Decarbonylative Olefination of Aldehydes to Alkenes

New atom-economical alternatives to Wittig chemistry are needed construct olefins from carbonyl complexes, but none have been developed to-date. Here we report an atom-economical olefination of carbonyls via aldol-decarbonylative coupling of aldehydes using robust and recyclable supported Pd catalysts, producing only CO and H₂O as waste. The reaction accommodates homocoupling of aldehydes with an a a-methylene groups, as well as heterocoupling. Computations provide insight into the selectivity of the reaction. The tandem aldol-decarbonylation reaction opens the door to exploration of new carbonyl reactivity to construct olefins.