A Cooperative Rh/Co‐Catalyzed Hydroaminomethylation Reaction for the Synthesis of Terpene Amines

Abstract

AbstractAn original bimetallic catalytic system based on Rh(I) and Co(0) in glycerol is described for the synthesis of biomass‐derived amines through the tandem hydroaminomethylation reaction of terpenes, such as (R)‐limonene, β‐pinene and camphene. Under optimized conditions, this multicatalytic system is highly chemoselective (avoiding hydrogenations of substrates and aldehyde‐based intermediates, and aldol condensations), exhibiting good‐to‐excellent regioselectivity towards linear amines. From a mechanistic viewpoint, cobalt mainly boosts the reductive amination, while rhodium shows a foremost role in the hydroformylation step. Regarding the nature of the organometallic species, catalytically inactive metal nanoparticles have been identified at the end of the reaction, proving the homogeneous nature of the bimetallic catalytic system.