Synthesis, crystal structure, and Hirshfeld surface analysis of 3-ferrocenyl-1-(pyridin-2-yl)-1-pyrazol-5-amine.

A key step towards utilizing polynuclear metal-based systems in magnetic device applications involves the careful design of ligands. This strategic planning aims to produce metal assemblies that exhibit some kind of 'switch' mechanism. Towards this end, a ligand that incorporates a redox-active functional group (ferrocene) is reported.

Structures, Phase Behavior, and Fluorescent Properties of 3-Phenyl-1-(pyridin-2-yl)-1-pyrazol-5-amine and Its ZnCl Complex.

The synthesis of the asymmetric ligand 3-phenyl-1-(pyridin-2-yl)-1-pyrazol-5-amine () and its single-crystal X-ray structure are reported. displays crystallographic symmetry (orthorhombic, ) higher than its molecular symmetry (point group ) and also displays supercooling, with a difference in the melting and solidification points of over 100 °C. Upon complexation with ZnCl, engages in both primary cation and secondary anion coordination via hydrogen bonding, and the complex exhibits a room-to-low-temperature single crystal-to-crystal phase transition.