Small molecule activation with divalent samarium triflate: a synergistic effort to cleave O₂

The divalent samarium triflate salt does not react with CO₂ or water, but does react with traces of O₂ or N₂O to form a tetrameric bis-oxo samarium motif. The reaction with O₂ is a 4e^- reductive cleavage where the electrons are coming from four different samarium centers. This highlights a rare synergistic effect for cleaving O₂, which has no precedent in divalent lanthanide complexes. Additionally, the addition of CO₂ to the tetrameric bis-oxo intermediate leads to the formation of a tetrameric bis-carbonate samarium triflate. Thus, the concomitant reaction of CO₂ with traces of O₂ leads to the same bis-carbonate tetrameric assembly.