The halogen-bonded adduct 1,4-bis(pyri­din-4-yl)buta-1,3-diyne–1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8-hexa­deca­fluoro-1,8-diiodo­octane (1/1)

Gabriella Cavallo; Giovanni Marras; Pierangelo Metrangolo; Tullio Pilati; Giancarlo Terraneo

doi:10.1107/S1600536813001888

. 2013 Feb 2;69(Pt 3):o328–o329. doi: 10.1107/S1600536813001888

The halogen-bonded adduct 1,4-bis(pyridin-4-yl)buta-1,3-diyne–1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8-hexadecafluoro-1,8-diiodooctane (1/1)

Gabriella Cavallo ^a, Giovanni Marras ^b, Pierangelo Metrangolo ^a, Tullio Pilati ^a, Giancarlo Terraneo ^a,^*

PMCID: PMC3588426 PMID: 23476525

Abstract

In the crystal structure of the title compound, C₈F₁₆I₂·C₁₄H₈N₂, the molecules form infinite chains parallel to [2-11] through two symmetry-independent C—I⋯N halogen bonds (XBs). As commonly found, the perfluoroalkyl molecules segregate from the hydrocarbon ones, forming a layered structure. Apart from the XBs, the only contact below the sum of van der Waals radii is a weak H⋯F contact. The topology of the network is a nice example of the paradigm of the expansion of ditopic starting modules; the XB leads to the construction of infinite supramolecular chains along [2-11] formed by alternating XB donors and acceptors.

Related literature

For the use of bis-(4-pyridyl)buta-1,3-diine in crystal engeneering based on hydrogen bonding and transition metal binding, see: Nakamura et al. (2003 ▶); Curtis et al. (2005 ▶); Maekawa et al. (2000 ▶); Badruz Zaman et al. (2001 ▶); Allan et al. (1988 ▶). For N⋯I halogen bonds based on α,ω-diiodoperfluorocarbons, see: Neukirch et al. (2005 ▶); Navarrini et al. (2000 ▶); Liantonio et al. (2003 ▶); Bertani et al. (2002 ▶); Metrangolo et al. (2004 ▶, 2008 ▶); Fox et al. (2004 ▶); Dey et al. (2009 ▶). For segregation of perfluoroalkyl chains, see: Fox et al. (2008 ▶). For chirality and order/disorder of long perfluoroalkyl chains, see: Monde et al. (2006 ▶). For the synthesis of bis-(4-pyridyl)buta-1,3-diine, see: Della Ciana & Haim (1984 ▶). graphic file with name e-69-0o328-scheme1.jpg

Experimental

Crystal data

C₈F₁₆I₂·C₁₄H₈N₂
M _r = 858.10
Triclinic,
a = 5.4849 (11) Å
b = 14.302 (2) Å
c = 18.354 (3) Å
α = 111.40 (2)°
β = 90.35 (2)°
γ = 94.03 (2)°
V = 1336.4 (4) Å³
Z = 2
Mo Kα radiation
μ = 2.48 mm⁻¹
T = 295 K
0.36 × 0.12 × 0.10 mm

Data collection

Bruker SMART CCD area detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2010 ▶) T _min = 0.734, T _max = 1.000
15067 measured reflections
6100 independent reflections
4600 reflections with I > 2σ(I)
R _int = 0.026

Refinement

R[F ² > 2σ(F ²)] = 0.039
wR(F ²) = 0.114
S = 1.02
6100 reflections
379 parameters
H-atom parameters constrained
Δρ_max = 0.90 e Å⁻³
Δρ_min = −0.57 e Å⁻³

Data collection: APEX2 (Bruker, 2010 ▶); cell refinement: SAINT (Bruker, 2010 ▶); data reduction: SAINT; program(s) used to solve structure: SIR2002 (Burla et al., 2003 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012 ▶) and Mercury (Macrae et al., 2006 ▶); software used to prepare material for publication: enCIFer (Allen et al., 2004 ▶).

Supplementary Material

Click here for additional data file.^{(29.7KB, cif)}

Crystal structure: contains datablock(s) global, I. DOI: 10.1107/S1600536813001888/fy2080sup1.cif

e-69-0o328-sup1.cif^{(29.7KB, cif)}

Click here for additional data file.^{(334.3KB, hkl)}

Structure factors: contains datablock(s) I. DOI: 10.1107/S1600536813001888/fy2080Isup2.hkl

e-69-0o328-Isup2.hkl^{(334.3KB, hkl)}

Click here for additional data file.^{(8.8KB, cml)}

Supplementary material file. DOI: 10.1107/S1600536813001888/fy2080Isup3.cml

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

Table 1. Halogen and hydrogen-bonding contacts (Å, °).

C—X⋯Y	X⋯Y	C—X⋯Y
C1—I1⋯N1	2.863 (4)	177.93 (16)
C8—I2⋯N2ⁱ	2.887 (4)	175.39 (16)
C1—F1⋯H9ⁱⁱ	2.60	145.3

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Symmetry codes: (i) = −2 + x, 1 + y, −1 + z; (ii) = −x, 1 − y, 1 − z.

Acknowledgments

GC, PM and GT acknowledge the Fondazione Cariplo (projects 2009–2550 and 2010–1351) for financial support.

supplementary crystallographic information

Comment

Bis-(4-pyridyl)buta-1,3-diine (1) (Allan et al., 1988) has been used as ditopic hydrogen bonding (HB) acceptor in crystal engineering (Nakamura et al., 2003; Curtis et al., 2005) and in transition metals complexes (Badruz Zaman et al., 2001; Maekawa et al., 2000), but it has never been used in halogen bonding (XB) adducts formation. Our group has shown that α,ω-diiodoperfluorocarbons are very good ditopic XB donors, both towards neutral (Fox et al., 2004) and ionic (Metrangolo et al., 2008) electron-donors. As expected, when solutions of (1) and 1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8-hexadecafluoro-1,8-diiodooctane (2), are mixed, the (1)···(2) adduct quickly precipitates (Fig. 1). It forms an infinite one-dimensional and non-covalent polymer through short XBs (Table 1). In our experience, this kind of nearly linear adduct has normally Z' = 1/2, that is, both molecules lie on crystallographic elements of symmetry, more frequently C_i, but also C₂ (see Table 2). Here instead, both molecules are in general position and Z' is 1. The cause of the molecular symmetry breaking is an F···H contact, the only interaction shorter than the sum of the van der Waals radii beside the I···N XBs. (Table 1). As happens in most structures containing perfluorocarbons and hydrocarbons moieties (see for example Fox et al., 2008), the two components segregate and a layered structure is formed (Fig. 2).

Experimental

(1) was synthetized according to Della Ciana & Haim (1984); (2) was from Aldrich. The adduct was obtained by slow evaporation from a 1:1 solution of the two components in chloroform.