N,N'-Bis(pyridin-2-yl)benzene-1,4-diamine-quinoxaline (2/1).

The asymmetric unit of the title compound, 2C(16)H(14)N(4)·C(8)H(6)N(2), consits of one mol-ecule of N,N'-bis-(pyridin-2-yl)benzene-1,4-diamine (PDAB) and one half-mol-ecule of quinoxaline (QX) that is located around an inversion centre and disordered over two overlapping positions. The PDAB mol-ecule adopts a non-planar conformation with an E configuration at the two partially double exo C N bonds of the 2-pyridyl-amine units. In the crystal, these self-complementary units are N-H⋯N hydrogen bonded via a cyclic R(2) (2)(8) motif, creating tapes of PDAB mol-ecules extending along [010]. Inversion-related tapes are arranged into pairs through π-π stacking inter-actions between the benzene rings [centroid-centroid distance = 3.818 (1) Å] and the two symmetry-independent pyridine groups [centroid-centroid distance = 3.760 (1) Å]. The QX mol-ecules are enclosed in a cavity formed between six PDAB tapes.

Related literature

For the structures of polymorphic forms of N,N′-di(pyridin-2-yl)benzene-1,4-diamine and its co-crystal with phenazine, see: Bensemann et al. (2002 ▶); Wicher & Gdaniec (2011 ▶); Gdaniec et al. (2005 ▶).

Experimental

Crystal data

2C16H14N4·C8H6N2

M = 654.77

Monoclinic,

a = 11.8285 (9) Å

b = 9.1223 (7) Å

c = 14.7952 (9) Å

β = 93.698 (5)°

V = 1593.1 (2) Å3

Z = 2

Mo Kα radiation

μ = 0.09 mm−1

T = 130 K

0.50 × 0.30 × 0.25 mm

Data collection

Kuma KM-4-CCD κ-geometry diffractometer

8116 measured reflections

2897 independent reflections

2082 reflections with I > 2σ(I)

R int = 0.033

Refinement

R[F 2 > 2σ(F 2)] = 0.045

wR(F 2) = 0.121

S = 0.97

2897 reflections

226 parameters

H-atom parameters constrained

Δρmax = 0.22 e Å−3

Δρmin = −0.28 e Å−3

Data collection: CrysAlis CCD (Oxford Diffraction, 2002 ▶); cell refinement: CrysAlis RED (Oxford Diffraction, 2002 ▶); data reduction: CrysAlis RED; 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, 1997 ▶) and Mercury (Macrae et al., 2006 ▶); software used to prepare material for publication: SHELXL97.

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536811046356/rz2662sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811046356/rz2662Isup2.hkl

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

2C16H14N4·C8H6N2	F(000) = 688
Mr = 654.77	Dx = 1.365 Mg m−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 2533 reflections
a = 11.8285 (9) Å	θ = 4.1–25.0°
b = 9.1223 (7) Å	µ = 0.09 mm−1
c = 14.7952 (9) Å	T = 130 K
β = 93.698 (5)°	Prism, colourless
V = 1593.1 (2) Å3	0.50 × 0.30 × 0.25 mm
Z = 2

Kuma KM-4-CCD κ-geometry diffractometer	2082 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.033
graphite	θmax = 25.4°, θmin = 4.1°
ω scans	h = −13→14
8116 measured reflections	k = −10→9
2897 independent reflections	l = −17→17

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.045	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.121	H-atom parameters constrained
S = 0.97	w = 1/[σ2(Fo2) + (0.0796P)2] where P = (Fo2 + 2Fc2)/3
2897 reflections	(Δ/σ)max < 0.001
226 parameters	Δρmax = 0.22 e Å−3
0 restraints	Δρmin = −0.28 e Å−3

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.

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 > σ(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	Occ. (<1)
N2	0.34420 (10)	0.46004 (13)	0.12792 (9)	0.0251 (3)
N7	0.44563 (11)	0.24793 (13)	0.12278 (9)	0.0291 (3)
H7N	0.5037	0.3082	0.1126	0.035*
N14	0.55190 (10)	−0.35168 (13)	0.12548 (9)	0.0295 (3)
H14N	0.4941	−0.4122	0.1359	0.035*
N16	0.65420 (10)	−0.56243 (13)	0.11839 (9)	0.0260 (3)
C1	0.34338 (12)	0.31287 (16)	0.13482 (10)	0.0232 (4)
C3	0.24879 (13)	0.53106 (17)	0.14294 (10)	0.0282 (4)
H3	0.2492	0.6349	0.1382	0.034*
C4	0.15003 (13)	0.46477 (18)	0.16475 (11)	0.0301 (4)
H4	0.0841	0.5205	0.1745	0.036*
C5	0.15028 (13)	0.31317 (18)	0.17200 (11)	0.0292 (4)
H5	0.0839	0.2630	0.1876	0.035*
C6	0.24654 (13)	0.23600 (17)	0.15651 (10)	0.0266 (4)
H6	0.2474	0.1321	0.1604	0.032*
C8	0.46942 (13)	0.09666 (16)	0.12475 (10)	0.0243 (4)
C9	0.40085 (12)	−0.00484 (17)	0.07789 (10)	0.0264 (4)
H9	0.3335	0.0269	0.0452	0.032*
C10	0.42953 (13)	−0.15119 (16)	0.07830 (10)	0.0256 (4)
H10	0.3813	−0.2195	0.0463	0.031*
C11	0.52812 (13)	−0.20032 (16)	0.12488 (10)	0.0253 (4)
C12	0.59638 (13)	−0.09904 (17)	0.17195 (11)	0.0272 (4)
H12	0.6637	−0.1307	0.2047	0.033*
C13	0.56739 (13)	0.04714 (17)	0.17172 (10)	0.0270 (4)
H13	0.6152	0.1152	0.2042	0.032*
C15	0.65386 (13)	−0.41581 (16)	0.11138 (10)	0.0239 (4)
C17	0.75049 (13)	−0.63284 (18)	0.10303 (11)	0.0302 (4)
H17	0.7507	−0.7367	0.1074	0.036*
C18	0.84841 (14)	−0.56538 (18)	0.08156 (11)	0.0310 (4)
H18	0.9149	−0.6201	0.0719	0.037*
C19	0.84671 (13)	−0.41393 (18)	0.07442 (11)	0.0303 (4)
H19	0.9129	−0.3628	0.0594	0.036*
C20	0.75006 (13)	−0.33812 (17)	0.08900 (10)	0.0276 (4)
H20	0.7482	−0.2343	0.0840	0.033*
C21	0.42626 (15)	0.38226 (19)	0.36086 (12)	0.0393 (5)
H21	0.3839	0.3310	0.3142	0.047*
C22	0.53039 (16)	0.44592 (18)	0.34188 (13)	0.0410 (5)
H22	0.5570	0.4363	0.2829	0.049*
N23	0.59282 (13)	0.51949 (17)	0.40527 (11)	0.0368 (4)	0.50
C23	0.59282 (13)	0.51949 (17)	0.40527 (11)	0.0368 (4)	0.50
H23	0.6629	0.5629	0.3922	0.044*	0.50
C24	0.55231 (12)	0.53158 (16)	0.49075 (11)	0.0275 (4)
C25	0.61465 (13)	0.60804 (16)	0.55764 (11)	0.0357 (4)	0.50
H25	0.6846	0.6529	0.5457	0.043*	0.50
N25	0.61465 (13)	0.60804 (16)	0.55764 (11)	0.0357 (4)	0.50

	U11	U22	U33	U12	U13	U23
N2	0.0240 (7)	0.0225 (7)	0.0290 (7)	0.0005 (5)	0.0025 (6)	−0.0026 (5)
N7	0.0227 (7)	0.0202 (7)	0.0449 (9)	−0.0022 (5)	0.0067 (6)	−0.0004 (6)
N14	0.0224 (7)	0.0208 (7)	0.0457 (9)	−0.0006 (5)	0.0056 (6)	0.0047 (6)
N16	0.0248 (7)	0.0229 (7)	0.0301 (8)	0.0004 (5)	0.0011 (6)	−0.0004 (6)
C1	0.0249 (8)	0.0223 (8)	0.0223 (8)	−0.0012 (6)	0.0010 (6)	−0.0020 (6)
C3	0.0301 (9)	0.0246 (8)	0.0298 (9)	0.0026 (7)	0.0012 (7)	−0.0040 (7)
C4	0.0243 (8)	0.0339 (9)	0.0323 (9)	0.0032 (7)	0.0030 (7)	−0.0048 (7)
C5	0.0247 (8)	0.0361 (9)	0.0270 (9)	−0.0044 (7)	0.0026 (7)	−0.0009 (7)
C6	0.0283 (9)	0.0239 (8)	0.0277 (9)	−0.0022 (7)	0.0019 (7)	0.0000 (6)
C8	0.0238 (8)	0.0212 (8)	0.0284 (9)	−0.0007 (6)	0.0059 (7)	0.0001 (6)
C9	0.0241 (8)	0.0258 (8)	0.0292 (9)	0.0000 (7)	0.0004 (7)	0.0024 (7)
C10	0.0244 (8)	0.0253 (8)	0.0271 (9)	−0.0034 (6)	0.0010 (6)	−0.0015 (6)
C11	0.0257 (8)	0.0219 (8)	0.0289 (9)	0.0009 (6)	0.0056 (7)	0.0024 (6)
C12	0.0231 (8)	0.0299 (9)	0.0283 (9)	0.0019 (7)	0.0003 (7)	0.0026 (7)
C13	0.0248 (8)	0.0277 (9)	0.0288 (9)	−0.0034 (7)	0.0034 (7)	−0.0035 (7)
C15	0.0242 (8)	0.0246 (8)	0.0225 (8)	0.0002 (6)	−0.0007 (6)	0.0002 (6)
C17	0.0298 (9)	0.0267 (8)	0.0336 (9)	0.0037 (7)	−0.0010 (7)	−0.0037 (7)
C18	0.0259 (9)	0.0337 (9)	0.0334 (9)	0.0028 (7)	0.0011 (7)	−0.0068 (7)
C19	0.0231 (9)	0.0374 (10)	0.0302 (9)	−0.0054 (7)	0.0012 (7)	−0.0031 (7)
C20	0.0273 (9)	0.0259 (8)	0.0292 (9)	−0.0028 (7)	−0.0004 (7)	0.0008 (7)
C21	0.0462 (11)	0.0331 (10)	0.0372 (11)	−0.0056 (8)	−0.0086 (9)	0.0026 (8)
C22	0.0550 (12)	0.0324 (10)	0.0362 (10)	0.0004 (9)	0.0081 (9)	0.0027 (8)
N23	0.0364 (9)	0.0337 (9)	0.0411 (10)	−0.0045 (7)	0.0092 (7)	0.0025 (7)
C23	0.0364 (9)	0.0337 (9)	0.0411 (10)	−0.0045 (7)	0.0092 (7)	0.0025 (7)
C24	0.0263 (8)	0.0214 (8)	0.0344 (9)	0.0003 (6)	−0.0005 (7)	0.0021 (7)
C25	0.0314 (8)	0.0331 (9)	0.0417 (10)	−0.0057 (7)	−0.0055 (7)	0.0031 (7)
N25	0.0314 (8)	0.0331 (9)	0.0417 (10)	−0.0057 (7)	−0.0055 (7)	0.0031 (7)

N2—C3	1.3324 (18)	C11—C12	1.385 (2)
N2—C1	1.3465 (19)	C12—C13	1.377 (2)
N7—C1	1.3686 (19)	C12—H12	0.9500
N7—C8	1.4083 (19)	C13—H13	0.9500
N7—H7N	0.9001	C15—C20	1.398 (2)
N14—C15	1.3685 (19)	C17—C18	1.367 (2)
N14—C11	1.4090 (19)	C17—H17	0.9500
N14—H14N	0.9000	C18—C19	1.386 (2)
N16—C17	1.3397 (19)	C18—H18	0.9500
N16—C15	1.3415 (19)	C19—C20	1.365 (2)
C1—C6	1.398 (2)	C19—H19	0.9500
C3—C4	1.372 (2)	C20—H20	0.9500
C3—H3	0.9500	C21—N25i	1.331 (2)
C4—C5	1.387 (2)	C21—C25i	1.331 (2)
C4—H4	0.9500	C21—C22	1.406 (3)
C5—C6	1.370 (2)	C21—H21	0.9499
C5—H5	0.9500	C22—N23	1.336 (2)
C6—H6	0.9500	C22—H22	0.9500
C8—C9	1.387 (2)	N23—C24	1.385 (2)
C8—C13	1.388 (2)	N23—H23	0.9500
C9—C10	1.377 (2)	C24—C25	1.384 (2)
C9—H9	0.9500	C24—C24i	1.408 (3)
C10—C11	1.390 (2)	C25—C21i	1.331 (2)
C10—H10	0.9500	C25—H25	0.9499
C3—N2—C1	117.51 (13)	C11—C12—H12	119.7
C1—N7—C8	126.76 (13)	C12—C13—C8	121.08 (14)
C1—N7—H7N	116.6	C12—C13—H13	119.5
C8—N7—H7N	116.6	C8—C13—H13	119.5
C15—N14—C11	126.54 (13)	N16—C15—N14	114.37 (13)
C15—N14—H14N	116.8	N16—C15—C20	121.68 (14)
C11—N14—H14N	116.7	N14—C15—C20	123.92 (14)
C17—N16—C15	117.59 (14)	N16—C17—C18	124.47 (15)
N2—C1—N7	114.27 (13)	N16—C17—H17	117.8
N2—C1—C6	121.83 (14)	C18—C17—H17	117.8
N7—C1—C6	123.84 (14)	C17—C18—C19	117.27 (15)
N2—C3—C4	124.61 (15)	C17—C18—H18	121.4
N2—C3—H3	117.7	C19—C18—H18	121.4
C4—C3—H3	117.7	C20—C19—C18	120.08 (15)
C3—C4—C5	117.38 (15)	C20—C19—H19	120.0
C3—C4—H4	121.3	C18—C19—H19	120.0
C5—C4—H4	121.3	C19—C20—C15	118.89 (15)
C6—C5—C4	119.79 (15)	C19—C20—H20	120.6
C6—C5—H5	120.1	C15—C20—H20	120.6
C4—C5—H5	120.1	N25i—C21—C22	121.85 (16)
C5—C6—C1	118.86 (15)	C25i—C21—C22	121.85 (16)
C5—C6—H6	120.6	N25i—C21—H21	119.1
C1—C6—H6	120.6	C25i—C21—H21	119.1
C9—C8—C13	118.40 (14)	C22—C21—H21	119.1
C9—C8—N7	122.29 (14)	N23—C22—C21	121.25 (17)
C13—C8—N7	119.25 (13)	N23—C22—H22	119.3
C10—C9—C8	120.60 (14)	C21—C22—H22	119.4
C10—C9—H9	119.7	C22—N23—C24	118.20 (15)
C8—C9—H9	119.7	C22—N23—H23	121.1
C9—C10—C11	120.88 (14)	C24—N23—H23	120.7
C9—C10—H10	119.6	C25—C24—N23	119.55 (14)
C11—C10—H10	119.6	C25—C24—C24i	120.10 (19)
C12—C11—C10	118.52 (14)	N23—C24—C24i	120.34 (18)
C12—C11—N14	122.74 (14)	C21i—C25—C24	118.25 (15)
C10—C11—N14	118.68 (13)	C21i—C25—H25	120.8
C13—C12—C11	120.52 (14)	C24—C25—H25	120.9
C13—C12—H12	119.7
C3—N2—C1—N7	−177.03 (13)	C11—C12—C13—C8	0.1 (2)
C3—N2—C1—C6	0.3 (2)	C9—C8—C13—C12	0.1 (2)
C8—N7—C1—N2	−178.90 (14)	N7—C8—C13—C12	−177.06 (14)
C8—N7—C1—C6	3.9 (2)	C17—N16—C15—N14	178.27 (13)
C1—N2—C3—C4	−0.1 (2)	C17—N16—C15—C20	−0.1 (2)
N2—C3—C4—C5	0.3 (2)	C11—N14—C15—N16	178.07 (14)
C3—C4—C5—C6	−0.7 (2)	C11—N14—C15—C20	−3.6 (2)
C4—C5—C6—C1	0.9 (2)	C15—N16—C17—C18	0.6 (2)
N2—C1—C6—C5	−0.7 (2)	N16—C17—C18—C19	−0.7 (2)
N7—C1—C6—C5	176.37 (14)	C17—C18—C19—C20	0.3 (2)
C1—N7—C8—C9	47.3 (2)	C18—C19—C20—C15	0.2 (2)
C1—N7—C8—C13	−135.63 (16)	N16—C15—C20—C19	−0.3 (2)
C13—C8—C9—C10	0.1 (2)	N14—C15—C20—C19	−178.51 (14)
N7—C8—C9—C10	177.18 (14)	N25i—C21—C22—N23	−0.1 (3)
C8—C9—C10—C11	−0.6 (2)	C25i—C21—C22—N23	−0.1 (3)
C9—C10—C11—C12	0.8 (2)	C21—C22—N23—C24	0.0 (3)
C9—C10—C11—N14	178.09 (14)	C22—N23—C24—C25	−179.52 (15)
C15—N14—C11—C12	−48.1 (2)	C22—N23—C24—C24i	−0.4 (3)
C15—N14—C11—C10	134.72 (16)	N23—C24—C25—C21i	−179.92 (15)
C10—C11—C12—C13	−0.6 (2)	C24i—C24—C25—C21i	1.0 (3)
N14—C11—C12—C13	−177.76 (14)

D—H···A	D—H	H···A	D···A	D—H···A
N14—H14N···N2ii	0.90	2.12	2.9998 (17)	166
N7—H7N···N16iii	0.90	2.13	3.0173 (18)	167

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N14—H14N⋯N2i	0.90	2.12	2.9998 (17)	166
N7—H7N⋯N16ii	0.90	2.13	3.0173 (18)	167

Symmetry codes: (i) ; (ii) .