Elaboration and physicochemical elucidation of two organic cation hydrogensulfates: 2-Fluroanilinium (hydrogensulfate) monohydrate (I) and 2,6-dimethylanilinium (hydrogensulfate) monohydrate (II)

(C6H4NH3F)(HSO4)center dot H2O (I) and (C8H12N)(HSO4)center dot H2O (II) have been prepared by reaction of 2-fluoroaniline and 2,6-dimethylaniline, respectively, with acidic aqueous solution at room temperature. Molecular structures of these compounds were determined by single crystal X-ray diffraction analysis. Both sulfates crystallize in the monoclinic space group P2(1)/c with Z=4. In both structures organic and inorganic (anion and H2O) moieties are separately stacked to form alternating layers parallel to the (a,c) plane in (I) and to the (b,c) plane in (II). The anionic and cationic layers are linked through N-H center dot center dot center dot O hydrogen bonds involving the aniline NH3+ groups. The enrichment ratio from the Hirshfeld surface analysis was used to investigate which kind of contacts is over-or under-represented in the crystal packing. These two new salts were also characterized by solid-state C-13 CP-MAS NMR spectroscopy and by infrared spectroscopy. NMR peaks were attributed with the help of DFT calculations. Moreover, electronic properties such as HOMO and LUMO energies were determined. (C) 2020 Elsevier B.V. All rights reserved.

Automated summary

Two new salts were prepared and their molecular structures were determined by single crystal X-ray diffraction analysis. The crystal packing contacts were investigated using the enrichment ratio from the Hirshfeld surface analysis. The salts were also characterized by solid-state NMR and infrared spectroscopy.