Synthesis and structural studies of half-sandwich Cp* rhodium and Cp* iridium complexes featuring mono, bi and tetradentate nitrogen and oxygen donor ligands

Abstract

A series of Cp*Rh and Cp*Ir complexes of various nitrogen and oxygen donor ligands were synthesized and characterized. Mono, bi and tetradentate ligands were used to synthesize mononuclear and dinuclear complexes. Schiff base derivatives of picolinic hydrazine and 5-aminoquinoline were used in the synthesis of complexes 1-8. Among the ligands used for complexation, L1 and L2 act as bidentate, L3 as monodentate and L4 as tetradentate in forming the corresponding complexes. All the complexes were characterized by spectroscopic techniques and the structures of complexes 2, 3, 5 and 7 were unambiguously characterized by single crystal X-ray crystallography. Complexes 2 and 7 were found to have π-π stacking interactions and solvent to complex interactions, respectively. Metal-mediated deprotonation of N-H and monodentate binding of nitrogen are attributed to the formation of neutral complexes whereas ionic complexes are formed by (N,O) bonding.

Synthesis, structure and bonding modes of pyrazine based ligands of Cp*Rh and Cp*Ir complexes: The study of in-vitro cytotoxicity against human cell lines

“…Recently, our group has reported many half-sandwich platinum group metal complexes containing pyridyl azine ligands [28][29][30][31]. In continuation of our previous work, we report the synthesis of half-sandwich Cp*rhodium and Cp*iridium complexes containing pyrazine based ligands.…”

Two novel metal–organic frameworks functionalised with pentamethylcyclopentadienyl iridium(iii) chloride for catalytic conversion of carbon dioxide to formate

“…2 Platinum group metals are known for their excellent catalytic capabilities; hence, researchers have thoroughly investigated functionalising the bipyridine MOF backbone with these metal complexes. 22,23 In hydrogenation reactions, these metals produce a high yield with outstanding selectivity especially in CO 2 hydrogenation to formate. These metals facilitate H 2 heterolytic fusion, which is a prerequisite step in hydrogenation when using molecular hydrogen.…”

Spectroscopic and electrochemical study for evaluating DNA interaction activity of 4‐(3‐halophenyl)‐6‐(pyridin‐2‐yl)pyrimidin‐2‐amine based piano stool Cp* Rh (III) and Ir (III) complexes

“…In this context, half sandwich organometallic complexes with biological active ligands have been extensively researched for evaluation of their anticancer activities with some of the complexes being clinical evaluated having good cytotoxicity than cisplatin . Recently complexes of rhodium and iridium are getting immense attention as potential therapeutic agents due to their readily tunable reactivity (from kinetically liable to substitutionally inert complexes), high water solubility and relative accessibility.…”