Anion-directed organized assemblies of protonated pyrazole-based ionic salts

The reactions of 3(5)-(4-methoxyphenyl)-5(3)-phenyl-1H-pyrazole (L (1) ) with nitric acid and 5-(4-benzyloxyphenyl)-3-(furan-2-yl)-1H-pyrazole(L (2) ) with hydrochloric acid produced [HL (1) center dot NO3] (Salt-1) and [HL (2) center dot Cl] (Salt-2). The structures of Salt-1 and Salt-2 were determined by single crystal X-diffraction. In Salt-1, HL (1) showed [2 + 2] binding of NO3 (-) ions in the solid state to form dimer architecture with R (1) (2) (4) and R (4) (4) (14) graph sets. An anion directed one-dimensional anion-assisted helical chain with active participation of the chloride ion and protonated pyrazole via N-H center dot center dot center dot Cl hydrogen bonding in Salt-2. In addition, the protonated HL (2) molecules interacted with each other through weak C-H center dot center dot center dot pi interactions resulting in the formation of another one-dimensional helical chain.