Rhodium complexes dioxygen activation

Hydroperoxo complexes can also be obtained by a one-electron reduction of the superoxo intermediates [Ru(NH3)6]2 + is one of the most convenient reducing agents for this chemistry.15 An interesting way of preparing hydroperoxides via dioxygen activation utilizes a formal 02 insertion into M-H bond in metal hydrides examples are known for platinum, rhodium, and cobalt complexes, to name just a few.14,15... 

The investigation of phosphine complexes of rhodium(I) as catalysts (or catalyst precursors) for the hydroformylation reaction continues both to better elucidate the reaction mechanism and to improve catalyst activity. The presence of dioxygen often decreases the catalytic activity (139), but can also, surprisingly, reactivate hydroformylation catalysts... 

To explain the observed behavior, it has been suggested [163,164,169,171] that the oxidation of terminal olefins to methyl ketones takes place via two complementary reactions occurring in a coupled mode (Scheme 12). These reactions are the activation of dioxygen (path A) and a Wacker type oxidation (path B). In path A, the cationic rhodium(II) complex 17, formed from RhCl, olefin, EtOH and... 

The oxidation of terminal olefins to ketones with dioxygen is catalyzed by rhodium(I) phosphine complexes. The phosphine is co-oxidized to the phosphine oxide. Mechanistic studies show that the active intermediate contains a ir-bonded olefin and dioxygen is... 

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