A hydroaminomethylation/hydrohydroxymethylation sequence for the one pot synthesis of aminohydroxytriglycerides†
In this paper we report the one pot functionalization of the carbon–carbon double bonds of triglycerides via a cascade hydroaminomethylation (HAM)/hydrohydroxymethylation (HHM) reaction. The carbon–carbon double bonds are first hydroformylated using a Rh-catalyst. The produced aldehydes react with secondary amines to yield enamines which are then reduced to tertiary amines. Interestingly, the latter act as ligands of Rh-species capable of hydrogenating the remaining formyl groups into alcohols. As a result, the final triglycerides are substituted by both aminomethyl and hydroxymethyl groups. Of interest, no phosphane ligand is used to stabilize the Rh-species. Moreover, the proportion of aminomethyl and hydroxymethyl groups grafted onto the triglyceride fatty chains can be finely adjusted by a careful choice of the experimental conditions, especially the nature and the amount of the amine, the reaction temperature, and the CO/H2 pressure. The resulting amino-hydroxylated triglycerides are unprecedented biosourced building blocks whose applications could be of major interest, especially in the field of polymer chemistry.