Exploring the nitric oxide dioxygenation (NOD) reactions of manganese-peroxo complexes.

Here, we report the nitric oxide dioxygenation (NOD) reactions of two Mn III -peroxo (M III -O 2 2- ) complexes, [(3PYENMe)Mn III (O 2 2- )] + (1) and [(N3PY)Mn III (O 2 2- )] + (2), bearing pentadentate ligands. Complexes 1 and 2 give Mn II -nitrate (Mn II -NO 3 - ) complexes (3 and 4) when reacted with nitric oxide (NO), respectively. The mechanistic study explored by using 2,4-di- tert -butylphenol (2,4-DTBP) suggested that the NOD reaction of 1 and 2 occurs via a presumed Mn-peroxynitrite ([Mn-PN] + , [Mn-ONOO - ] + ) intermediate. Tracking the source of N atoms using 15 NO revealed that the N-atoms in Mn II -NO 3 - (3 and 4) are derived from the 15 NO moiety. Furthermore, we have explored the M III -O 2 2- regeneration from NOD products (3 and 4), and we have observed the formation of M III -O 2 2- complexes (1 and 2) upon treatment with KO 2 or H 2 O 2 /triethylamine (TEA), respectively.