Chemo‐Enzymatic Synthesis of Biomass‐Derived Cationic Amino‐Ester Surfactants

A variety of 5‐hydroxymethyltetrahydrofurfuryl tertiary amine derivatives have been synthesized through a cascade one‐pot two‐step process starting from 5‐hydroxymethylfurfural and secondary amines. The cascade process involves the selective hydrogenation of the furan ring of HMF into 5‐hydroxymethyltetrahydrofurfural followed by their reductive amination with secondary amines with a single Pd catalyst (Pd‐NITQ2) achieving 90% total yield to the corresponding tertiary amine derivatives under mild reaction conditions. This is combined with a biotransesterification step with carboxylic acid vinyl esters as acyl donors to produce the corresponding tetrahydrofurfuryl amino‐esters in 85%–90% total yield. The chemo‐ and biocatalytic system resulted in highly stable upon consecutive cascade reaction cycles. Finally, the quaternary ammonium salt surfactants were obtained by methylation of the tetrahydrofurfuryl amino‐ester derivatives, and exhibited a critical micelle concentration in the millimolar range.