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

Nayak, P.S.; Narayana, B.; Jasinski, J.P.; Yathirajan, H.S.; Sarojini, B.K.

doi:10.1107/S1600536813012531

organic compounds

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ISSN: 2056-9890

Volume 69| Part 6| June 2013| Page o891

doi:10.1107/S1600536813012531

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

Prakash S. Nayak,^a B. Narayana,^a Jerry P. Jasinski,^b ^* H. S. Yathirajan ^c and B. K. Sarojini ^d

^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 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

Crystal data

C₁₂H₁₀BrN₃O
M_r = 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 ) T_min = 0.388, T_max = 1.000
13941 measured reflections
2317 independent reflections
2036 reflections with I > 2σ(I)
R_int = 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
Δρ_max = 0.75 e Å⁻³
Δρ_min = −0.81 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	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); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; 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.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536813012531/bt6905sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536813012531/bt6905Isup2.hkl

Supporting information file. DOI: 10.1107/S1600536813012531/bt6905Isup3.cml

checkCIF report

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).

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

	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.
	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.
	Fig. 3. Reaction scheme.

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

Crystal data top

C₁₂H₁₀BrN₃O	D_x = 1.659 Mg m⁻³
M_r = 292.14	Cu Kα radiation, λ = 1.54184 Å
Orthorhombic, Pbca	Cell parameters from 5193 reflections
a = 10.6804 (4) Å	θ = 4.1–72.4°
b = 7.5196 (3) Å	µ = 4.69 mm⁻¹
c = 29.1355 (10) Å	T = 173 K
V = 2339.94 (14) Å³	Chunk, colorless
Z = 8	0.16 × 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^-1	R_int = 0.036
ω scans	θ_max = 72.6°, θ_min = 5.1°
Absorption correction: multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)	h = −7→13
T_min = 0.388, T_max = 1.000	k = −9→9
13941 measured reflections	l = −35→33
2317 independent reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F² > 2σ(F²)] = 0.035	w = 1/[σ²(F_o²) + (0.0494P)² + 2.0499P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.095	(Δ/σ)_max = 0.001
S = 1.03	Δρ_max = 0.75 e Å⁻³
2317 reflections	Δρ_min = −0.81 e Å⁻³
158 parameters

Crystal data top

C₁₂H₁₀BrN₃O	V = 2339.94 (14) Å³
M_r = 292.14	Z = 8
Orthorhombic, Pbca	Cu Kα radiation
a = 10.6804 (4) Å	µ = 4.69 mm⁻¹
b = 7.5196 (3) Å	T = 173 K
c = 29.1355 (10) Å	0.16 × 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)
T_min = 0.388, T_max = 1.000	R_int = 0.036
13941 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.035	0 restraints
wR(F²) = 0.095	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	Δρ_max = 0.75 e Å⁻³
2317 reflections	Δρ_min = −0.81 e Å⁻³
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

	x	y	z	U_iso*/U_eq
Br1	0.64022 (3)	0.29843 (4)	0.81514 (2)	0.04987 (14)
O1	0.77445 (16)	0.3961 (3)	0.58151 (7)	0.0473 (5)
N1	0.5962 (2)	0.3332 (3)	0.54173 (7)	0.0339 (5)
H1	0.524 (3)	0.340 (4)	0.5413 (10)	0.033 (8)*
N2	0.55700 (18)	0.1871 (3)	0.47422 (8)	0.0357 (5)
N3	0.81075 (18)	0.1345 (3)	0.45762 (7)	0.0351 (5)
C1	0.6614 (2)	0.4063 (4)	0.57735 (9)	0.0346 (5)
C2	0.6436 (2)	0.2438 (4)	0.50359 (9)	0.0315 (5)
C3	0.7716 (2)	0.2175 (3)	0.49533 (9)	0.0332 (5)
H3	0.8300	0.2586	0.5165	0.040*
C4	0.7231 (2)	0.0759 (3)	0.42843 (9)	0.0367 (6)
H4	0.7475	0.0161	0.4019	0.044*
C5	0.5977 (2)	0.1023 (4)	0.43686 (9)	0.0378 (6)
H5	0.5395	0.0597	0.4158	0.045*
C6	0.5806 (2)	0.5067 (4)	0.61136 (9)	0.0374 (6)
H6A	0.5997	0.6326	0.6093	0.045*
H6B	0.4933	0.4910	0.6031	0.045*
C7	0.5995 (2)	0.4464 (3)	0.66018 (9)	0.0315 (5)
C8	0.7040 (2)	0.5003 (3)	0.68536 (8)	0.0326 (5)
H8	0.7653	0.5691	0.6713	0.039*
C9	0.7177 (2)	0.4531 (3)	0.73080 (9)	0.0341 (5)
H9	0.7876	0.4897	0.7473	0.041*
C10	0.6263 (2)	0.3510 (3)	0.75151 (9)	0.0323 (5)
C11	0.5237 (2)	0.2907 (3)	0.72733 (10)	0.0384 (6)
H11	0.4639	0.2191	0.7414	0.046*
C12	0.5116 (2)	0.3387 (4)	0.68182 (10)	0.0389 (6)
H12	0.4430	0.2980	0.6652	0.047*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Br1	0.0638 (2)	0.0486 (2)	0.0372 (2)	−0.00515 (14)	0.00523 (12)	0.00487 (12)
O1	0.0237 (9)	0.0708 (14)	0.0474 (11)	0.0046 (9)	−0.0071 (7)	−0.0090 (10)
N1	0.0180 (10)	0.0469 (13)	0.0367 (11)	0.0001 (9)	0.0016 (8)	0.0025 (9)
N2	0.0227 (10)	0.0453 (12)	0.0390 (12)	0.0003 (9)	−0.0018 (8)	0.0025 (9)
N3	0.0256 (10)	0.0398 (12)	0.0398 (11)	0.0027 (9)	0.0021 (8)	0.0073 (9)
C1	0.0286 (12)	0.0399 (14)	0.0355 (13)	0.0008 (10)	−0.0016 (10)	0.0050 (11)
C2	0.0225 (11)	0.0376 (12)	0.0344 (13)	−0.0009 (9)	−0.0017 (9)	0.0088 (10)
C3	0.0229 (11)	0.0410 (14)	0.0356 (12)	−0.0003 (10)	0.0008 (9)	0.0081 (10)
C4	0.0336 (13)	0.0408 (14)	0.0357 (13)	0.0025 (11)	0.0005 (10)	0.0038 (11)
C5	0.0314 (12)	0.0438 (14)	0.0382 (14)	−0.0006 (11)	−0.0045 (10)	0.0026 (11)
C6	0.0274 (12)	0.0422 (14)	0.0428 (14)	0.0065 (11)	−0.0032 (10)	0.0007 (12)
C7	0.0230 (11)	0.0306 (12)	0.0409 (13)	0.0042 (9)	−0.0002 (9)	−0.0021 (10)
C8	0.0258 (11)	0.0306 (12)	0.0413 (13)	−0.0057 (10)	0.0028 (9)	−0.0013 (10)
C9	0.0319 (12)	0.0290 (12)	0.0414 (13)	−0.0045 (10)	−0.0040 (10)	−0.0023 (10)
C10	0.0362 (13)	0.0278 (11)	0.0330 (12)	0.0035 (9)	0.0044 (10)	0.0000 (10)
C11	0.0261 (12)	0.0335 (13)	0.0556 (16)	−0.0048 (10)	0.0068 (11)	0.0036 (11)
C12	0.0246 (12)	0.0392 (14)	0.0529 (16)	−0.0038 (10)	−0.0053 (10)	−0.0013 (12)

Geometric parameters (Å, º) top

Br1—C10	1.901 (3)	C5—H5	0.9300
O1—C1	1.216 (3)	C6—C7	1.507 (4)
N1—C1	1.365 (3)	C6—H6A	0.9700
N1—C2	1.394 (3)	C6—H6B	0.9700
N1—H1	0.78 (3)	C7—C12	1.391 (4)
N2—C2	1.330 (3)	C7—C8	1.396 (3)
N2—C5	1.334 (3)	C8—C9	1.378 (4)
N3—C3	1.331 (3)	C8—H8	0.9300
N3—C4	1.339 (3)	C9—C10	1.381 (3)
C1—C6	1.516 (4)	C9—H9	0.9300
C2—C3	1.402 (3)	C10—C11	1.379 (4)
C3—H3	0.9300	C11—C12	1.380 (4)
C4—C5	1.376 (4)	C11—H11	0.9300
C4—H4	0.9300	C12—H12	0.9300

C1—N1—C2	128.0 (2)	C1—C6—H6A	109.0
C1—N1—H1	120 (2)	C7—C6—H6B	109.0
C2—N1—H1	113 (2)	C1—C6—H6B	109.0
C2—N2—C5	116.8 (2)	H6A—C6—H6B	107.8
C3—N3—C4	117.3 (2)	C12—C7—C8	118.1 (2)
O1—C1—N1	123.8 (3)	C12—C7—C6	120.9 (2)
O1—C1—C6	122.1 (2)	C8—C7—C6	121.1 (2)
N1—C1—C6	114.0 (2)	C9—C8—C7	121.0 (2)
N2—C2—N1	114.5 (2)	C9—C8—H8	119.5
N2—C2—C3	121.5 (2)	C7—C8—H8	119.5
N1—C2—C3	124.0 (2)	C8—C9—C10	119.2 (2)
N3—C3—C2	120.9 (2)	C8—C9—H9	120.4
N3—C3—H3	119.5	C10—C9—H9	120.4
C2—C3—H3	119.5	C11—C10—C9	121.4 (2)
N3—C4—C5	121.3 (2)	C11—C10—Br1	119.5 (2)
N3—C4—H4	119.4	C9—C10—Br1	119.10 (19)
C5—C4—H4	119.4	C10—C11—C12	118.6 (2)
N2—C5—C4	122.1 (2)	C10—C11—H11	120.7
N2—C5—H5	118.9	C12—C11—H11	120.7
C4—C5—H5	118.9	C11—C12—C7	121.6 (2)
C7—C6—C1	113.0 (2)	C11—C12—H12	119.2
C7—C6—H6A	109.0	C7—C12—H12	119.2

C2—N1—C1—O1	−3.2 (4)	N1—C1—C6—C7	127.0 (2)
C2—N1—C1—C6	175.4 (2)	C1—C6—C7—C12	−103.9 (3)
C5—N2—C2—N1	179.3 (2)	C1—C6—C7—C8	77.7 (3)
C5—N2—C2—C3	0.8 (4)	C12—C7—C8—C9	−2.1 (4)
C1—N1—C2—N2	−179.9 (2)	C6—C7—C8—C9	176.4 (2)
C1—N1—C2—C3	−1.4 (4)	C7—C8—C9—C10	0.0 (4)
C4—N3—C3—C2	−0.8 (4)	C8—C9—C10—C11	2.0 (4)
N2—C2—C3—N3	0.0 (4)	C8—C9—C10—Br1	−176.14 (19)
N1—C2—C3—N3	−178.4 (2)	C9—C10—C11—C12	−1.8 (4)
C3—N3—C4—C5	0.8 (4)	Br1—C10—C11—C12	176.3 (2)
C2—N2—C5—C4	−0.8 (4)	C10—C11—C12—C7	−0.4 (4)
N3—C4—C5—N2	0.0 (4)	C8—C7—C12—C11	2.3 (4)
O1—C1—C6—C7	−54.4 (4)	C6—C7—C12—C11	−176.2 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	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−1/2, −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 formula	C₁₂H₁₀BrN₃O
M_r	292.14
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	173
a, b, c (Å)	10.6804 (4), 7.5196 (3), 29.1355 (10)
V (Å³)	2339.94 (14)
Z	8
Radiation type	Cu Kα
µ (mm⁻¹)	4.69
Crystal size (mm)	0.16 × 0.08 × 0.06

Data collection
Diffractometer	Agilent Xcalibur Eos Gemini diffractometer
Absorption correction	Multi-scan (CrysAlis PRO and CrysAlis RED; Agilent, 2012)
T_min, T_max	0.388, 1.000
No. of measured, independent and observed [I > 2σ(I)] reflections	13941, 2317, 2036
R_int	0.036
(sin θ/λ)_max (Å⁻¹)	0.619

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.035, 0.095, 1.03
No. of reflections	2317
No. of parameters	158
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	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···A	D—H	H···A	D···A	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)	122.5
C3—H3···N2ⁱⁱ	0.93	2.47	3.255 (3)	141.7
C6—H6A···O1ⁱⁱⁱ	0.97	2.53	3.424 (4)	153.8

Symmetry codes: (i) x−1/2, −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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