The pentafluoropyridyl complex [Rh(4-C5NF4)(PEt3)3] (3) reacts with H2 to give initially the dihydrido complex cis-mer-[Rh(H)2(4-C5NF4)(PEt3)3] (6). Within a few hours 2,3,5,6-tetrafluoropyridine as well as two rhodium(III) complexes mer-[Rh(H)3(PEt3)3] (mer-) and fac-[Rh(H)3(PEt3)3] (fac-) are formed. A catalytic C-F activation process for the formation of 2,3,5,6-tetrafluoropyridine starting from pentafluoropyridine and dihydrogen using 3 as a catalyst has been developed. Reaction of [RhH(PEt3)3] (1) with hydrogen affords fac-[Rh(H)3(PEt3)3] (fac-7) and mer-[Rh(H)3(PEt3)3] (mer-7) in a ratio of 1 : 7.25 at 193 K. The latter complex represents the first mononuclear rhodium compound bearing trans-hydrides.

„Aus der Luft gegriffen“ wird molekularer Sauerstoff bei rhodiumvermittelten Umwandlungen zu Wasserstoffperoxid, Bis(trimethylsilyl)peroxid und Methylhydroperoxid. Intermediäre η1‐Hydroperoxo‐, η1‐Silylperoxo‐ und η1‐Methylperoxo‐Verbindungen konnten isoliert werden. Ein weiterer η1‐Methylperoxo‐Komplex (siehe Bild) und ein η1‐Hydroperoxo‐Komplex wurden durch Röntgenstrukturanalyse charakterisiert.

Out of thin air, a rhodium complex converts molecular oxygen into hydrogen peroxide, bis(trimethylsilyl) peroxide, and methyl hydroperoxide. Intermediate η1‐hydroperoxo and η1‐silylperoxo, and η1‐methylperoxo complexes have been isolated. Another η1‐methylperoxo (see picture) and an η1‐hydroperoxo complex have been characterized by X‐ray crystallography.

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Heterocyclic peroxides with a five‐membered RhOOBO ring have been isolated by reaction of a rhodium peroxo complex with phenylboronic acids. They can be considered to be rhodium derivatives of perboric acid (see scheme) and phenylperboronic acids.