Furfurylamines from biomass: transaminase catalysed upgrading of furfurals
Furfural is recognised as an attractive platform molecule for the production of solvents, plastics, resins and fuel additives. Furfurylamines have many applications as monomers in biopolymer synthesis and for the preparation of pharmacologically active compounds, although preparation via traditional synthetic routes is not straightforward due to by-product formation and sensitivity of the furan ring to reductive conditions. In this work transaminases (TAms) have been investigated as a mild sustainable method for the amination of furfural and derivatives to access furfurylamines. Preliminary screening with a recently reported colorimetric assay highlighted that a range of furfurals were readily accepted by several transaminases and the use of different amine donors was then investigated. Multistep synthetic routes were required to synthesise furfurylamine derivatives for use as analytical standards, highlighting the benefits of using a one step biocatalytic route. To demonstrate the potential of using TAms for the production of furfurals, the amination of selected compounds was then investigated on a preparative scale.