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organic compounds\(\def\hfill{\hskip 5em}\def\hfil{\hskip 3em}\def\eqno#1{\hfil {#1}}\)

Journal logoCRYSTALLOGRAPHIC
COMMUNICATIONS
ISSN: 2056-9890
Volume 67| Part 11| November 2011| Page o3095
doi:10.1107/S1600536811044539

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

Barbara Wichera and Maria Gdanieca*

aFaculty of Chemistry, Adam Mickiewicz University, 60-780 Poznań, Poland
*Correspondence e-mail: magdan@amu.edu.pl

(Received 21 October 2011; accepted 25 October 2011; online 29 October 2011)

A third polymorph of the title compound, C16H14N4, has been obtained. The mol­ecule adopts a non-planar conformation with an E configuration at the two partially double exo C N bonds of the 2-pyridyl­amine units. Like in the triclinic form [Bensemann et al. (2002[Bensemann, I., Gdaniec, M. & Połoński, T. (2002). New J. Chem. 26, 448-456.]). New J. Chem. 26, 448–456], the recognition process between 2-pyridyl­amine units takes place through formation of a cyclic R22(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[Bensemann, I., Gdaniec, M. & Połoński, T. (2002). New J. Chem. 26, 448-456.]).

[Scheme 1]

Experimental

Crystal data

  • C16H14N4

  • Mr = 262.31

  • Monoclinic, P 21 /c

  • 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[Agilent (2010). CrysAlis PRO. Agilent Technologies, Yarnton, England.]) Tmin = 0.799, Tmax = 1.000

  • 10413 measured reflections

  • 2398 independent reflections

  • 2221 reflections with I > 2/s(I)

  • Rint = 0.019
Refinement

  • R[F2 > 2σ(F2)] = 0.035

  • wR(F2) = 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

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) x, y, z+1; (ii) x, y, z-1.

Data collection: CrysAlis PRO (Agilent, 2010[Agilent (2010). CrysAlis PRO. Agilent Technologies, Yarnton, England.]); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SIR2004 (Burla et al., 2005[Burla, M. C., Caliandro, R., Camalli, M., Carrozzini, B., Cascarano, G. L., De Caro, L., Giacovazzo, C., Polidori, G. & Spagna, R. (2005). J. Appl. Cryst. 38, 381-388.]); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008[Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.]); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997[Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.]) and Mercury (Macrae et al., 2006[Macrae, C. F., Edgington, P. R., McCabe, P., Pidcock, E., Shields, G. P., Taylor, R., Towler, M. & van de Streek, J. (2006). J. Appl. Cryst. 39, 453-457.]); software used to prepare material for publication: SHELXL97.

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811044539/rz2657sup1.cif

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

Supporting information file. DOI: 10.1107/S1600536811044539/rz2657Isup3.cml

checkCIF report


Comment top

The compounds bearing two 2-pyridylamine groups separated by linkers can adopt either E,E, Z,Z or E,Z forms depending on the configuration of the partially double exo C≐ N bond of the 2-pyridylamine unit. In crystals the molecules in the E, E form tend to build one-dimensional networks via R22(8) synthons generated between self-complementary 2-pyridylamine groups. In turn, the Z,Z form generates the C(4) catemer motif that can lead to the formation of one-, two- and three-dimensional frameworks (Bensemann et al., 2002). These compounds are known to exhibit conformational polymorphism and for N,N'-di(pyridin-2-yl)benzene-1,4-diamine two polymorphic forms were identified. In the orthorhombic form (Pbca, Z'=0.5), obtained by crystallization from acetonitrile, the molecules are nonplanar and adopt the Z,Z form. Hydrogen bonds between 2-pyridylamine groups generate catemeric motifs that assemble molecules into a two-dimensional framework. In the triclinic P1 polymorph, obtained by crystallization from methanol, there are two symmetry independent molecules, each in the E,E form and located around inversion center. These molecules form tapes via strongly nonplanar R22(8) motif generated by N—H···N hydrogen bonds (Bensemann et al., 2002).

Recently, during an attempt to cocrystallize N,N'-di(pyridin-2-yl)benzene-1,4-diamine with pyrazine from 2-butanone, a new monoclinic polymorph of N,N'-di(pyridin-2-yl)benzene-1,4-diamine was obtained. When crystallization was repeated from 2-butanone without addition of pyrazine the triclinic polymorph was formed.

In the new monoclinic polymorph the molecules adopt the E,E form and are assembled into tapes via strongly non-planar R22(8) hydrogen-bond motif. The overall shape of the tapes and their crystal packing are different from the arrangement found in the triclinic polymorph. As shown in Fig. 2a, the hydrogen-bonded tapes extended along [0 0 1] are grouped into pairs, with no specific interactions occurring between the two tapes, and these pairs of tapes are further arranged in a herring-bone manner (Fig. 2b).

The three polymorphs of N,N'-di(pyridin-2-yl)benzene-1,4-diamine have identical or very similar melting points: 478–479 K for the orthorhombic and triclinic polymorphs and 479 K for the monoclinic form. The calculated crystal densities are also similar: 1.335, 1.314 and 1.328 g cm-3 for orthorhombic, triclinic and monoclinic forms, respectively.

Related literature top

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 top

N,N'-Di(pyridin-2-yl)benzene-1,4-diamine was prepared according to the published procedure (Bensemann et al., 2002). N,N'-Di(pyridin-2-yl)benzene-1,4-diamine (0.03 g, 0.11 mmol) and pyrazine (0.01 g, 0.11 mmol) were dissolved in 5 ml of 2-butanone and placed in a glass vial. After a few days colourless, plate-shaped crystals with a melting point of 479 K were obtained.

Refinement top

H atoms of the N—H groups were located in difference electron-density maps. N—H bond lengths were standardized to 0.90 Å and Uiso(H) values were constrained to 1.2Ueq(N). All other H atoms were initially identified in difference maps but were placed at calculated positions with C—H = 0.93 Å, and were refined as riding on their carrier atoms with Uiso(H) = 1.2Ueq(C).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2010); cell refinement: CrysAlis PRO (Agilent, 2010); data reduction: CrysAlis PRO (Agilent, 2010); 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 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. : The asymmetric unit of the title compound with displacement ellipsoids shown at the 50% probability level.
[Figure 2] Fig. 2. : Crystal packing in the monoclinic polymorph of the title compound: (a) a pair of hydrogen bonded tapes extended along [0 0 1] and (b) herring-bone packing of the pairs of tapes (one pair is show with a black rhomboid). Hydrogen bonds are shown with dashed lines.
N,N'-bis(pyridin-2-yl)benzene-1,4-diamine top
Crystal data top
C16H14N4F(000) = 552
Mr = 262.31Dx = 1.328 Mg m−3
Monoclinic, P21/cMelting point: 479 K
Hall symbol: -P 2ybcCu Kα radiation, λ = 1.54178 Å
a = 7.2534 (2) ÅCell parameters from 6262 reflections
b = 20.8270 (6) Åθ = 2.1–75.8°
c = 9.0681 (3) ŵ = 0.65 mm−1
β = 106.746 (4)°T = 295 K
V = 1311.79 (7) Å3Plate, colourless
Z = 40.2 × 0.2 × 0.05 mm
Data collection top
Oxford Diffraction SuperNova
diffractometer		2398 independent reflections
Radiation source: Nova Cu X-ray Source2221 reflections with I > 2/s(I)
Mirror monochromatorRint = 0.019
ω scansθmax = 68.2°, θmin = 6.4°
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)		h = −8→8
Tmin = 0.799, Tmax = 1.000k = −25→25
10413 measured reflectionsl = −10→10
Refinement top
Refinement on F2Primary atom site location: structure-invariant direct methods
Least-squares matrix: fullSecondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.035Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.094H-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 parametersΔρmax = 0.11 e Å−3
0 restraintsΔρmin = −0.19 e Å−3
Crystal data top
C16H14N4V = 1311.79 (7) Å3
Mr = 262.31Z = 4
Monoclinic, P21/cCu Kα radiation
a = 7.2534 (2) ŵ = 0.65 mm−1
b = 20.8270 (6) ÅT = 295 K
c = 9.0681 (3) Å0.2 × 0.2 × 0.05 mm
β = 106.746 (4)°
Data collection top
Oxford Diffraction SuperNova
diffractometer		2398 independent reflections
Absorption correction: multi-scan
(CrysAlis PRO; Agilent, 2010)		2221 reflections with I > 2/s(I)
Tmin = 0.799, Tmax = 1.000Rint = 0.019
10413 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.0350 restraints
wR(F2) = 0.094H-atom parameters constrained
S = 1.07Δρmax = 0.11 e Å−3
2398 reflectionsΔρmin = −0.19 e Å−3
181 parameters
Special details top

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
N20.18091 (14)0.15267 (5)0.53715 (10)0.0434 (2)
N70.34929 (14)0.13813 (5)0.36249 (10)0.0453 (2)
H7N0.42660.11420.43800.054*
N140.53458 (15)0.12536 (5)−0.19925 (11)0.0521 (3)
H14N0.43140.1319−0.28110.063*
N160.63876 (14)0.06275 (5)−0.36845 (10)0.0458 (2)
C10.18087 (15)0.15794 (5)0.38962 (12)0.0382 (2)
C30.02222 (18)0.17053 (6)0.57328 (14)0.0500 (3)
H30.02160.16630.67520.060*
C4−0.13952 (18)0.19473 (7)0.46964 (16)0.0572 (3)
H4−0.24620.20710.50000.069*
C5−0.13771 (18)0.19995 (7)0.31846 (16)0.0581 (3)
H5−0.24490.21610.24480.070*
C60.02097 (17)0.18144 (6)0.27640 (13)0.0486 (3)
H60.02240.18440.17440.058*
C80.39192 (15)0.13618 (5)0.22059 (12)0.0387 (3)
C90.34861 (17)0.18587 (5)0.11355 (13)0.0435 (3)
H90.28420.22200.13320.052*
C100.40017 (17)0.18215 (6)−0.02162 (12)0.0445 (3)
H100.36850.2157−0.09200.053*
C110.49825 (15)0.12933 (5)−0.05437 (12)0.0406 (3)
C120.54745 (16)0.08080 (5)0.05517 (13)0.0425 (3)
H120.61770.04570.03800.051*
C130.49368 (16)0.08396 (5)0.18909 (13)0.0419 (3)
H130.52620.05050.25970.050*
C150.67958 (16)0.08914 (5)−0.22815 (12)0.0418 (3)
C170.7754 (2)0.02598 (6)−0.39897 (15)0.0539 (3)
H170.74770.0068−0.49550.065*
C180.9526 (2)0.01483 (7)−0.29741 (16)0.0603 (4)
H181.0408−0.0122−0.32280.072*
C190.99619 (18)0.04509 (7)−0.15578 (15)0.0574 (3)
H191.11730.0402−0.08550.069*
C200.85928 (17)0.08235 (7)−0.11991 (14)0.0506 (3)
H200.88580.1028−0.02490.061*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
N20.0485 (5)0.0489 (5)0.0360 (5)0.0011 (4)0.0174 (4)0.0017 (4)
N70.0482 (5)0.0582 (6)0.0316 (5)0.0106 (4)0.0148 (4)0.0050 (4)
N140.0529 (6)0.0744 (7)0.0294 (5)0.0220 (5)0.0123 (4)0.0021 (4)
N160.0504 (6)0.0555 (6)0.0349 (5)0.0066 (4)0.0177 (4)0.0011 (4)
C10.0431 (6)0.0385 (5)0.0343 (5)−0.0050 (4)0.0132 (4)−0.0027 (4)
C30.0539 (7)0.0573 (7)0.0456 (6)−0.0034 (5)0.0253 (5)−0.0006 (5)
C40.0427 (6)0.0708 (9)0.0636 (8)−0.0016 (6)0.0242 (6)−0.0007 (6)
C50.0386 (6)0.0760 (9)0.0563 (8)−0.0020 (6)0.0081 (5)0.0052 (6)
C60.0438 (6)0.0638 (7)0.0365 (6)−0.0053 (5)0.0090 (5)−0.0002 (5)
C80.0403 (6)0.0454 (6)0.0313 (5)0.0006 (4)0.0117 (4)−0.0013 (4)
C90.0497 (6)0.0445 (6)0.0392 (6)0.0108 (5)0.0174 (5)0.0014 (5)
C100.0505 (6)0.0488 (6)0.0352 (6)0.0122 (5)0.0139 (5)0.0080 (5)
C110.0409 (6)0.0511 (6)0.0302 (5)0.0054 (5)0.0108 (4)−0.0014 (4)
C120.0465 (6)0.0415 (6)0.0411 (6)0.0078 (5)0.0150 (5)−0.0023 (4)
C130.0474 (6)0.0413 (6)0.0377 (6)0.0046 (5)0.0134 (5)0.0051 (4)
C150.0471 (6)0.0488 (6)0.0335 (5)0.0057 (5)0.0178 (5)0.0048 (4)
C170.0630 (8)0.0606 (7)0.0455 (7)0.0103 (6)0.0273 (6)−0.0004 (5)
C180.0604 (8)0.0689 (8)0.0618 (8)0.0204 (6)0.0337 (7)0.0123 (7)
C190.0445 (7)0.0763 (9)0.0538 (7)0.0105 (6)0.0180 (6)0.0175 (6)
C200.0489 (7)0.0660 (8)0.0373 (6)0.0036 (5)0.0131 (5)0.0023 (5)
Geometric parameters (Å, º) top
N2—C31.3372 (15)C8—C131.3895 (15)
N2—C11.3422 (13)C8—C91.3916 (15)
N7—C11.3771 (14)C9—C101.3829 (15)
N7—C81.4079 (13)C9—H90.9300
N7—H7N0.9001C10—C111.3879 (16)
N14—C151.3793 (14)C10—H100.9300
N14—C111.4148 (14)C11—C121.3898 (16)
N14—H14N0.9000C12—C131.3799 (15)
N16—C151.3385 (14)C12—H120.9300
N16—C171.3427 (15)C13—H130.9300
C1—C61.3974 (16)C15—C201.3947 (16)
C3—C41.3706 (19)C17—C181.3682 (19)
C3—H30.9300C17—H170.9300
C4—C51.3790 (18)C18—C191.383 (2)
C4—H40.9300C18—H180.9300
C5—C61.3681 (18)C19—C201.3713 (18)
C5—H50.9300C19—H190.9300
C6—H60.9300C20—H200.9300
C3—N2—C1117.93 (10)C8—C9—H9119.6
C1—N7—C8127.71 (9)C9—C10—C11121.35 (10)
C1—N7—H7N114.8C9—C10—H10119.3
C8—N7—H7N115.3C11—C10—H10119.3
C15—N14—C11124.37 (9)C10—C11—C12117.74 (10)
C15—N14—H14N115.1C10—C11—N14119.28 (10)
C11—N14—H14N115.1C12—C11—N14122.89 (10)
C15—N16—C17117.13 (10)C13—C12—C11120.99 (10)
N2—C1—N7114.09 (10)C13—C12—H12119.5
N2—C1—C6121.52 (10)C11—C12—H12119.5
N7—C1—C6124.39 (10)C12—C13—C8121.32 (10)
N2—C3—C4124.16 (11)C12—C13—H13119.3
N2—C3—H3117.9C8—C13—H13119.3
C4—C3—H3117.9N16—C15—N14115.68 (10)
C3—C4—C5117.34 (12)N16—C15—C20122.22 (10)
C3—C4—H4121.3N14—C15—C20122.07 (10)
C5—C4—H4121.3N16—C17—C18124.33 (12)
C6—C5—C4120.31 (12)N16—C17—H17117.8
C6—C5—H5119.8C18—C17—H17117.8
C4—C5—H5119.8C17—C18—C19117.84 (12)
C5—C6—C1118.73 (11)C17—C18—H18121.1
C5—C6—H6120.6C19—C18—H18121.1
C1—C6—H6120.6C20—C19—C18119.38 (12)
C13—C8—C9117.73 (10)C20—C19—H19120.3
C13—C8—N7118.69 (10)C18—C19—H19120.3
C9—C8—N7123.44 (10)C19—C20—C15118.97 (12)
C10—C9—C8120.81 (10)C19—C20—H20120.5
C10—C9—H9119.6C15—C20—H20120.5
C3—N2—C1—N7−179.60 (10)C15—N14—C11—C10157.24 (12)
C3—N2—C1—C60.15 (16)C15—N14—C11—C12−26.30 (18)
C8—N7—C1—N2178.25 (10)C10—C11—C12—C132.54 (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—C50.9 (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—C50.65 (18)C17—N16—C15—C203.62 (18)
N7—C1—C6—C5−179.63 (12)C11—N14—C15—N16145.45 (11)
C1—N7—C8—C13−139.63 (12)C11—N14—C15—C20−36.68 (18)
C1—N7—C8—C944.73 (17)C15—N16—C17—C18−1.0 (2)
C13—C8—C9—C102.02 (17)N16—C17—C18—C19−2.2 (2)
N7—C8—C9—C10177.69 (11)C17—C18—C19—C202.9 (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—N14175.07 (11)N14—C15—C20—C19179.36 (12)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N7—H7N···N16i0.902.253.1423 (13)175
N14—H14N···N2ii0.902.123.0141 (14)175
Symmetry codes: (i) x, y, z+1; (ii) x, y, z−1.

Experimental details

Crystal data
Chemical formulaC16H14N4
Mr262.31
Crystal system, space groupMonoclinic, P21/c
Temperature (K)295
a, b, c (Å)7.2534 (2), 20.8270 (6), 9.0681 (3)
β (°) 106.746 (4)
V (Å3)1311.79 (7)
Z4
Radiation typeCu Kα
µ (mm−1)0.65
Crystal size (mm)0.2 × 0.2 × 0.05
Data collection
DiffractometerOxford Diffraction SuperNova
diffractometer
Absorption correctionMulti-scan
(CrysAlis PRO; Agilent, 2010)
Tmin, Tmax0.799, 1.000
No. of measured, independent and
observed [I > 2/s(I)] reflections		10413, 2398, 2221
Rint0.019
(sin θ/λ)max (Å−1)0.602
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.035, 0.094, 1.07
No. of reflections2398
No. of parameters181
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å−3)0.11, −0.19

Computer programs: CrysAlis PRO (Agilent, 2010), SIR2004 (Burla et al., 2005), SHELXL97 (Sheldrick, 2008), ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2006).

Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
N7—H7N···N16i0.902.253.1423 (13)175
N14—H14N···N2ii0.902.123.0141 (14)175
Symmetry codes: (i) x, y, z+1; (ii) x, y, z−1.
 

References

First citationAgilent (2010). CrysAlis PRO. Agilent Technologies, Yarnton, England.  Google Scholar
 First citationBensemann, I., Gdaniec, M. & Połoński, T. (2002). New J. Chem. 26, 448–456.  Web of Science CSD CrossRef CAS Google Scholar
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Journal logoCRYSTALLOGRAPHIC
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ISSN: 2056-9890
Volume 67| Part 11| November 2011| Page o3095
doi:10.1107/S1600536811044539
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