A third polymorph of N,N'-bis-(pyridin-2-yl)benzene-1,4-diamine.

A third polymorph of the title compound, C(16)H(14)N(4), has been obtained. The 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. Like in the triclinic form [Bensemann et al. (2002 ▶). New J. Chem.26, 448-456], the recognition process between 2-pyridyl-amine units takes place through formation of a cyclic R(2) (2)(8) hydrogen-bond motif, leading to the creation of tapes parallel to [001].

Related literature

For the structures of the ortho­rhom­bic and triclinic polymorphs of N,N′-di(pyridin-2-yl)benzene-1,4-diamine, see: Bensemann et al. (2002 ▶).

Experimental

Crystal data

C16H14N4

M = 262.31

Monoclinic,

a = 7.2534 (2) Å

b = 20.8270 (6) Å

c = 9.0681 (3) Å

β = 106.746 (4)°

V = 1311.79 (7) Å3

Z = 4

Cu Kα radiation

μ = 0.65 mm−1

T = 295 K

0.2 × 0.2 × 0.05 mm

Data collection

Oxford Diffraction SuperNova diffractometer

Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010 ▶) T min = 0.799, T max = 1.000

10413 measured reflections

2398 independent reflections

2221 reflections with I > 2/s(I)

R int = 0.019

Refinement

R[F 2 > 2σ(F 2)] = 0.035

wR(F 2) = 0.094

S = 1.07

2398 reflections

181 parameters

H-atom parameters constrained

Δρmax = 0.11 e Å−3

Δρmin = −0.19 e Å−3

Data collection: CrysAlis PRO (Agilent, 2010 ▶); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR2004 (Burla et al., 2005 ▶); 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/S1600536811044539/rz2657sup1.cif

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536811044539/rz2657Isup2.hkl

Supplementary material file. DOI: 10.1107/S1600536811044539/rz2657Isup3.cml

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

C16H14N4	F(000) = 552
Mr = 262.31	Dx = 1.328 Mg m−3
Monoclinic, P21/c	Melting point: 479 K
Hall symbol: -P 2ybc	Cu Kα radiation, λ = 1.54178 Å
a = 7.2534 (2) Å	Cell parameters from 6262 reflections
b = 20.8270 (6) Å	θ = 2.1–75.8°
c = 9.0681 (3) Å	µ = 0.65 mm−1
β = 106.746 (4)°	T = 295 K
V = 1311.79 (7) Å3	Plate, colourless
Z = 4	0.2 × 0.2 × 0.05 mm

Oxford Diffraction SuperNova diffractometer	2398 independent reflections
Radiation source: Nova Cu X-ray Source	2221 reflections with I > 2/s(I)
mirror	Rint = 0.019
ω scans	θmax = 68.2°, θmin = 6.4°
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2010)	h = −8→8
Tmin = 0.799, Tmax = 1.000	k = −25→25
10413 measured reflections	l = −10→10

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)] = 0.035	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.094	H-atom parameters constrained
S = 1.07	w = 1/[σ2(Fo2) + (0.0478P)2 + 0.2155P] where P = (Fo2 + 2Fc2)/3
2398 reflections	(Δ/σ)max < 0.001
181 parameters	Δρmax = 0.11 e Å−3
0 restraints	Δρmin = −0.19 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
N2	0.18091 (14)	0.15267 (5)	0.53715 (10)	0.0434 (2)
N7	0.34929 (14)	0.13813 (5)	0.36249 (10)	0.0453 (2)
H7N	0.4266	0.1142	0.4380	0.054*
N14	0.53458 (15)	0.12536 (5)	−0.19925 (11)	0.0521 (3)
H14N	0.4314	0.1319	−0.2811	0.063*
N16	0.63876 (14)	0.06275 (5)	−0.36845 (10)	0.0458 (2)
C1	0.18087 (15)	0.15794 (5)	0.38962 (12)	0.0382 (2)
C3	0.02222 (18)	0.17053 (6)	0.57328 (14)	0.0500 (3)
H3	0.0216	0.1663	0.6752	0.060*
C4	−0.13952 (18)	0.19473 (7)	0.46964 (16)	0.0572 (3)
H4	−0.2462	0.2071	0.5000	0.069*
C5	−0.13771 (18)	0.19995 (7)	0.31846 (16)	0.0581 (3)
H5	−0.2449	0.2161	0.2448	0.070*
C6	0.02097 (17)	0.18144 (6)	0.27640 (13)	0.0486 (3)
H6	0.0224	0.1844	0.1744	0.058*
C8	0.39192 (15)	0.13618 (5)	0.22059 (12)	0.0387 (3)
C9	0.34861 (17)	0.18587 (5)	0.11355 (13)	0.0435 (3)
H9	0.2842	0.2220	0.1332	0.052*
C10	0.40017 (17)	0.18215 (6)	−0.02162 (12)	0.0445 (3)
H10	0.3685	0.2157	−0.0920	0.053*
C11	0.49825 (15)	0.12933 (5)	−0.05437 (12)	0.0406 (3)
C12	0.54745 (16)	0.08080 (5)	0.05517 (13)	0.0425 (3)
H12	0.6177	0.0457	0.0380	0.051*
C13	0.49368 (16)	0.08396 (5)	0.18909 (13)	0.0419 (3)
H13	0.5262	0.0505	0.2597	0.050*
C15	0.67958 (16)	0.08914 (5)	−0.22815 (12)	0.0418 (3)
C17	0.7754 (2)	0.02598 (6)	−0.39897 (15)	0.0539 (3)
H17	0.7477	0.0068	−0.4955	0.065*
C18	0.9526 (2)	0.01483 (7)	−0.29741 (16)	0.0603 (4)
H18	1.0408	−0.0122	−0.3228	0.072*
C19	0.99619 (18)	0.04509 (7)	−0.15578 (15)	0.0574 (3)
H19	1.1173	0.0402	−0.0855	0.069*
C20	0.85928 (17)	0.08235 (7)	−0.11991 (14)	0.0506 (3)
H20	0.8858	0.1028	−0.0249	0.061*

	U11	U22	U33	U12	U13	U23
N2	0.0485 (5)	0.0489 (5)	0.0360 (5)	0.0011 (4)	0.0174 (4)	0.0017 (4)
N7	0.0482 (5)	0.0582 (6)	0.0316 (5)	0.0106 (4)	0.0148 (4)	0.0050 (4)
N14	0.0529 (6)	0.0744 (7)	0.0294 (5)	0.0220 (5)	0.0123 (4)	0.0021 (4)
N16	0.0504 (6)	0.0555 (6)	0.0349 (5)	0.0066 (4)	0.0177 (4)	0.0011 (4)
C1	0.0431 (6)	0.0385 (5)	0.0343 (5)	−0.0050 (4)	0.0132 (4)	−0.0027 (4)
C3	0.0539 (7)	0.0573 (7)	0.0456 (6)	−0.0034 (5)	0.0253 (5)	−0.0006 (5)
C4	0.0427 (6)	0.0708 (9)	0.0636 (8)	−0.0016 (6)	0.0242 (6)	−0.0007 (6)
C5	0.0386 (6)	0.0760 (9)	0.0563 (8)	−0.0020 (6)	0.0081 (5)	0.0052 (6)
C6	0.0438 (6)	0.0638 (7)	0.0365 (6)	−0.0053 (5)	0.0090 (5)	−0.0002 (5)
C8	0.0403 (6)	0.0454 (6)	0.0313 (5)	0.0006 (4)	0.0117 (4)	−0.0013 (4)
C9	0.0497 (6)	0.0445 (6)	0.0392 (6)	0.0108 (5)	0.0174 (5)	0.0014 (5)
C10	0.0505 (6)	0.0488 (6)	0.0352 (6)	0.0122 (5)	0.0139 (5)	0.0080 (5)
C11	0.0409 (6)	0.0511 (6)	0.0302 (5)	0.0054 (5)	0.0108 (4)	−0.0014 (4)
C12	0.0465 (6)	0.0415 (6)	0.0411 (6)	0.0078 (5)	0.0150 (5)	−0.0023 (4)
C13	0.0474 (6)	0.0413 (6)	0.0377 (6)	0.0046 (5)	0.0134 (5)	0.0051 (4)
C15	0.0471 (6)	0.0488 (6)	0.0335 (5)	0.0057 (5)	0.0178 (5)	0.0048 (4)
C17	0.0630 (8)	0.0606 (7)	0.0455 (7)	0.0103 (6)	0.0273 (6)	−0.0004 (5)
C18	0.0604 (8)	0.0689 (8)	0.0618 (8)	0.0204 (6)	0.0337 (7)	0.0123 (7)
C19	0.0445 (7)	0.0763 (9)	0.0538 (7)	0.0105 (6)	0.0180 (6)	0.0175 (6)
C20	0.0489 (7)	0.0660 (8)	0.0373 (6)	0.0036 (5)	0.0131 (5)	0.0023 (5)

N2—C3	1.3372 (15)	C8—C13	1.3895 (15)
N2—C1	1.3422 (13)	C8—C9	1.3916 (15)
N7—C1	1.3771 (14)	C9—C10	1.3829 (15)
N7—C8	1.4079 (13)	C9—H9	0.9300
N7—H7N	0.9001	C10—C11	1.3879 (16)
N14—C15	1.3793 (14)	C10—H10	0.9300
N14—C11	1.4148 (14)	C11—C12	1.3898 (16)
N14—H14N	0.9000	C12—C13	1.3799 (15)
N16—C15	1.3385 (14)	C12—H12	0.9300
N16—C17	1.3427 (15)	C13—H13	0.9300
C1—C6	1.3974 (16)	C15—C20	1.3947 (16)
C3—C4	1.3706 (19)	C17—C18	1.3682 (19)
C3—H3	0.9300	C17—H17	0.9300
C4—C5	1.3790 (18)	C18—C19	1.383 (2)
C4—H4	0.9300	C18—H18	0.9300
C5—C6	1.3681 (18)	C19—C20	1.3713 (18)
C5—H5	0.9300	C19—H19	0.9300
C6—H6	0.9300	C20—H20	0.9300
C3—N2—C1	117.93 (10)	C8—C9—H9	119.6
C1—N7—C8	127.71 (9)	C9—C10—C11	121.35 (10)
C1—N7—H7N	114.8	C9—C10—H10	119.3
C8—N7—H7N	115.3	C11—C10—H10	119.3
C15—N14—C11	124.37 (9)	C10—C11—C12	117.74 (10)
C15—N14—H14N	115.1	C10—C11—N14	119.28 (10)
C11—N14—H14N	115.1	C12—C11—N14	122.89 (10)
C15—N16—C17	117.13 (10)	C13—C12—C11	120.99 (10)
N2—C1—N7	114.09 (10)	C13—C12—H12	119.5
N2—C1—C6	121.52 (10)	C11—C12—H12	119.5
N7—C1—C6	124.39 (10)	C12—C13—C8	121.32 (10)
N2—C3—C4	124.16 (11)	C12—C13—H13	119.3
N2—C3—H3	117.9	C8—C13—H13	119.3
C4—C3—H3	117.9	N16—C15—N14	115.68 (10)
C3—C4—C5	117.34 (12)	N16—C15—C20	122.22 (10)
C3—C4—H4	121.3	N14—C15—C20	122.07 (10)
C5—C4—H4	121.3	N16—C17—C18	124.33 (12)
C6—C5—C4	120.31 (12)	N16—C17—H17	117.8
C6—C5—H5	119.8	C18—C17—H17	117.8
C4—C5—H5	119.8	C17—C18—C19	117.84 (12)
C5—C6—C1	118.73 (11)	C17—C18—H18	121.1
C5—C6—H6	120.6	C19—C18—H18	121.1
C1—C6—H6	120.6	C20—C19—C18	119.38 (12)
C13—C8—C9	117.73 (10)	C20—C19—H19	120.3
C13—C8—N7	118.69 (10)	C18—C19—H19	120.3
C9—C8—N7	123.44 (10)	C19—C20—C15	118.97 (12)
C10—C9—C8	120.81 (10)	C19—C20—H20	120.5
C10—C9—H9	119.6	C15—C20—H20	120.5
C3—N2—C1—N7	−179.60 (10)	C15—N14—C11—C10	157.24 (12)
C3—N2—C1—C6	0.15 (16)	C15—N14—C11—C12	−26.30 (18)
C8—N7—C1—N2	178.25 (10)	C10—C11—C12—C13	2.54 (17)
C8—N7—C1—C6	−1.49 (19)	N14—C11—C12—C13	−173.97 (11)
C1—N2—C3—C4	−0.97 (18)	C11—C12—C13—C8	−1.25 (17)
N2—C3—C4—C5	0.9 (2)	C9—C8—C13—C12	−1.05 (17)
C3—C4—C5—C6	−0.1 (2)	N7—C8—C13—C12	−176.94 (10)
C4—C5—C6—C1	−0.7 (2)	C17—N16—C15—N14	−178.51 (11)
N2—C1—C6—C5	0.65 (18)	C17—N16—C15—C20	3.62 (18)
N7—C1—C6—C5	−179.63 (12)	C11—N14—C15—N16	145.45 (11)
C1—N7—C8—C13	−139.63 (12)	C11—N14—C15—C20	−36.68 (18)
C1—N7—C8—C9	44.73 (17)	C15—N16—C17—C18	−1.0 (2)
C13—C8—C9—C10	2.02 (17)	N16—C17—C18—C19	−2.2 (2)
N7—C8—C9—C10	177.69 (11)	C17—C18—C19—C20	2.9 (2)
C8—C9—C10—C11	−0.71 (18)	C18—C19—C20—C15	−0.5 (2)
C9—C10—C11—C12	−1.57 (18)	N16—C15—C20—C19	−2.90 (19)
C9—C10—C11—N14	175.07 (11)	N14—C15—C20—C19	179.36 (12)

D—H···A	D—H	H···A	D···A	D—H···A
N7—H7N···N16i	0.90	2.25	3.1423 (13)	175
N14—H14N···N2ii	0.90	2.12	3.0141 (14)	175

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N7—H7N⋯N16i	0.90	2.25	3.1423 (13)	175
N14—H14N⋯N2ii	0.90	2.12	3.0141 (14)	175

Symmetry codes: (i) ; (ii) .