Reductive Amination of 5-Formyl-2-furancarboxylic Acid and its Dimethylacetal Form to 5-Aminomethylfuran-2-carboxylic Acid over a Cobalt Phosphide Nanorod Catalyst

Abstract

The reductive amination of 5-formylfuran-2-carboxylic acid (FFCA) and its dimethylacetal form (FFCA-acetal) was studied with a cobalt phosphide nanorod catalyst to yield 5-aminomethylfuran carboxylic acid (AMFCA) which can be potentially used as a monomer for biobased polyamides. Under optimized conditions, i.e. 0.5 mmol of FFCA-acetal, 5 mmol of NH₄OAc, substrate to catalyst ratio of 10 mol/mol, under 5 bar H₂ at 393 K for 3 hours in methanol/water 2/1 (v/v), AMFCA was obtained in 91% yield. Kinetic studies suggests that the reaction route via the hemiacetal form of FFCA-acetal is the key for efficient AMFCA formation.