1,2,4,5-Tetra­fluoro-3,6-diiodo­benzene–2,3-bis­(pyridin-2-yl)pyrazine (1/1)

Arman, H.D.; Kaulgud, T.; Tiekink, E.R.T.

doi:10.1107/S1600536810041668

Volume 66
Part 11
Page o2885
November 2010

Received 14 October 2010
Accepted 15 October 2010
Online 23 October 2010

Key indicators
Single-crystal X-ray study
T = 98 K
Mean (C-C) = 0.007 Å
R = 0.039
wR = 0.109
Data-to-parameter ratio = 13.9
Details

1,2,4,5-Tetrafluoro-3,6-diiodobenzene-2,3-bis(pyridin-2-yl)pyrazine (1/1)

Hadi D. Arman,^a Trupta Kaulgud ^a and Edward R. T. Tiekink ^b ^*

^aDepartment of Chemistry, The University of Texas at San Antonio, One UTSA Circle, San Antonio, Texas 78249-0698, USA, and ^bDepartment of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia
Correspondence e-mail: Edward.Tiekink@gmail.com

The components of the title 1:1 co-crystal, C₁₄H₁₀N₄·C₆F₄I₂, are connected via an NI [2.959 (4) Å] halogen bond, in which the N atom is part of the relatively electron-rich pyrazine ring. The C₆F₄I₂ molecule is almost planar [r.m.s. deviation = 0.038 Å] but there are significant twists in the pyrazine derivative, as seen in the dihedral angles [31.3 (2) and 54.6 (2)°] formed between the pendant pyridyl rings and the central pyrazine ring. The bimolecular aggregates are sustained in the crystal by C-HF and [pi] - [pi] interactions [ring centroid(pyridyl)-ring centroid(benzene) = 3.678 (3) Å].

Related literature

For related studies on co-crystal formation, see: Broker & Tiekink (2007); Broker et al. (2008); Arman et al. (2010). For background to halogen bonding, see: Metrangolo et al. (2008); Pennington et al. (2008).

Experimental

Crystal data

C₁₄H₁₀N₄·C₆F₄I₂
M_r = 636.04
Triclinic, $[P \overline 1]$
a = 6.3997 (15) Å
b = 10.737 (2) Å
c = 15.092 (4) Å
= 74.237 (10)°
= 85.877 (11)°
= 80.283 (12)°
V = 983.3 (4) Å³
Z = 2
Mo K radiation
= 3.25 mm^-1
T = 98 K
0.40 × 0.13 × 0.07 mm

Data collection

Rigaku AFC12/SATURN724 diffractometer
Absorption correction: multi-scan (ABSCOR; Higashi, 1995) T_min = 0.504, T_max = 1.000
5074 measured reflections
3775 independent reflections
3550 reflections with I > 2(I)
R_int = 0.025

Refinement

R[F² > 2(F²)] = 0.039
wR(F²) = 0.109
S = 1.09
3775 reflections
271 parameters
H-atom parameters constrained
_max = 1.32 e Å^-3
_min = -1.20 e Å^-3

Table 1
Hydrogen-bond geometry (Å, °)

D-HA	D-H	HA	DA	D-HA
C8-H8F4	0.95	2.54	3.145 (6)	121
C9-H9F4	0.95	2.46	3.100 (6)	125
C18-H18F2ⁱ	0.95	2.52	3.341 (7)	144
Symmetry code: (i) x+1, y+1, z-1.

Data collection: CrystalClear (Molecular Structure Corporation & Rigaku, 2005); cell refinement: CrystalClear; data reduction: CrystalClear; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Supplementary data and figures for this paper are available from the IUCr electronic archives (Reference: HB5683 ).

References

Arman, H. D., Kaulgud, T. & Tiekink, E. R. T. (2010). Acta Cryst. E66, o2683.
Brandenburg, K. (2006). DIAMOND. Crystal Impact GbR, Bonn, Germany.
Broker, G. A., Bettens, R. P. A. & Tiekink, E. R. T. (2008). CrystEngComm, 10, 879-887.
Broker, G. A. & Tiekink, E. R. T. (2007). CrystEngComm, 9, 1096-1109.
Farrugia, L. J. (1997). J. Appl. Cryst. 30, 565.
Higashi, T. (1995). ABSCOR. Rigaku Corporation, Tokyo, Japan.
Metrangolo, P., Resnati, G., Pilati, T. & Biella, S. (2008). Struct. Bond. 126, 105-136.
Molecular Structure Corporation & Rigaku (2005). CrystalClear. MSC, The Woodlands, Texas, USA, and Rigaku Corporation, Tokyo, Japan.
Pennington, W. T., Hanks, T. W. & Arman, H. D. (2008). Struct. Bond. 126, 65-104.
Sheldrick, G. M. (2008). Acta Cryst. A64, 112-122.
Westrip, S. P. (2010). J. Appl. Cryst. 43, 920-925.

organic compounds