα radiation

  • μ = 4.69 mm−1

  • T = 173 K

  • 0.16 × 0.08 × 0.06 mm

Data collection
  • Agilent Xcalibur Eos Gemini diffractometer

  • Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012[Agilent (2012). CrysAlis PRO and CrysAlis RED. Agilent Technologies, Yarnton, England.]) Tmin = 0.388, Tmax = 1.000

  • 13941 measured reflections

  • 2317 independent reflections

  • 2036 reflections with I > 2σ(I)

  • Rint = 0.036

Refinement
  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 0.095

  • S = 1.03

  • 2317 reflections

  • 158 parameters

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

  • Δρmax = 0.75 e Å−3

  • Δρmin = −0.81 e Å−3

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A D—H H⋯A DA D—H⋯A
N1—H1⋯N3i 0.78 (3) 2.28 (3) 3.059 (3) 178 (3)
C3—H3⋯O1 0.93 2.24 2.848 (3) 123
C3—H3⋯N2ii 0.93 2.47 3.255 (3) 142
C6—H6A⋯O1iii 0.97 2.53 3.424 (4) 154
Symmetry codes: (i) [x-{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]; (ii) [x+{\script{1\over 2}}, -y+{\script{1\over 2}}, -z+1]; (iii) [-x+{\script{3\over 2}}, y+{\script{1\over 2}}, z].

Data collection: CrysAlis PRO (Agilent, 2012[Agilent (2012). CrysAlis PRO and CrysAlis RED. Agilent Technologies, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: OLEX2 (Dolomanov et al., 2009[Dolomanov, O. V., Bourhis, L. J., Gildea, R. J., Howard, J. A. K. & Puschmann, H. (2009). J. Appl. Cryst. 42, 339-341.]); software used to prepare material for publication: OLEX2.

Supporting information


Comment top

N-Substituted 2-arylacetamides are very interesting compounds because of their structural similarity to the lateral chain of natural benzylpenicillin (Mijin et al., 2006, 2008). Amides are also used as ligands due to their excellent coordination abilities (Wu et al., 2008, 2010). Crystal structures of some acetamide derivatives viz., N-(3,4-difluoro phenyl)-2,2-diphenylacetamide, 2-(4-bromophenyl)-N-(5-methylpyridin-2-yl)acetamide, N-(4-bromophenyl)-2-(4-chlorophenyl)acetamide, 2-(4-bromophenyl)-N-(3-chloro-4-fluorophenyl)acetamide, (Fun et al., 2012a,b,c,d) have been reported. In view of the importance of amides, we report herein the crystal structure of the title compound, C12H10BrN3O, (I).

In (I) the dihedral angle between the mean planes of the 4-Bromophenyl and pyrazine rings is 54.6 (3)° (Fig. 1). An intramolecular C—H···O hydrogen bond generates an S(6) graph-set motif. Bond lengths are in normal ranges (Allen et al., 1987). In the crystal, weak N—H···N hydrogen bonds link the molecules into chains along [100]. The chains are linked via weak C—H···N and C—H···O intermolecular interactions, forming two-dimensional networks lying parallel to the ab plane.

Related literature top

For the structural similarity of N-substituted 2-arylacetamides to the lateral chain of natural benzylpenicillin, see: Mijin & Marinkovic (2006); Mijin et al. (2008). For the coordination abilities of amides, see: Wu et al. (2008, 2010). For related structures, see: Fun et al. (2012a,b,c,d). For bond-length data, see: Allen et al. (1987).

Experimental top

4-Bromophenylacetic acid (0.213 g, 1 mmol), 2-aminopyrazine (0.095 g, 1 mmol) and 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (1.0 g, 0.01 mol) were dissolved in dichloromethane (20 mL) (Fig. 3). The mixture was stirred in presence of triethylamine at 273 K for about 3 h. The contents were poured into 100 ml of ice-cold aqueous hydrochloric acid with stirring, which was extracted thrice with dichloromethane. The organic layer was washed with saturated NaHCO3 solution and brine solution, dried and concentrated under reduced pressure to give the title compound (I). Single crystals were grown from methylene chloride by the slow evaporation method (M.P.: 433–435 K).

Refinement top

All of the H atoms were placed in their calculated positions and then refined using the riding model with Atom—H lengths of 0.93Å (CH) or 0.97Å (CH2). Isotropic displacement parameters for these atoms were set to 1.2 (CH, CH2) times Ueq of the parent atom.

Computing details top

Data collection: CrysAlis PRO (Agilent, 2012); cell refinement: CrysAlis PRO (Agilent, 2012); data reduction: CrysAlis PRO (Agilent, 2012); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2012 (Sheldrick, 2008); molecular graphics: OLEX2 (Dolomanov et al., 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

Figures top
[Figure 1] Fig. 1. Molecular structure of the title compound showing the atom labeling scheme and 30% probability displacement ellipsoids. Dashed line indicates an intramolecular C3—H2···O1 hydrogen bond in an S(6) graph-set motif.
[Figure 2] Fig. 2. Packing diagram of the title compound viewed along the c axis. Dashed lines indicate N—H···N hydrogen bonds and weak C—H···N and C—H···O intermolecular interactions linking the molecules into chains along [100] forming 2-D networks lying parallel to the ab plane.
[Figure 3] Fig. 3. Reaction scheme.
2-(4-Bromophenyl)-N-(pyrazin-2-yl)acetamide top
Crystal data top
C12H10BrN3ODx = 1.659 Mg m3
Mr = 292.14Cu Kα radiation, λ = 1.54184 Å
Orthorhombic, PbcaCell parameters from 5193 reflections
a = 10.6804 (4) Åθ = 4.1–72.4°
b = 7.5196 (3) ŵ = 4.69 mm1
c = 29.1355 (10) ÅT = 173 K
V = 2339.94 (14) Å3Chunk, colorless
Z = 80.16 × 0.08 × 0.06 mm
F(000) = 1168
Data collection top
Agilent Xcalibur Eos Gemini
diffractometer
2036 reflections with I > 2σ(I)
Detector resolution: 16.1500 pixels mm-1Rint = 0.036
ω scansθmax = 72.6°, θmin = 5.1°
Absorption correction: multi-scan
(CrysAlis PRO and CrysAlis RED; Agilent, 2012)
h = 713
Tmin = 0.388, Tmax = 1.000k = 99
13941 measured reflectionsl = 3533
2317 independent reflections
Refinement top
Refinement on F20 restraints
Least-squares matrix: fullH atoms treated by a mixture of independent and constrained refinement
R[F2 > 2σ(F2)] = 0.035 w = 1/[σ2(Fo2) + (0.0494P)2 + 2.0499P]
where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.095(Δ/σ)max = 0.001
S = 1.03Δρmax = 0.75 e Å3
2317 reflectionsΔρmin = 0.81 e Å3
158 parameters
Crystal data top
C12H10BrN3OV = 2339.94 (14) Å3
Mr = 292.14Z = 8
Orthorhombic, PbcaCu Kα radiation
a = 10.6804 (4) ŵ = 4.69 mm1
b = 7.5196 (3) ÅT = 173 K
c = 29.1355 (10) Å0.16 × 0.08 × 0.06 mm
Data collection top
Agilent Xcalibur Eos Gemini
diffractometer
2317 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO and CrysAlis RED; Agilent, 2012)
2036 reflections with I > 2σ(I)
Tmin = 0.388, Tmax = 1.000Rint = 0.036
13941 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.095H atoms treated by a mixture of independent and constrained refinement
S = 1.03Δρmax = 0.75 e Å3
2317 reflectionsΔρmin = 0.81 e Å3
158 parameters
Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Br10.64022 (3)0.29843 (4)0.81514 (2)0.04987 (14)
O10.77445 (16)0.3961 (3)0.58151 (7)0.0473 (5)
N10.5962 (2)0.3332 (3)0.54173 (7)0.0339 (5)
H10.524 (3)0.340 (4)0.5413 (10)0.033 (8)*
N20.55700 (18)0.1871 (3)0.47422 (8)0.0357 (5)
N30.81075 (18)0.1345 (3)0.45762 (7)0.0351 (5)
C10.6614 (2)0.4063 (4)0.57735 (9)0.0346 (5)
C20.6436 (2)0.2438 (4)0.50359 (9)0.0315 (5)
C30.7716 (2)0.2175 (3)0.49533 (9)0.0332 (5)
H30.83000.25860.51650.040*
C40.7231 (2)0.0759 (3)0.42843 (9)0.0367 (6)
H40.74750.01610.40190.044*
C50.5977 (2)0.1023 (4)0.43686 (9)0.0378 (6)
H50.53950.05970.41580.045*
C60.5806 (2)0.5067 (4)0.61136 (9)0.0374 (6)
H6A0.59970.63260.60930.045*
H6B0.49330.49100.60310.045*
C70.5995 (2)0.4464 (3)0.66018 (9)0.0315 (5)
C80.7040 (2)0.5003 (3)0.68536 (8)0.0326 (5)
H80.76530.56910.67130.039*
C90.7177 (2)0.4531 (3)0.73080 (9)0.0341 (5)
H90.78760.48970.74730.041*
C100.6263 (2)0.3510 (3)0.75151 (9)0.0323 (5)
C110.5237 (2)0.2907 (3)0.72733 (10)0.0384 (6)
H110.46390.21910.74140.046*
C120.5116 (2)0.3387 (4)0.68182 (10)0.0389 (6)
H120.44300.29800.66520.047*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Br10.0638 (2)0.0486 (2)0.0372 (2)0.00515 (14)0.00523 (12)0.00487 (12)
O10.0237 (9)0.0708 (14)0.0474 (11)0.0046 (9)0.0071 (7)0.0090 (10)
N10.0180 (10)0.0469 (13)0.0367 (11)0.0001 (9)0.0016 (8)0.0025 (9)
N20.0227 (10)0.0453 (12)0.0390 (12)0.0003 (9)0.0018 (8)0.0025 (9)
N30.0256 (10)0.0398 (12)0.0398 (11)0.0027 (9)0.0021 (8)0.0073 (9)
C10.0286 (12)0.0399 (14)0.0355 (13)0.0008 (10)0.0016 (10)0.0050 (11)
C20.0225 (11)0.0376 (12)0.0344 (13)0.0009 (9)0.0017 (9)0.0088 (10)
C30.0229 (11)0.0410 (14)0.0356 (12)0.0003 (10)0.0008 (9)0.0081 (10)
C40.0336 (13)0.0408 (14)0.0357 (13)0.0025 (11)0.0005 (10)0.0038 (11)
C50.0314 (12)0.0438 (14)0.0382 (14)0.0006 (11)0.0045 (10)0.0026 (11)
C60.0274 (12)0.0422 (14)0.0428 (14)0.0065 (11)0.0032 (10)0.0007 (12)
C70.0230 (11)0.0306 (12)0.0409 (13)0.0042 (9)0.0002 (9)0.0021 (10)
C80.0258 (11)0.0306 (12)0.0413 (13)0.0057 (10)0.0028 (9)0.0013 (10)
C90.0319 (12)0.0290 (12)0.0414 (13)0.0045 (10)0.0040 (10)0.0023 (10)
C100.0362 (13)0.0278 (11)0.0330 (12)0.0035 (9)0.0044 (10)0.0000 (10)
C110.0261 (12)0.0335 (13)0.0556 (16)0.0048 (10)0.0068 (11)0.0036 (11)
C120.0246 (12)0.0392 (14)0.0529 (16)0.0038 (10)0.0053 (10)0.0013 (12)
Geometric parameters (Å, º) top
Br1—C101.901 (3)C5—H50.9300
O1—C11.216 (3)C6—C71.507 (4)
N1—C11.365 (3)C6—H6A0.9700
N1—C21.394 (3)C6—H6B0.9700
N1—H10.78 (3)C7—C121.391 (4)
N2—C21.330 (3)C7—C81.396 (3)
N2—C51.334 (3)C8—C91.378 (4)
N3—C31.331 (3)C8—H80.9300
N3—C41.339 (3)C9—C101.381 (3)
C1—C61.516 (4)C9—H90.9300
C2—C31.402 (3)C10—C111.379 (4)
C3—H30.9300C11—C121.380 (4)
C4—C51.376 (4)C11—H110.9300
C4—H40.9300C12—H120.9300
C1—N1—C2128.0 (2)C1—C6—H6A109.0
C1—N1—H1120 (2)C7—C6—H6B109.0
C2—N1—H1113 (2)C1—C6—H6B109.0
C2—N2—C5116.8 (2)H6A—C6—H6B107.8
C3—N3—C4117.3 (2)C12—C7—C8118.1 (2)
O1—C1—N1123.8 (3)C12—C7—C6120.9 (2)
O1—C1—C6122.1 (2)C8—C7—C6121.1 (2)
N1—C1—C6114.0 (2)C9—C8—C7121.0 (2)
N2—C2—N1114.5 (2)C9—C8—H8119.5
N2—C2—C3121.5 (2)C7—C8—H8119.5
N1—C2—C3124.0 (2)C8—C9—C10119.2 (2)
N3—C3—C2120.9 (2)C8—C9—H9120.4
N3—C3—H3119.5C10—C9—H9120.4
C2—C3—H3119.5C11—C10—C9121.4 (2)
N3—C4—C5121.3 (2)C11—C10—Br1119.5 (2)
N3—C4—H4119.4C9—C10—Br1119.10 (19)
C5—C4—H4119.4C10—C11—C12118.6 (2)
N2—C5—C4122.1 (2)C10—C11—H11120.7
N2—C5—H5118.9C12—C11—H11120.7
C4—C5—H5118.9C11—C12—C7121.6 (2)
C7—C6—C1113.0 (2)C11—C12—H12119.2
C7—C6—H6A109.0C7—C12—H12119.2
C2—N1—C1—O13.2 (4)N1—C1—C6—C7127.0 (2)
C2—N1—C1—C6175.4 (2)C1—C6—C7—C12103.9 (3)
C5—N2—C2—N1179.3 (2)C1—C6—C7—C877.7 (3)
C5—N2—C2—C30.8 (4)C12—C7—C8—C92.1 (4)
C1—N1—C2—N2179.9 (2)C6—C7—C8—C9176.4 (2)
C1—N1—C2—C31.4 (4)C7—C8—C9—C100.0 (4)
C4—N3—C3—C20.8 (4)C8—C9—C10—C112.0 (4)
N2—C2—C3—N30.0 (4)C8—C9—C10—Br1176.14 (19)
N1—C2—C3—N3178.4 (2)C9—C10—C11—C121.8 (4)
C3—N3—C4—C50.8 (4)Br1—C10—C11—C12176.3 (2)
C2—N2—C5—C40.8 (4)C10—C11—C12—C70.4 (4)
N3—C4—C5—N20.0 (4)C8—C7—C12—C112.3 (4)
O1—C1—C6—C754.4 (4)C6—C7—C12—C11176.2 (2)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N3i0.78 (3)2.28 (3)3.059 (3)178 (3)
C3—H3···O10.932.242.848 (3)123
C3—H3···N2ii0.932.473.255 (3)142
C6—H6A···O1iii0.972.533.424 (4)154
Symmetry codes: (i) x1/2, y+1/2, z+1; (ii) x+1/2, y+1/2, z+1; (iii) x+3/2, y+1/2, z.

Experimental details

Crystal data
Chemical formulaC12H10BrN3O
Mr292.14
Crystal system, space groupOrthorhombic, Pbca
Temperature (K)173
a, b, c (Å)10.6804 (4), 7.5196 (3), 29.1355 (10)
V3)2339.94 (14)
Z8
Radiation typeCu Kα
µ (mm1)4.69
Crystal size (mm)0.16 × 0.08 × 0.06
Data collection
DiffractometerAgilent Xcalibur Eos Gemini
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO and CrysAlis RED; Agilent, 2012)
Tmin, Tmax0.388, 1.000
No. of measured, independent and
observed [I > 2σ(I)] reflections
13941, 2317, 2036
Rint0.036
(sin θ/λ)max1)0.619
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.095, 1.03
No. of reflections2317
No. of parameters158
H-atom treatmentH atoms treated by a mixture of independent and constrained refinement
Δρmax, Δρmin (e Å3)0.75, 0.81

Computer programs: CrysAlis PRO (Agilent, 2012), SHELXS97 (Sheldrick, 2008), SHELXL2012 (Sheldrick, 2008), OLEX2 (Dolomanov et al., 2009).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N1—H1···N3i0.78 (3)2.28 (3)3.059 (3)178 (3)
C3—H3···O10.932.242.848 (3)122.5
C3—H3···N2ii0.932.473.255 (3)141.7
C6—H6A···O1iii0.972.533.424 (4)153.8
Symmetry codes: (i) x1/2, y+1/2, z+1; (ii) x+1/2, y+1/2, z+1; (iii) x+3/2, y+1/2, z.
 

Acknowledgements

BN thanks the UGC for financial assistance through a BSR one-time grant for the purchase of chemicals. PSN thanks Mangalore University for research facilities and the DST–PURSE for financial assistance. JPJ acknowledges the NSF–MRI program (grant No. CHE-1039027) for funds to purchase the X-ray diffractometer.

References

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