Viger-Gravel Jasmine, Korobkov Ilia, Bryce David L
Department of Chemistry, University of Ottawa, D'Iorio Hall, 10 Marie Curie Private, Ottawa, Ontario, K1N 6N5, Canada.
Acta Crystallogr E Crystallogr Commun. 2015 Apr 9;71(Pt 5):o286-7. doi: 10.1107/S2056989015006593. eCollection 2015 May 1.
The crystallization of a 1:1 molar solution of 1,2-di-iodo-3,4,5,6-tetra-fluoro-benzene (o-DITFB) and tetra-butyl-ammonium bromide (n-Bu4NBr) from di-chloro-methane yielded pure white crystals of a halogen-bonded compound, C16H36N(+)·Br(-)·C6F4I2·0.5CH2Cl2 or [(n-Bu4NBr)(o-DITFB)]·0.5CH2Cl2. The compound may be described as a quaternary system and may be classified as a salt-cocrystal solvate. The asymmetric unit contains one mol-ecule of solvent, two o-DITFB mol-ecules, two cations (n-Bu4N(+)) and two crystallographically distinct bromide ions [θI ⋯ Br- ⋯ I = 144.18 (1) and 135.35 (1)°]. The bromide ion is a bidentate halogen-bond acceptor which inter-acts with two covalently bonded iodines (i.e. halogen-bond donors), resulting in a one-dimensional polymeric zigzag chain network approximately along the a axis. The observed short contacts and angles are characteristic of the non-covalent inter-action [d C-I⋯Br = 3.1593 (4)-3.2590 (5) Å; θC-I⋯Br = 174.89 (7) and 178.16 (7)°]. It is noted that iodine acts as both a halogen-bond donor and a weak CH hydrogen-bond acceptor, while the bromide ions act as acceptors for weak CH hydrogen bonds and halogen bonds.
1,2 - 二碘 - 3,4,5,6 - 四氟苯（邻二碘四氟苯，o - DITFB）与四丁基溴化铵（n - Bu₄NBr）的1:1摩尔溶液在二氯甲烷中结晶，得到了一种卤键化合物的纯白色晶体，即C₁₆H₃₆N⁺·Br⁻·C₆F₄I₂·0.5CH₂Cl₂ 或[(n - Bu₄NBr)(o - DITFB)]·0.5CH₂Cl₂。该化合物可描述为一个四元体系，可归类为盐 - 共晶溶剂化物。不对称单元包含一个溶剂分子、两个o - DITFB分子、两个阳离子（n - Bu₄N⁺）和两个晶体学上不同的溴离子[θI⋯Br⁻⋯I = 144.18 (1) 和135.35 (1)°]。溴离子是一个双齿卤键受体，它与两个共价键合的碘（即卤键供体）相互作用，形成了一个大致沿a轴的一维聚合锯齿链网络。观察到的短接触和角度是非共价相互作用的特征[d C - I⋯Br = 3.1593 (4) - 3.2590 (5) Å；θC - I⋯Br = 174.89 (7) 和178.16 (7)°]。值得注意的是，碘既作为卤键供体又作为弱CH氢键受体，而溴离子则作为弱CH氢键和卤键的受体。
