2,2′,6,6′-Tetra­methyl-4,4′-bipyridine

Fu, L.-H.

doi:10.1107/S1600536807063040

organic compounds

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Volume 64| Part 1| January 2008| Page o127

https://doi.org/10.1107/S1600536807063040

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2,2′,6,6′-Tetramethyl-4,4′-bipyridine

Li-Hai Fu ^a ^*

^aDepartment of Chemistry, TongHua Normal University, 134002, TongHua, Jilin, People's Republic of China
^*Correspondence e-mail: fulihai1973@sina.com

(Received 11 November 2007; accepted 25 November 2007; online 6 December 2007)

In the title compound, C₁₄H₁₆N₂, which has no crystallographic molecular symmetry, the dihedral angle between the least-squares planes of the two pyridine rings is 19.48 (2)°. No classical hydrogen bonds nor π–π interactions were found.

Related literature

For the synthesis of the title compound, see: Hunig & Wehner (1989 ). For related compounds, see: Coles et al. (2002 ); Jackisch et al. (1990 ); Lin et al. (2006 ).

Experimental

Crystal data

C₁₄H₁₆N₂
M_r = 212.29
Tetragonal, I 4₁ /a
a = 21.9827 (10) Å
c = 10.1569 (6) Å
V = 4908.2 (4) Å³
Z = 16
Mo Kα radiation
μ = 0.07 mm⁻¹
T = 293 (2) K
0.32 × 0.26 × 0.26 mm

Data collection

Bruker SMART APEXII diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004 ) T_min = 0.979, T_max = 0.982
14604 measured reflections
2959 independent reflections
2112 reflections with I > 2σ(I)
R_int = 0.031

Refinement

R[F² > 2σ(F²)] = 0.051
wR(F²) = 0.165
S = 1.06
2959 reflections
149 parameters
H-atom parameters constrained
Δρ_max = 0.22 e Å⁻³
Δρ_min = −0.18 e Å⁻³

Table 1
Selected torsion angles (°)

C2—C3—C8—C7	−20.9 (2)
C4—C3—C8—C7	159.85 (14)
C2—C3—C8—C9	159.45 (14)
C4—C3—C8—C9	−19.8 (2)

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2001 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S1600536807063040/om2191sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536807063040/om2191Isup2.hkl

checkCIF report

Comment top

The title compound, C₁₄H₁₆N₂, is a important synthetic intermediate for the preparation of the ligand 4,4'-bipyridine-2,6,2',6'-tetracarboxylic acid, which can be used for constructing open and robust coordination frameworks (Lin et al., 2006).

The molecular structure of the compound is shown in Fig. 1, and selected geometric parameters are given in Table 1. The dihedral angle between the least-squares planes of the two pyridine rings is 19.48 (2) °. This is probably because of steric hindrance, which is similar to related compounds (Coles et al., 2002, Jackisch et al., 1990, Lin et al., 2006), and for this reason the molecule has no symmetry plane.

In the crystal structure no classic hydrogen bonds nor π-π interactions were found (Fig. 2). The molecules may be linked together by weak van der Waals interactions.

Related literature top

For the synthesis of the title compound, see: Hunig & Wehner (1989). For related compounds, see: Coles et al. (2002); Jackisch et al. (1990); Lin et al. (2006).

Experimental top

All reagents were purchased from Aldrich and used without further purification. The compound was synthesized according to a reported method (Hunig & Wehner, 1989). It (0.424 g, 0.002 mol) was dissolved in ethanol (20 ml). After heating at 343 K for 20 min, the mixture was allowed to cool and evaporate naturally. After a few days, yellow crystalline lumps formed. Analysis found: C 79.24, H 7.60, N 13.16%.; C₁₄H₁₆N₂ requires: C 79.20, H 7.60, N 13.20%.

Structure description top

In the crystal structure no classic hydrogen bonds nor π-π interactions were found (Fig. 2). The molecules may be linked together by weak van der Waals interactions.

For the synthesis of the title compound, see: Hunig & Wehner (1989). For related compounds, see: Coles et al. (2002); Jackisch et al. (1990); Lin et al. (2006).

Computing details top

Data collection: APEX2 (Bruker, 2004); cell refinement: SAINT (Bruker, 2004); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2001); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.

Figures top

	Fig. 1. The molecular structure showing the atom-labeling scheme, with displacement ellipsoids drawn at the 30% probability level.
	Fig. 2. The crystal packing, viewed along the c axis.

2,2',6,6'-Tetramethyl-4,4'-bipyridine top

Crystal data top

C₁₄H₁₆N₂	D_x = 1.149 Mg m⁻³
M_r = 212.29	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, I4₁/a	Cell parameters from 352 reflections
a = 21.9827 (10) Å	θ = 2.6–24.8°
c = 10.1569 (6) Å	µ = 0.07 mm⁻¹
V = 4908.2 (4) Å³	T = 293 K
Z = 16	Block, yellow
F(000) = 1824	0.32 × 0.26 × 0.26 mm

Data collection top

Bruker SMART APEXII diffractometer	2959 independent reflections
Radiation source: fine-focus sealed tube	2112 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
φ and ω scans	θ_max = 28.3°, θ_min = 1.9°
Absorption correction: multi-scan (SADABS; Bruker, 2004)	h = −28→28
T_min = 0.979, T_max = 0.982	k = −21→29
14604 measured reflections	l = −12→13

Refinement top

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)] = 0.051	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.165	H-atom parameters constrained
S = 1.06	w = 1/[σ²(F_o²) + (0.0889P)² + 1.2656P] where P = (F_o² + 2F_c²)/3
2959 reflections	(Δ/σ)_max = 0.002
149 parameters	Δρ_max = 0.22 e Å⁻³
0 restraints	Δρ_min = −0.18 e Å⁻³

Crystal data top

C₁₄H₁₆N₂	Z = 16
M_r = 212.29	Mo Kα radiation
Tetragonal, I4₁/a	µ = 0.07 mm⁻¹
a = 21.9827 (10) Å	T = 293 K
c = 10.1569 (6) Å	0.32 × 0.26 × 0.26 mm
V = 4908.2 (4) Å³

Data collection top

Bruker SMART APEXII diffractometer	2959 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2004)	2112 reflections with I > 2σ(I)
T_min = 0.979, T_max = 0.982	R_int = 0.031
14604 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.051	0 restraints
wR(F²) = 0.165	H-atom parameters constrained
S = 1.06	Δρ_max = 0.22 e Å⁻³
2959 reflections	Δρ_min = −0.18 e Å⁻³
149 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

	x	y	z	U_iso*/U_eq
N1	0.36926 (6)	0.13022 (6)	−0.07996 (14)	0.0547 (4)
N2	0.14766 (6)	0.34910 (6)	0.10403 (13)	0.0501 (3)
C1	0.33348 (7)	0.12075 (7)	0.02437 (16)	0.0486 (4)
C2	0.28970 (6)	0.16252 (6)	0.06394 (15)	0.0442 (3)
H2	0.2659	0.1545	0.1377	0.053*
C3	0.28130 (6)	0.21610 (6)	−0.00610 (14)	0.0415 (3)
C4	0.31887 (7)	0.22525 (7)	−0.11452 (16)	0.0509 (4)
H4	0.3149	0.2604	−0.1649	0.061*
C5	0.36228 (7)	0.18207 (8)	−0.14767 (16)	0.0551 (4)
C6	0.14380 (6)	0.29160 (7)	0.14839 (15)	0.0453 (4)
C7	0.18561 (6)	0.24730 (7)	0.11270 (15)	0.0449 (4)
H7	0.1805	0.2075	0.1420	0.054*
C8	0.23495 (6)	0.26192 (6)	0.03364 (14)	0.0411 (3)
C9	0.23940 (7)	0.32206 (6)	−0.00853 (16)	0.0483 (4)
H9	0.2722	0.3343	−0.0600	0.058*
C10	0.19490 (7)	0.36346 (6)	0.02641 (16)	0.0504 (4)
C11	0.34380 (10)	0.06300 (8)	0.1000 (2)	0.0704 (5)
H11A	0.3147	0.0330	0.0727	0.106*
H11B	0.3391	0.0708	0.1924	0.106*
H11C	0.3842	0.0483	0.0832	0.106*
C12	0.40499 (10)	0.19262 (11)	−0.2612 (2)	0.0815 (6)
H12A	0.4440	0.2051	−0.2282	0.122*
H12B	0.3888	0.2238	−0.3173	0.122*
H12C	0.4094	0.1556	−0.3106	0.122*
C13	0.09245 (7)	0.27763 (9)	0.24106 (17)	0.0588 (4)
H13A	0.1058	0.2836	0.3301	0.088*
H13B	0.0799	0.2361	0.2295	0.088*
H13C	0.0588	0.3042	0.2228	0.088*
C14	0.19686 (10)	0.42776 (8)	−0.0243 (2)	0.0759 (6)
H14A	0.1633	0.4344	−0.0832	0.114*
H14B	0.2344	0.4344	−0.0703	0.114*
H14C	0.1940	0.4556	0.0484	0.114*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
N1	0.0522 (7)	0.0543 (8)	0.0574 (8)	0.0114 (6)	0.0035 (6)	−0.0052 (6)
N2	0.0475 (7)	0.0470 (7)	0.0558 (8)	0.0060 (5)	0.0012 (6)	−0.0011 (6)
C1	0.0492 (8)	0.0439 (8)	0.0527 (9)	0.0059 (6)	−0.0042 (7)	−0.0017 (6)
C2	0.0426 (7)	0.0413 (7)	0.0487 (8)	0.0012 (6)	0.0013 (6)	0.0010 (6)
C3	0.0363 (7)	0.0388 (7)	0.0495 (8)	−0.0006 (5)	−0.0014 (6)	−0.0011 (6)
C4	0.0512 (8)	0.0480 (8)	0.0537 (9)	0.0045 (6)	0.0070 (7)	0.0061 (7)
C5	0.0518 (9)	0.0597 (10)	0.0539 (9)	0.0059 (7)	0.0080 (7)	−0.0024 (7)
C6	0.0385 (7)	0.0505 (8)	0.0469 (8)	0.0001 (6)	−0.0023 (6)	−0.0008 (6)
C7	0.0427 (7)	0.0400 (7)	0.0519 (8)	−0.0006 (6)	0.0013 (6)	0.0047 (6)
C8	0.0384 (7)	0.0380 (7)	0.0470 (8)	0.0010 (5)	−0.0017 (6)	0.0004 (6)
C9	0.0446 (8)	0.0423 (8)	0.0579 (9)	0.0005 (6)	0.0063 (7)	0.0056 (6)
C10	0.0503 (8)	0.0403 (8)	0.0606 (9)	0.0038 (6)	0.0010 (7)	0.0022 (7)
C11	0.0815 (13)	0.0534 (10)	0.0764 (13)	0.0223 (9)	0.0073 (10)	0.0065 (9)
C12	0.0752 (13)	0.0951 (15)	0.0743 (13)	0.0159 (11)	0.0300 (10)	0.0069 (11)
C13	0.0466 (9)	0.0706 (11)	0.0590 (10)	0.0001 (7)	0.0070 (7)	0.0017 (8)
C14	0.0772 (13)	0.0447 (9)	0.1057 (16)	0.0116 (8)	0.0158 (11)	0.0139 (9)

Geometric parameters (Å, º) top

N1—C1	1.336 (2)	C8—C9	1.3931 (19)
N1—C5	1.340 (2)	C9—C10	1.383 (2)
N2—C10	1.341 (2)	C9—H9	0.9300
N2—C6	1.3446 (19)	C10—C14	1.505 (2)
C1—C2	1.389 (2)	C11—H11A	0.9600
C1—C11	1.501 (2)	C11—H11B	0.9600
C2—C3	1.3885 (19)	C11—H11C	0.9600
C2—H2	0.9300	C12—H12A	0.9600
C3—C4	1.391 (2)	C12—H12B	0.9600
C3—C8	1.4886 (19)	C12—H12C	0.9600
C4—C5	1.388 (2)	C13—H13A	0.9600
C4—H4	0.9300	C13—H13B	0.9600
C5—C12	1.505 (2)	C13—H13C	0.9600
C6—C7	1.387 (2)	C14—H14A	0.9600
C6—C13	1.502 (2)	C14—H14B	0.9600
C7—C8	1.3873 (19)	C14—H14C	0.9600
C7—H7	0.9300

C1—N1—C5	118.18 (13)	C8—C9—H9	120.1
C10—N2—C6	117.84 (12)	N2—C10—C9	122.93 (13)
N1—C1—C2	122.29 (14)	N2—C10—C14	116.37 (14)
N1—C1—C11	116.65 (14)	C9—C10—C14	120.69 (15)
C2—C1—C11	121.04 (15)	C1—C11—H11A	109.5
C3—C2—C1	120.29 (14)	C1—C11—H11B	109.5
C3—C2—H2	119.9	H11A—C11—H11B	109.5
C1—C2—H2	119.9	C1—C11—H11C	109.5
C2—C3—C4	116.71 (13)	H11A—C11—H11C	109.5
C2—C3—C8	121.74 (13)	H11B—C11—H11C	109.5
C4—C3—C8	121.55 (13)	C5—C12—H12A	109.5
C5—C4—C3	120.10 (14)	C5—C12—H12B	109.5
C5—C4—H4	120.0	H12A—C12—H12B	109.5
C3—C4—H4	120.0	C5—C12—H12C	109.5
N1—C5—C4	122.42 (15)	H12A—C12—H12C	109.5
N1—C5—C12	116.94 (15)	H12B—C12—H12C	109.5
C4—C5—C12	120.63 (16)	C6—C13—H13A	109.5
N2—C6—C7	122.05 (13)	C6—C13—H13B	109.5
N2—C6—C13	116.73 (13)	H13A—C13—H13B	109.5
C7—C6—C13	121.21 (14)	C6—C13—H13C	109.5
C6—C7—C8	120.44 (13)	H13A—C13—H13C	109.5
C6—C7—H7	119.8	H13B—C13—H13C	109.5
C8—C7—H7	119.8	C10—C14—H14A	109.5
C7—C8—C9	116.92 (13)	C10—C14—H14B	109.5
C7—C8—C3	122.38 (12)	H14A—C14—H14B	109.5
C9—C8—C3	120.70 (13)	C10—C14—H14C	109.5
C10—C9—C8	119.74 (13)	H14A—C14—H14C	109.5
C10—C9—H9	120.1	H14B—C14—H14C	109.5

C5—N1—C1—C2	0.2 (2)	N2—C6—C7—C8	2.9 (2)
C5—N1—C1—C11	−178.33 (16)	C13—C6—C7—C8	−175.91 (14)
N1—C1—C2—C3	0.7 (2)	C6—C7—C8—C9	−1.0 (2)
C11—C1—C2—C3	179.13 (15)	C6—C7—C8—C3	179.37 (13)
C1—C2—C3—C4	−0.6 (2)	C2—C3—C8—C7	−20.9 (2)
C1—C2—C3—C8	−179.86 (13)	C4—C3—C8—C7	159.85 (14)
C2—C3—C4—C5	−0.3 (2)	C2—C3—C8—C9	159.45 (14)
C8—C3—C4—C5	178.97 (14)	C4—C3—C8—C9	−19.8 (2)
C1—N1—C5—C4	−1.1 (2)	C7—C8—C9—C10	−1.5 (2)
C1—N1—C5—C12	177.52 (16)	C3—C8—C9—C10	178.14 (14)
C3—C4—C5—N1	1.2 (3)	C6—N2—C10—C9	−0.4 (2)
C3—C4—C5—C12	−177.38 (16)	C6—N2—C10—C14	178.45 (16)
C10—N2—C6—C7	−2.2 (2)	C8—C9—C10—N2	2.3 (3)
C10—N2—C6—C13	176.71 (14)	C8—C9—C10—C14	−176.52 (16)

Experimental details

Crystal data
Chemical formula	C₁₄H₁₆N₂
M_r	212.29
Crystal system, space group	Tetragonal, I4₁/a
Temperature (K)	293
a, c (Å)	21.9827 (10), 10.1569 (6)
V (Å³)	4908.2 (4)
Z	16
Radiation type	Mo Kα
µ (mm⁻¹)	0.07
Crystal size (mm)	0.32 × 0.26 × 0.26

Data collection
Diffractometer	Bruker SMART APEXII
Absorption correction	Multi-scan (SADABS; Bruker, 2004)
T_min, T_max	0.979, 0.982
No. of measured, independent and observed [I > 2σ(I)] reflections	14604, 2959, 2112
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.667

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.051, 0.165, 1.06
No. of reflections	2959
No. of parameters	149
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.18

Computer programs: APEX2 (Bruker, 2004), SAINT (Bruker, 2004), SAINT, SHELXTL (Sheldrick, 2001), SHELXTL and local programs.

Selected torsion angles (º) top

C2—C3—C8—C7	−20.9 (2)	C2—C3—C8—C9	159.45 (14)
C4—C3—C8—C7	159.85 (14)	C4—C3—C8—C9	−19.8 (2)

References

Bruker (2004). APEX2 (Version 1.08), SAINT (Version 7.03) and SADABS (Version 2.11). Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar
Coles, S. J., Holmes, R., Hursthouse, M. B. & Price, D. J. (2002). Acta Cryst. E58, o626–o628. Web of Science CSD CrossRef CAS IUCr Journals Google Scholar
Hunig, S. & Wehner, I. (1989). Synthesis, pp. 552–554. CrossRef Google Scholar
Jackisch, M. A., Fronczek, F. R., Geiger, C. C., Hale, P. S., Daly, W. H. & Butler, L. G. (1990). Acta Cryst. C46, 919–922. CSD CrossRef CAS Web of Science IUCr Journals Google Scholar
Lin, X., Blake, A. J., Wilson, C., Sun, X. Z., Champness, N. R., George, M. W., Hubberstey, P., Mokaya, R. & Schroder, M. (2006). J. Am. Chem. Soc. 128, 10745–10753. Web of Science CSD CrossRef PubMed CAS Google Scholar
Sheldrick, G. M. (2001). SHELXTL. Version 6.10. Bruker AXS Inc., Madison, Wisconsin, USA. Google Scholar