Crystal structure of 2,5-bis-(4-methyl-pyridin-2-yl)pyrazine chloro-form disolvate.

The heterocyclic molecule in the title solvate, C16H14N4·2CHCl3, possesses inversion symmetry, with the inversion centre situated at the centre of the pyrazine ring. The outer pyridine rings are inclined to the central pyrazine ring by 4.89 (9)°. The compound crystallized as a chloro-form disolvate with the solvent mol-ecules linked to the title mol-ecule by C-H⋯N hydrogen bonds. In the crystal, mol-ecules are further linked by π-π inter-actions involving the pyrazine and pyridine rings of neighbouring mol-ecules [inter-centroid distance = 3.5629 (12) Å; symmetry code: x, y + 1, z + 1].

Related literature

The title compound is the 4-methyl­pyridine derivative of the ligand 2,5-bis­(pyridin-2-yl)pyrazine (bppz), see: Neels & Stoeckli-Evans (1993 ▶); Schmitt (2008 ▶). For the synthesis of a number of transition-metal complexes of bppz, especially of copper(II), and for their magnetic properties, see for example: Escuer et al. (1993 ▶); Neels et al. (1995 ▶); Yuste et al. (2009 ▶); Bentama et al. (2012 ▶).

Experimental

Crystal data

C16H14N4·2CHCl3

M = 501.05

Monoclinic,

a = 16.4498 (17) Å

b = 6.0691 (4) Å

c = 21.605 (3) Å

β = 93.885 (9)°

V = 2152.0 (4) Å3

Z = 4

Mo Kα radiation

μ = 0.81 mm−1

T = 173 K

0.45 × 0.29 × 0.23 mm

Data collection

Stoe IPDS 2 diffractometer

Absorption correction: multi-scan (MULscanABS in PLATON; Spek, 2009 ▶) T min = 0.567, T max = 1.000

9566 measured reflections

1902 independent reflections

1676 reflections with I > 2σ(I)

R int = 0.066

Refinement

R[F 2 > 2σ(F 2)] = 0.040

wR(F 2) = 0.112

S = 1.06

1902 reflections

129 parameters

H-atom parameters constrained

Δρmax = 0.31 e Å−3

Δρmin = −0.30 e Å−3

Data collection: X-AREA (Stoe & Cie, 2009 ▶); cell refinement: X-AREA; data reduction: X-RED32 (Stoe & Cie, 2009 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL2013 (Sheldrick, 2008 ▶); molecular graphics: Mercury (Macrae et al., 2008 ▶); software used to prepare material for publication: SHELXL2013, PLATON (Spek, 2009 ▶) and publCIF (Westrip, 2010 ▶).

Crystal structure: contains datablock(s) I, New_Global_Publ_Block. DOI: 10.1107/S1600536814009544/wm0002sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536814009544/wm0002Isup2.hkl

Click here for additional data file.

. DOI: 10.1107/S1600536814009544/wm0002fig1.tif

A view of the mol­ecular structure of the title compound, with atom labelling [unlabelled atoms are generated by inversion symmetry (symmetry code: −x + 3/2, −y + 3/2, −z + 1/2)]. Displacement ellipsoids are drawn at the 50% probability level. The C—H⋯N hydrogen bonds are shown as dashed lines (see Table 1 for details).

Click here for additional data file.

. DOI: 10.1107/S1600536814009544/wm0002fig2.tif

A view of the crystal packing of the title compound, illustrating the overlap of the pyrazine and pyridine rings of neighbouring mol­ecules.

CCDC reference: 1004308

Additional supporting information: crystallographic information; 3D view; checkCIF report

C16H14N4·2CHCl3	F(000) = 1016
Mr = 501.05	Dx = 1.546 Mg m−3
Monoclinic, I2/a	Mo Kα radiation, λ = 0.71073 Å
a = 16.4498 (17) Å	Cell parameters from 12496 reflections
b = 6.0691 (4) Å	θ = 1.5–25.6°
c = 21.605 (3) Å	µ = 0.81 mm−1
β = 93.885 (9)°	T = 173 K
V = 2152.0 (4) Å3	Rod, colourless
Z = 4	0.45 × 0.29 × 0.23 mm

Stoe IPDS 2 diffractometer	1902 independent reflections
Radiation source: fine-focus sealed tube	1676 reflections with I > 2σ(I)
Plane graphite monochromator	Rint = 0.066
φ + ω scans	θmax = 25.2°, θmin = 1.9°
Absorption correction: multi-scan (MULscanABS in PLATON; Spek, 2009)	h = −19→19
Tmin = 0.567, Tmax = 1.000	k = −7→7
9566 measured reflections	l = −25→25

Refinement on F2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H-atom parameters constrained
R[F2 > 2σ(F2)] = 0.040	w = 1/[σ2(Fo2) + (0.0725P)2 + 0.8241P] where P = (Fo2 + 2Fc2)/3
wR(F2) = 0.112	(Δ/σ)max = 0.002
S = 1.06	Δρmax = 0.31 e Å−3
1902 reflections	Δρmin = −0.30 e Å−3
129 parameters	Extinction correction: SHELXL2013 (Sheldrick, 2008), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
0 restraints	Extinction coefficient: 0.0064 (11)

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

	x	y	z	Uiso*/Ueq
N1	0.72397 (10)	0.6344 (3)	0.19653 (8)	0.0368 (4)
N2	0.89303 (10)	0.2947 (3)	0.25318 (8)	0.0394 (4)
C1	0.68638 (12)	0.8157 (3)	0.21400 (9)	0.0374 (4)
H1	0.6406	0.8677	0.1890	0.045*
C2	0.78878 (11)	0.5676 (3)	0.23260 (8)	0.0328 (4)
C3	0.83238 (11)	0.3674 (3)	0.21341 (9)	0.0328 (4)
C4	0.93307 (13)	0.1154 (3)	0.23585 (10)	0.0418 (5)
H4	0.9771	0.0635	0.2627	0.050*
C5	0.91455 (13)	0.0006 (3)	0.18141 (10)	0.0401 (5)
H5	0.9446	−0.1274	0.1720	0.048*
C6	0.85181 (12)	0.0739 (3)	0.14075 (9)	0.0376 (5)
C7	0.81112 (11)	0.2637 (3)	0.15755 (9)	0.0378 (5)
H7	0.7685	0.3224	0.1305	0.045*
C8	0.82828 (15)	−0.0466 (4)	0.08138 (11)	0.0510 (6)
H8A	0.7910	−0.1672	0.0898	0.077*
H8B	0.8772	−0.1066	0.0642	0.077*
H8C	0.8012	0.0556	0.0515	0.077*
Cl1	0.50499 (4)	0.55130 (10)	0.09961 (3)	0.0569 (2)
Cl2	0.65296 (4)	0.52518 (12)	0.03495 (3)	0.0617 (3)
Cl3	0.57200 (4)	0.12697 (10)	0.06982 (3)	0.0582 (2)
C10	0.59461 (13)	0.4006 (3)	0.09061 (10)	0.0416 (5)
H10	0.6275	0.3999	0.1312	0.050*

	U11	U22	U33	U12	U13	U23
N1	0.0398 (9)	0.0332 (9)	0.0377 (9)	−0.0008 (7)	0.0045 (7)	−0.0041 (7)
N2	0.0429 (9)	0.0351 (9)	0.0405 (9)	0.0005 (7)	0.0053 (7)	−0.0032 (7)
C1	0.0404 (10)	0.0333 (10)	0.0385 (10)	−0.0002 (8)	0.0035 (8)	−0.0027 (8)
C2	0.0356 (10)	0.0294 (10)	0.0340 (10)	−0.0039 (8)	0.0075 (7)	0.0008 (8)
C3	0.0343 (9)	0.0290 (9)	0.0358 (10)	−0.0042 (7)	0.0090 (7)	−0.0001 (7)
C4	0.0467 (11)	0.0374 (11)	0.0417 (11)	0.0052 (9)	0.0054 (8)	−0.0004 (8)
C5	0.0460 (11)	0.0326 (10)	0.0433 (11)	0.0022 (8)	0.0140 (9)	−0.0003 (8)
C6	0.0424 (10)	0.0343 (10)	0.0377 (10)	−0.0038 (8)	0.0136 (8)	−0.0047 (8)
C7	0.0388 (10)	0.0381 (11)	0.0372 (10)	−0.0011 (8)	0.0077 (8)	−0.0025 (8)
C8	0.0578 (13)	0.0499 (13)	0.0460 (12)	0.0046 (10)	0.0076 (10)	−0.0152 (10)
Cl1	0.0557 (4)	0.0538 (4)	0.0613 (4)	0.0130 (3)	0.0040 (3)	−0.0024 (3)
Cl2	0.0589 (4)	0.0759 (5)	0.0507 (4)	−0.0204 (3)	0.0069 (3)	0.0140 (3)
Cl3	0.0758 (5)	0.0417 (4)	0.0594 (4)	−0.0037 (3)	0.0207 (3)	−0.0062 (2)
C10	0.0449 (11)	0.0426 (11)	0.0376 (11)	−0.0012 (9)	0.0041 (8)	0.0024 (9)

N1—C1	1.329 (3)	C5—H5	0.9500
N1—C2	1.340 (3)	C6—C7	1.393 (3)
N2—C4	1.339 (3)	C6—C8	1.504 (3)
N2—C3	1.346 (3)	C7—H7	0.9500
C1—C2i	1.391 (3)	C8—H8A	0.9800
C1—H1	0.9500	C8—H8B	0.9800
C2—C1i	1.391 (3)	C8—H8C	0.9800
C2—C3	1.484 (3)	Cl1—C10	1.757 (2)
C3—C7	1.385 (3)	Cl2—C10	1.760 (2)
C4—C5	1.383 (3)	Cl3—C10	1.753 (2)
C4—H4	0.9500	C10—H10	1.0000
C5—C6	1.383 (3)
C1—N1—C2	116.90 (17)	C5—C6—C8	121.56 (19)
C4—N2—C3	116.44 (17)	C7—C6—C8	121.58 (19)
N1—C1—C2i	122.74 (18)	C3—C7—C6	120.36 (18)
N1—C1—H1	118.6	C3—C7—H7	119.8
C2i—C1—H1	118.6	C6—C7—H7	119.8
N1—C2—C1i	120.36 (17)	C6—C8—H8A	109.5
N1—C2—C3	117.77 (16)	C6—C8—H8B	109.5
C1i—C2—C3	121.87 (17)	H8A—C8—H8B	109.5
N2—C3—C7	122.68 (17)	C6—C8—H8C	109.5
N2—C3—C2	116.19 (16)	H8A—C8—H8C	109.5
C7—C3—C2	121.13 (17)	H8B—C8—H8C	109.5
N2—C4—C5	124.3 (2)	Cl3—C10—Cl1	110.88 (12)
N2—C4—H4	117.9	Cl3—C10—Cl2	110.37 (12)
C5—C4—H4	117.9	Cl1—C10—Cl2	110.64 (12)
C6—C5—C4	119.35 (19)	Cl3—C10—H10	108.3
C6—C5—H5	120.3	Cl1—C10—H10	108.3
C4—C5—H5	120.3	Cl2—C10—H10	108.3
C5—C6—C7	116.86 (18)
C2—N1—C1—C2i	−0.8 (3)	C3—N2—C4—C5	−1.7 (3)
C1—N1—C2—C1i	0.7 (3)	N2—C4—C5—C6	1.2 (3)
C1—N1—C2—C3	−179.12 (16)	C4—C5—C6—C7	0.6 (3)
C4—N2—C3—C7	0.5 (3)	C4—C5—C6—C8	−179.05 (19)
C4—N2—C3—C2	−179.40 (16)	N2—C3—C7—C6	1.2 (3)
N1—C2—C3—N2	−174.82 (17)	C2—C3—C7—C6	−178.94 (16)
C1i—C2—C3—N2	5.3 (3)	C5—C6—C7—C3	−1.7 (3)
N1—C2—C3—C7	5.3 (3)	C8—C6—C7—C3	177.96 (19)
C1i—C2—C3—C7	−174.56 (18)

D—H···A	D—H	H···A	D···A	D—H···A
C10—H10···N1	1.00	2.50	3.335 (3)	141

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C10—H10⋯N1	1.00	2.50	3.335 (3)	141