Mono- and dinuclear osmium N,N′-di- and tetraphenylbipyridyls and extended bipyridyls. Synthesis, structure and electrochemistry

Abstract

The efficient synthesis of mono- and dinuclear Os(IV) bipyridyl complexes is reported. These compounds show a two-step oxidation process leading to notable structural changes, which are reflected in their emission properties. During the second oxidation process a tetracation with a hydride-dihydrogen structure (instead of a trihydride) is formed. This results in a significant bathochromic shift of the emission band, accompanied by a moderate increase in intensity.