Supramolecular Arrays of Cationic Complexes Containing Pyrazole Ligands and Tetrafluoroborate, Trifluoromethanesulfonate, or Nitrate as Counterions. Crystal Structure of Bis(3,5‐dimethyl‐4‐nitro‐1H‐pyrazole‐κN2)silver(1+) Nitrate ([Ag(HpzNO2)2](NO3))

Abstract

AbstractThe structures of [Pd(η3‐C3H5)(HpzR2)2](BF4) (HpzR2=Hpzbp2=3,5‐bis(4‐butoxyphenyl)‐1H‐pyrazole, 1; HpzR2=HpzNO2=3,5‐dimethyl‐4‐nitro‐1H‐pyrazole=Hdmnpz, 2) and [Ag(HpzR2)2](A) (HpzR2=Hpzbp2, A=$\rm{ BF_4^ -}$, 3; HpzR2=HpzNO2, A=$\rm{ CF_3 SO_3^ -}$, 4) were comparatively analyzed to determine the factors responsible for polymeric assemblies. In all cases, the H‐bonding interactions between the pyrazole moieties and the appropriate counterion and, in particular, the orientation of the NH groups of the pyrazole ligands are determinant of one‐dimensional polymeric arrays. In this context, the new compound [Ag(HpzNO2)2](NO3) (5) was synthesized and its structure analyzed by X‐ray diffraction (Fig. 4). The HpzNO2 serves as N‐monodentate ligand, which coordinates to the AgI center through its pyrazole N‐atom giving rise to an almost linear NAgN geometry. The planar NO$\rm{_{3}^{-}}$ counterion bridges two adjacent AgI centers to form a one‐dimensional zigzag‐shaped chain which is also supported by the presence of NH⋅⋅⋅O bonds between the pyrazole NH group of adjacent cationic entities and the remaining O‐atom of the bridging NO$\rm{_{3}^{-}}$ (Fig. 5). The chains are further extended to a two‐dimensional layer‐like structure through additional Ag⋅⋅⋅O interactions involving the NO2 substituents at the pyrazole ligands (Fig. 6).