“…Alternatively, transition metal carbon dioxide complexes can react with dioxygen [3,4] to afford peroxocarbonates. (1) By using labelled species, we have recently shown that CO 2 reacts with Rh(η 2 -O 2 ) complexes by insertion into the OϪO bond (Scheme 1, path A), rather than by insertion into the MϪO bond (Scheme 1, path B). [5] The reaction pathway has been demonstrated through coupling an IR theoretical study (calculation of the vibrational frequencies of selected bonds of the peroxocarbonate complexes) with experimental vibrational frequencies.…”