Hydrogen-bonding chain and dimer motifs in pyridinium and morpholinium hydrogen oxalate salts

Abstract

We present here three compounds consisting of pyridinium or morpholinium hydrogen oxalates, each displaying different hydrogen-bonding motifs, resulting in chains for 4-(di-methyl-amino)-pyridinium hydrogen oxalate 0.22-hydrate, C₇H₁₁N₂ ⁺·C₂HO₄ ^-·0.22H₂O (1), dimers for 4-tert-butyl-pyridinium hydrogen oxalate, C₉H₁₄N⁺·C₂HO₄ ^- (2), and chains for morpholin-ium hydrogen oxalate, C₄H₁₀NO⁺·C₂HO₄ ^- (3).

Keywords: ammonium cations; crystal structure; hydrogen bonding; oxalate.