CO2 Fixation and Catalytic Reduction by a Neutral Aluminum Double Bond.

CO2 fixation and reduction to value-added products is of utmost importance in the battle against rising CO2 levels in the Earth's atmosphere. An organoaluminum complex containing a formal aluminum double bond (dialumene), and thus an alkene equivalent, was used for the fixation and reduction of CO2 . The CO2 fixation complex undergoes further reactivity in either the absence or presence of additional CO2 , resulting in the first dialuminum carbonyl and carbonate complexes, respectively. Dialumene (1) can also be used in the catalytic reduction of CO2 , providing selective formation of a formic acid equivalent via the dialuminum carbonate complex rather than a conventional aluminum-hydride-based cycle. Not only are the CO2 reduction products of interest for C1 added value products, but the organoaluminum complexes isolated represent a significant step forward in the isolation of reactive intermediates proposed in many industrially relevant catalytic processes.