C–H⋯O or N–H⋯O hydrogen bonded biomimetic dimerized rectangular secondary structural motifs formed by L-shaped fatty acid-substituted nicotinamide salts with PF6−, BF4−, NO3− and Br− anions

Abstract

A series of 3-carbamoyl-1-(10-carboxydecyl)pyridin-1-ium salts with four anions (PF₆⁻ (1), BF₄⁻ (2), NO₃⁻ (3), and Br⁻ (4)) have been synthesized and characterized by single-crystal X-ray diffraction. All four salts have a primary L-shaped cation conformation, and each pair of cations forms a similar well-defined rectangular motif of nicotinamide cations and fatty acid groups via N–H⋯O or C–H⋯O hydrogen bonding. The effects on hydrogen-bonding motifs, building blocks and structures of the four anion species with different hydrogen-bonding acceptor abilities, sizes and shapes are discussed.