Tandem Hydroformylation/Acyloin Reaction - The Synergy of Metal Catalysis and Organocatalysis Yielding Acyloins Directly from Olefins

A novel, atom efficient, orthogonal tandem catalysis was developed yielding acyloin products (α‐hydroxy ketones) directly from olefins under hydroformylation conditions. The combination of a metal‐catalysed hydroformylation and an organocatalysed acyloin reaction provides three atom efficient CC bond formations to linear, multifunctional molecules via linkage of the intermediate n‐aldehydes. Additionally, the rhodium catalyst system gives a high n/bra ratio with an exclusive conversion of the terminal double bond in the hydroformylation and the n‐aldehydes are converted selectively to their acyloins.