Crystal structure and Hirshfeld surface analysis of supramolecular aggregate of 2,2,6,6-tetramethylpiperidin-1-ium bromide with 1,2,3,4-tetrafluoro-5,6-diiodobenzene

Abstract

The asymmetric unit of the title compound, C9H20N+·Br−·C6F4I2, contains one 2,2,6,6 tetramethylpiperidine-1-ium cation, one 1,2,3,4-tetrafluoro-5,6-diiodobenzene molecule, and one uncoordinated bromide anion. In the crystal, the bromide anions link the 2,2,6,6-tetramethylpiperidine molecules by intermolecular C—H...Br and N—H...Br hydrogen bonds, leading to dimers, with the coplanar 1,2,3,4-tetrafluoro-5,6-diiodobenzene molecules filling the space between them. There is a π–π interaction between the almost parallel benzene rings [dihedral angle = 10.5 (2)°] with a centroid-to-centroid distance of 3.838 (3) Å and slippage of 1.468 Å. No C—H...π(ring) interactions are observed. A Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are from H...F/F...H (23.8%), H...H (22.6%), H...Br/Br...H (17.3%) and H...I/I...H (13.8%) interactions. Hydrogen bonding and van der Waals interactions are the dominant interactions in the crystal packing.

Keywords

• crystal structure
• non-covalent interactions
• halogen bond