N-(Pyrazin-2-yl)aniline

The two aromatic rings in the title compound, C₁₀H₉N₃, are inclined at 15.2 (1)° to each other; this opens up the angle at the amino N atom to 130.4 (1)°. The amino N atom forms a hydrogen bond to the 4-N atom of an adjacent mol­ecule to create a chain motif.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.041
• wR factor = 0.101
• Data-to-parameter ratio = 15.9

checkCIF/PLATON results

No syntax errors found



Alert level C
            Value of measurement temperature given =   100.000
            Value of melting point given =     0.000
PLAT153_ALERT_1_C The su's on the Cell Axes   are Equal (x 100000)         30 Ang.

Alert level G
PLAT860_ALERT_3_G Note: Number of Least-Squares Restraints .......          1

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   1 ALERT level C = Check and explain
   1 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   0 ALERT type 2 Indicator that the structure model may be wrong or deficient
   1 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

There are few structural examples of pyrazine compounds having an amino substituent; these are limited to, for example, aminopyrazine (Chao et al., 1976) and pyrazinyl-N-2-nitrophenylaniline (Parsons et al., 2006). In the title compound (Scheme I, Fig. 1), the two aromatic rings are aligned at 15.2 (1)°; these open up the angle at the amino nitrogen to 130.4 (1) °. The amino nitrogen forms a hydrogen bond to the 4-nitrogen atom of an adjacent molecule to furnish a chain motif.

Related literature

For the structure of aminopyrazine, see: Chao et al. (1976). For the structure of 2-pyrazinyl-N-2-nitrophenylaniline; see: Parsons et al. (2006).

S2. Experimental

Chloropyrazine (1 ml, 1.1 mmol) and aniline (1 ml, 1.1 mmol) were heated at 423–433 K for 3 h. The solid was dissolved in water. The compound was extracted with ether. The ether extract was dried over sodium sulfate; evaporation of the solvent gave a colorless crystals among some unidentified dark brown materials.

S3. Refinement

Carbon-bound H-atoms were placed in calculated positions (C—H 0.95 Å) and were included in the refinement in the riding model approximation, with U(H) fixed at 1.2U(C). The amino H-atom was located in a difference Fourier map, and was refined with a distance restraint of N—H 0.88 (1) Å.

Computing details

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: X-SEED (Barbour, 2001); software used to prepare material for publication: publCIF (Westrip, 2008).

Figures

Fig. 1. Thermal ellipsoid plot (Barbour, 2001) of C10H9N3 at the 70% probability level; hydrogen atoms are drawn as spheres of arbitrary radius.

N-(pyrazin-2-yl)aniline

Crystal data

C10H9N3	F(000) = 360
Mr = 171.20	Dx = 1.344 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3723 reflections
a = 11.0644 (3) Å	θ = 3.3–26.4°
b = 7.8423 (3) Å	µ = 0.09 mm^−1
c = 10.8907 (3) Å	T = 100 K
β = 116.439 (2)°	Prism, colourless
V = 846.15 (5) Å^3	0.20 × 0.10 × 0.05 mm
Z = 4

Data collection

Bruker SMART APEX diffractometer	1463 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.033
Graphite monochromator	θmax = 27.5°, θmin = 3.3°
ω scans	h = −14→14
5664 measured reflections	k = −10→10
1934 independent reflections	l = −14→14

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.041	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.101	H atoms treated by a mixture of independent and constrained refinement
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0421P)^2 + 0.247P] where P = (Fo^2 + 2Fc^2)/3
1934 reflections	(Δ/σ)max = 0.001
122 parameters	Δρmax = 0.23 e Å^−3
1 restraint	Δρmin = −0.23 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
N1	0.36080 (11)	0.49391 (15)	0.56127 (12)	0.0188 (3)
H1	0.4485 (9)	0.479 (2)	0.6153 (13)	0.024 (4)*
N2	0.36741 (11)	0.89784 (15)	0.72193 (11)	0.0205 (3)
N3	0.18404 (11)	0.69151 (16)	0.51024 (12)	0.0221 (3)
C1	0.29407 (14)	0.36077 (18)	0.46992 (13)	0.0181 (3)
C2	0.37632 (14)	0.23785 (18)	0.45198 (14)	0.0201 (3)
H2	0.4717	0.2479	0.5007	0.024*
C3	0.32046 (15)	0.1019 (2)	0.36410 (15)	0.0246 (3)
H3	0.3775	0.0188	0.3534	0.029*
C4	0.18124 (15)	0.0862 (2)	0.29138 (15)	0.0255 (3)
H4	0.1427	−0.0058	0.2293	0.031*
C5	0.09930 (14)	0.20604 (19)	0.31037 (14)	0.0235 (3)
H5	0.0040	0.1948	0.2617	0.028*
C6	0.15425 (14)	0.34292 (18)	0.39962 (14)	0.0204 (3)
H6	0.0969	0.4236	0.4125	0.025*
C7	0.31216 (13)	0.64466 (17)	0.58462 (13)	0.0174 (3)
C8	0.40342 (13)	0.74982 (17)	0.69058 (14)	0.0184 (3)
H8	0.4941	0.7127	0.7412	0.022*
C9	0.23812 (14)	0.94629 (19)	0.64641 (14)	0.0232 (3)
H9	0.2078	1.0522	0.6649	0.028*
C10	0.14961 (14)	0.84350 (19)	0.54274 (15)	0.0245 (3)
H10	0.0594	0.8820	0.4914	0.029*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0140 (6)	0.0182 (6)	0.0186 (6)	0.0013 (5)	0.0023 (5)	−0.0019 (5)
N2	0.0201 (6)	0.0197 (6)	0.0210 (6)	−0.0006 (5)	0.0085 (5)	−0.0008 (5)
N3	0.0182 (6)	0.0214 (7)	0.0220 (6)	0.0020 (5)	0.0048 (5)	−0.0008 (5)
C1	0.0201 (7)	0.0171 (7)	0.0147 (6)	−0.0012 (5)	0.0057 (5)	0.0009 (5)
C2	0.0176 (7)	0.0223 (8)	0.0194 (7)	−0.0005 (6)	0.0074 (6)	0.0000 (6)
C3	0.0285 (8)	0.0227 (8)	0.0257 (8)	−0.0008 (6)	0.0150 (6)	−0.0045 (6)
C4	0.0286 (8)	0.0236 (8)	0.0233 (7)	−0.0072 (6)	0.0108 (6)	−0.0075 (6)
C5	0.0197 (7)	0.0251 (8)	0.0214 (7)	−0.0047 (6)	0.0051 (6)	−0.0003 (6)
C6	0.0189 (7)	0.0197 (7)	0.0194 (7)	−0.0005 (6)	0.0056 (6)	0.0008 (6)
C7	0.0180 (7)	0.0175 (7)	0.0164 (7)	−0.0003 (5)	0.0073 (5)	0.0019 (5)
C8	0.0155 (6)	0.0193 (7)	0.0187 (7)	0.0006 (5)	0.0060 (5)	0.0019 (5)
C9	0.0215 (7)	0.0211 (7)	0.0250 (7)	0.0039 (6)	0.0087 (6)	−0.0015 (6)
C10	0.0191 (7)	0.0237 (8)	0.0266 (8)	0.0058 (6)	0.0065 (6)	−0.0001 (6)

Geometric parameters (Å, º)

N1—C7	1.3689 (17)	C3—H3	0.9500
N1—C1	1.4039 (17)	C4—C5	1.384 (2)
N1—H1	0.891 (9)	C4—H4	0.9500
N2—C8	1.3207 (18)	C5—C6	1.393 (2)
N2—C9	1.3488 (17)	C5—H5	0.9500
N3—C7	1.3335 (17)	C6—H6	0.9500
N3—C10	1.3458 (19)	C7—C8	1.4120 (19)
C1—C6	1.3944 (18)	C8—H8	0.9500
C1—C2	1.3978 (19)	C9—C10	1.378 (2)
C2—C3	1.381 (2)	C9—H9	0.9500
C2—H2	0.9500	C10—H10	0.9500
C3—C4	1.389 (2)
C7—N1—C1	130.38 (12)	C4—C5—H5	119.5
C7—N1—H1	113.3 (10)	C6—C5—H5	119.5
C1—N1—H1	116.3 (10)	C5—C6—C1	119.56 (13)
C8—N2—C9	116.75 (12)	C5—C6—H6	120.2
C7—N3—C10	115.67 (12)	C1—C6—H6	120.2
C6—C1—C2	119.09 (13)	N3—C7—N1	121.64 (12)
C6—C1—N1	124.65 (13)	N3—C7—C8	121.03 (12)
C2—C1—N1	116.25 (12)	N1—C7—C8	117.32 (12)
C3—C2—C1	120.72 (13)	N2—C8—C7	122.44 (12)
C3—C2—H2	119.6	N2—C8—H8	118.8
C1—C2—H2	119.6	C7—C8—H8	118.8
C2—C3—C4	120.26 (14)	N2—C9—C10	120.58 (13)
C2—C3—H3	119.9	N2—C9—H9	119.7
C4—C3—H3	119.9	C10—C9—H9	119.7
C5—C4—C3	119.26 (14)	N3—C10—C9	123.53 (13)
C5—C4—H4	120.4	N3—C10—H10	118.2
C3—C4—H4	120.4	C9—C10—H10	118.2
C4—C5—C6	121.08 (13)
C7—N1—C1—C6	−12.7 (2)	C10—N3—C7—N1	−179.30 (12)
C7—N1—C1—C2	168.41 (13)	C10—N3—C7—C8	0.36 (19)
C6—C1—C2—C3	1.1 (2)	C1—N1—C7—N3	−4.2 (2)
N1—C1—C2—C3	−179.89 (12)	C1—N1—C7—C8	176.09 (13)
C1—C2—C3—C4	0.5 (2)	C9—N2—C8—C7	−0.73 (19)
C2—C3—C4—C5	−1.5 (2)	N3—C7—C8—N2	0.3 (2)
C3—C4—C5—C6	0.9 (2)	N1—C7—C8—N2	−179.99 (12)
C4—C5—C6—C1	0.7 (2)	C8—N2—C9—C10	0.4 (2)
C2—C1—C6—C5	−1.7 (2)	C7—N3—C10—C9	−0.7 (2)
N1—C1—C6—C5	179.40 (13)	N2—C9—C10—N3	0.3 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N2^i	0.89 (1)	2.12 (1)	2.977 (2)	162 (1)

Symmetry code: (i) −x+1, y−1/2, −z+3/2.