N-tert-Butyl-2-(2,6-di-chloro-phen-yl)imidazo[1,2-a]pyrazin-3-amine.

In the title compound, C16H16Cl2N4, the imidazole ring mean plane makes a dihedral angle of 70.01 (1)° with the phenyl ring. The Cl atoms deviate by -0.0472 (6) and 0.0245 (8) Å from the plane of their attached benzene ring. In the crystal, mol-ecules are linked via pairs of C-H⋯N hydrogen bonds, forming inversion dimers.

Related literature

For applications of the pyrazine ring system in drug development, see: Du et al. (2009 ▶); Dubinina et al. (2006 ▶); Ellsworth et al. (2007 ▶); Mukaiyama et al. (2007 ▶). For background to the fluorescence properties of related compounds, see: Kawai et al. (2001 ▶); Abdullah (2005 ▶). For general background to the use of imidazole derivatives as drugs, see: Dooley et al. (1992 ▶); Jackson et al. (2000 ▶); Banfi et al. (2006 ▶). For related structures, see: Ouzidan et al. (2011 ▶); Nasir et al. (2010 ▶).

Experimental

Crystal data

C16H16Cl2N4

M = 335.23

Triclinic,

a = 8.1482 (4) Å

b = 9.8553 (5) Å

c = 11.5265 (6) Å

α = 93.218 (2)°

β = 99.320 (3)°

γ = 113.026 (2)°

V = 833.31 (7) Å3

Z = 2

Mo Kα radiation

μ = 0.39 mm−1

T = 293 K

0.30 × 0.25 × 0.20 mm

Data collection

Bruker SMART APEXII area-detector diffractometer

Absorption correction: multi-scan (SADABS; Bruker, 2008 ▶) T min = 0.892, T max = 0.926

12583 measured reflections

3438 independent reflections

2941 reflections with I > 2σ(I)

R int = 0.026

Refinement

R[F 2 > 2σ(F 2)] = 0.040

wR(F 2) = 0.120

S = 1.05

3438 reflections

203 parameters

H-atom parameters constrained

Δρmax = 0.34 e Å−3

Δρmin = −0.40 e Å−3

Data collection: APEX2 (Bruker, 2008 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT; 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, 2012 ▶); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ▶).

Click here for additional data file.

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536813013640/su2601sup1.cif

Click here for additional data file.

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813013640/su2601Isup2.hkl

Click here for additional data file.

Supplementary material file. DOI: 10.1107/S1600536813013640/su2601Isup3.cml

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C16H16Cl2N4	Z = 2
Mr = 335.23	F(000) = 348
Triclinic, P1	Dx = 1.336 Mg m−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 8.1482 (4) Å	Cell parameters from 3438 reflections
b = 9.8553 (5) Å	θ = 1.8–26.5°
c = 11.5265 (6) Å	µ = 0.39 mm−1
α = 93.218 (2)°	T = 293 K
β = 99.320 (3)°	Block, colourless
γ = 113.026 (2)°	0.30 × 0.25 × 0.20 mm
V = 833.31 (7) Å3

Bruker SMART APEXII area-detector diffractometer	3438 independent reflections
Radiation source: fine-focus sealed tube	2941 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.026
ω and φ scans	θmax = 26.5°, θmin = 1.8°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −10→10
Tmin = 0.892, Tmax = 0.926	k = −12→12
12583 measured reflections	l = −14→14

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.040	H-atom parameters constrained
wR(F2) = 0.120	w = 1/[σ2(Fo2) + (0.0616P)2 + 0.252P] where P = (Fo2 + 2Fc2)/3
S = 1.05	(Δ/σ)max < 0.001
3438 reflections	Δρmax = 0.34 e Å−3
203 parameters	Δρmin = −0.40 e Å−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.029 (4)

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.

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 > 2sigma(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.

	x	y	z	Uiso*/Ueq
C1	0.8515 (3)	0.3445 (2)	−0.14305 (16)	0.0590 (5)
H1	0.8278	0.3957	−0.2044	0.071*
C2	0.8018 (2)	0.3676 (2)	−0.04035 (15)	0.0490 (4)
H2	0.7462	0.4327	−0.0307	0.059*
C3	0.9215 (2)	0.19622 (19)	0.03479 (14)	0.0428 (4)
C4	0.9674 (3)	0.1803 (2)	−0.07708 (15)	0.0573 (5)
H4	1.0238	0.1165	−0.0894	0.069*
C5	0.8067 (2)	0.29067 (17)	0.16413 (13)	0.0374 (3)
C6	0.8760 (2)	0.19427 (17)	0.21161 (13)	0.0386 (3)
C7	0.8730 (2)	0.15258 (17)	0.33280 (13)	0.0412 (4)
C8	0.9765 (2)	0.25222 (19)	0.43377 (14)	0.0466 (4)
C9	0.9642 (3)	0.2172 (2)	0.54712 (16)	0.0618 (5)
H9	1.0343	0.2872	0.6126	0.074*
C10	0.8473 (4)	0.0779 (3)	0.56200 (17)	0.0737 (6)
H10	0.8378	0.0534	0.6381	0.088*
C11	0.7438 (4)	−0.0259 (2)	0.46540 (18)	0.0711 (6)
H11	0.6652	−0.1206	0.4757	0.085*
C12	0.7582 (3)	0.0125 (2)	0.35278 (16)	0.0543 (4)
C13	0.5310 (2)	0.3227 (2)	0.20642 (16)	0.0529 (4)
C14	0.4269 (3)	0.2237 (5)	0.0930 (3)	0.1323 (15)
H14A	0.4406	0.2817	0.0282	0.198*
H14B	0.3004	0.1768	0.0967	0.198*
H14C	0.4727	0.1489	0.0811	0.198*
C15	0.4854 (5)	0.4564 (4)	0.2163 (4)	0.1293 (15)
H15A	0.5521	0.5183	0.2900	0.194*
H15B	0.3572	0.4243	0.2137	0.194*
H15C	0.5178	0.5118	0.1516	0.194*
C16	0.4855 (4)	0.2406 (4)	0.3101 (3)	0.1010 (10)
H16A	0.5025	0.1498	0.3006	0.151*
H16B	0.3611	0.2180	0.3144	0.151*
H16C	0.5639	0.3012	0.3817	0.151*
N1	0.9338 (2)	0.2515 (2)	−0.16355 (13)	0.0635 (4)
N2	0.9474 (2)	0.13643 (16)	0.13275 (12)	0.0466 (3)
N3	0.83689 (17)	0.29093 (14)	0.04973 (11)	0.0386 (3)
N4	0.72957 (19)	0.38082 (15)	0.20777 (13)	0.0471 (3)
H4A	0.7978	0.4719	0.2361	0.057*
Cl1	1.12956 (7)	0.42849 (6)	0.41790 (4)	0.0670 (2)
Cl2	0.62201 (10)	−0.11935 (6)	0.23322 (5)	0.0897 (3)

	U11	U22	U33	U12	U13	U23
C1	0.0591 (11)	0.0737 (12)	0.0376 (9)	0.0192 (9)	0.0069 (8)	0.0206 (8)
C2	0.0468 (9)	0.0563 (10)	0.0433 (9)	0.0191 (8)	0.0079 (7)	0.0192 (7)
C3	0.0458 (8)	0.0510 (9)	0.0335 (8)	0.0213 (7)	0.0092 (6)	0.0038 (6)
C4	0.0675 (12)	0.0724 (12)	0.0367 (9)	0.0316 (10)	0.0160 (8)	0.0033 (8)
C5	0.0377 (7)	0.0415 (7)	0.0325 (7)	0.0145 (6)	0.0092 (6)	0.0062 (6)
C6	0.0440 (8)	0.0432 (8)	0.0302 (7)	0.0191 (6)	0.0081 (6)	0.0047 (6)
C7	0.0520 (9)	0.0461 (8)	0.0309 (7)	0.0244 (7)	0.0101 (6)	0.0076 (6)
C8	0.0552 (10)	0.0493 (9)	0.0363 (8)	0.0215 (8)	0.0109 (7)	0.0055 (7)
C9	0.0847 (14)	0.0649 (11)	0.0316 (8)	0.0274 (10)	0.0090 (8)	0.0024 (8)
C10	0.1114 (18)	0.0719 (13)	0.0364 (10)	0.0311 (13)	0.0228 (11)	0.0187 (9)
C11	0.1029 (17)	0.0547 (11)	0.0495 (11)	0.0206 (11)	0.0241 (11)	0.0198 (9)
C12	0.0718 (12)	0.0473 (9)	0.0394 (9)	0.0199 (8)	0.0099 (8)	0.0067 (7)
C13	0.0517 (10)	0.0700 (11)	0.0510 (10)	0.0342 (9)	0.0207 (8)	0.0183 (9)
C14	0.0456 (13)	0.225 (4)	0.092 (2)	0.0308 (19)	0.0034 (13)	−0.041 (2)
C15	0.121 (3)	0.123 (3)	0.221 (4)	0.095 (2)	0.105 (3)	0.087 (3)
C16	0.0738 (16)	0.136 (2)	0.113 (2)	0.0448 (17)	0.0477 (16)	0.076 (2)
N1	0.0727 (11)	0.0839 (12)	0.0337 (8)	0.0292 (9)	0.0157 (7)	0.0109 (7)
N2	0.0590 (8)	0.0559 (8)	0.0350 (7)	0.0324 (7)	0.0130 (6)	0.0071 (6)
N3	0.0375 (6)	0.0449 (7)	0.0317 (6)	0.0144 (5)	0.0071 (5)	0.0083 (5)
N4	0.0487 (8)	0.0432 (7)	0.0548 (8)	0.0213 (6)	0.0177 (6)	0.0064 (6)
Cl1	0.0707 (3)	0.0591 (3)	0.0495 (3)	0.0047 (2)	0.0110 (2)	0.0012 (2)
Cl2	0.1200 (5)	0.0537 (3)	0.0557 (3)	−0.0004 (3)	0.0043 (3)	−0.0005 (2)

C1—C2	1.347 (3)	C9—H9	0.9300
C1—N1	1.362 (3)	C10—C11	1.375 (3)
C1—H1	0.9300	C10—H10	0.9300
C2—N3	1.376 (2)	C11—C12	1.383 (3)
C2—H2	0.9300	C11—H11	0.9300
C3—N2	1.327 (2)	C12—Cl2	1.7307 (19)
C3—N3	1.378 (2)	C13—N4	1.487 (2)
C3—C4	1.417 (2)	C13—C14	1.494 (3)
C4—N1	1.304 (3)	C13—C16	1.496 (3)
C4—H4	0.9300	C13—C15	1.506 (3)
C5—C6	1.378 (2)	C14—H14A	0.9600
C5—N3	1.3800 (19)	C14—H14B	0.9600
C5—N4	1.388 (2)	C14—H14C	0.9600
C6—N2	1.3650 (19)	C15—H15A	0.9600
C6—C7	1.479 (2)	C15—H15B	0.9600
C7—C12	1.389 (2)	C15—H15C	0.9600
C7—C8	1.391 (2)	C16—H16A	0.9600
C8—C9	1.379 (2)	C16—H16B	0.9600
C8—Cl1	1.7383 (18)	C16—H16C	0.9600
C9—C10	1.370 (3)	N4—H4A	0.8600
C2—C1—N1	124.75 (17)	C11—C12—Cl2	117.84 (15)
C2—C1—H1	117.6	C7—C12—Cl2	119.48 (13)
N1—C1—H1	117.6	N4—C13—C14	109.91 (16)
C1—C2—N3	117.18 (17)	N4—C13—C16	111.05 (16)
C1—C2—H2	121.4	C14—C13—C16	110.3 (3)
N3—C2—H2	121.4	N4—C13—C15	106.32 (19)
N2—C3—N3	111.51 (13)	C14—C13—C15	110.4 (3)
N2—C3—C4	131.36 (16)	C16—C13—C15	108.7 (2)
N3—C3—C4	117.12 (15)	C13—C14—H14A	109.5
N1—C4—C3	122.75 (18)	C13—C14—H14B	109.5
N1—C4—H4	118.6	H14A—C14—H14B	109.5
C3—C4—H4	118.6	C13—C14—H14C	109.5
C6—C5—N3	104.18 (13)	H14A—C14—H14C	109.5
C6—C5—N4	134.65 (14)	H14B—C14—H14C	109.5
N3—C5—N4	121.10 (13)	C13—C15—H15A	109.5
N2—C6—C5	112.36 (13)	C13—C15—H15B	109.5
N2—C6—C7	122.10 (13)	H15A—C15—H15B	109.5
C5—C6—C7	125.53 (13)	C13—C15—H15C	109.5
C12—C7—C8	115.75 (14)	H15A—C15—H15C	109.5
C12—C7—C6	121.53 (14)	H15B—C15—H15C	109.5
C8—C7—C6	122.64 (14)	C13—C16—H16A	109.5
C9—C8—C7	122.83 (17)	C13—C16—H16B	109.5
C9—C8—Cl1	117.98 (14)	H16A—C16—H16B	109.5
C7—C8—Cl1	119.18 (12)	C13—C16—H16C	109.5
C10—C9—C8	119.10 (18)	H16A—C16—H16C	109.5
C10—C9—H9	120.4	H16B—C16—H16C	109.5
C8—C9—H9	120.4	C4—N1—C1	117.39 (16)
C9—C10—C11	120.58 (18)	C3—N2—C6	104.55 (13)
C9—C10—H10	119.7	C2—N3—C3	120.81 (14)
C11—C10—H10	119.7	C2—N3—C5	131.78 (14)
C10—C11—C12	119.06 (19)	C3—N3—C5	107.39 (12)
C10—C11—H11	120.5	C5—N4—C13	121.18 (14)
C12—C11—H11	120.5	C5—N4—H4A	119.4
C11—C12—C7	122.66 (17)	C13—N4—H4A	119.4
N1—C1—C2—N3	−0.2 (3)	C8—C7—C12—Cl2	179.44 (13)
N2—C3—C4—N1	−178.52 (19)	C6—C7—C12—Cl2	2.7 (2)
N3—C3—C4—N1	0.4 (3)	C3—C4—N1—C1	0.2 (3)
N3—C5—C6—N2	0.31 (18)	C2—C1—N1—C4	−0.3 (3)
N4—C5—C6—N2	−176.49 (17)	N3—C3—N2—C6	0.44 (19)
N3—C5—C6—C7	−178.54 (14)	C4—C3—N2—C6	179.42 (19)
N4—C5—C6—C7	4.7 (3)	C5—C6—N2—C3	−0.46 (19)
N2—C6—C7—C12	−71.1 (2)	C7—C6—N2—C3	178.43 (15)
C5—C6—C7—C12	107.6 (2)	C1—C2—N3—C3	0.8 (2)
N2—C6—C7—C8	112.39 (19)	C1—C2—N3—C5	178.89 (16)
C5—C6—C7—C8	−68.9 (2)	N2—C3—N3—C2	178.22 (14)
C12—C7—C8—C9	−1.6 (3)	C4—C3—N3—C2	−0.9 (2)
C6—C7—C8—C9	175.10 (17)	N2—C3—N3—C5	−0.26 (18)
C12—C7—C8—Cl1	177.99 (13)	C4—C3—N3—C5	−179.40 (15)
C6—C7—C8—Cl1	−5.3 (2)	C6—C5—N3—C2	−178.28 (16)
C7—C8—C9—C10	0.9 (3)	N4—C5—N3—C2	−0.9 (3)
Cl1—C8—C9—C10	−178.66 (18)	C6—C5—N3—C3	−0.03 (16)
C8—C9—C10—C11	0.2 (4)	N4—C5—N3—C3	177.31 (14)
C9—C10—C11—C12	−0.5 (4)	C6—C5—N4—C13	−87.5 (2)
C10—C11—C12—C7	−0.3 (4)	N3—C5—N4—C13	96.14 (18)
C10—C11—C12—Cl2	−178.48 (19)	C14—C13—N4—C5	−40.2 (3)
C8—C7—C12—C11	1.3 (3)	C16—C13—N4—C5	82.2 (2)
C6—C7—C12—C11	−175.48 (19)	C15—C13—N4—C5	−159.7 (2)

D—H···A	D—H	H···A	D···A	D—H···A
C4—H4···N2i	0.93	2.62	3.500 (3)	158

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C4—H4⋯N2i	0.93	2.62	3.500 (3)	158

Symmetry code: (i) .