Synthesis and crystal structure of the pyridinium acid nitrate [(PyH)2(NO3)][H2(NO3)3] containing a dihydrogen trinitrate anion

Abstract

A new protic room-temperature ionic liquid ( T c = 14 ± 1 °C) – pyridinium hydrogen dinitrate – was obtained from a solution of pyridinium nitrate in anhydrous nitric acid in a desiccator with P 2 O 5 . According to single crystal X-ray diffraction data, the solid state structure of [(PyH) 2 (NO 3 )][H 2 (NO 3 ) 3 ] consists of hydrogen bonded cations [(PyH) 2 (NO 3 )] + and anions [(NO 3 )(HNO 3 ) 2 ] − with a previously unknown configuration containing two HNO 3 molecules linked via hydrogen bonds to the central N O 3 − anion by the sin–anti type.