Reductive Amination of 5-Hydroxymethylfurfural by the Hydrogenation of Intermediate Imines in the Presence of a Pt/Al2O3 Catalyst in a Flow Reactor

The catalytic properties of a platinum catalyst supported on gamma-alumina in the hydrogenation of imines formed during the condensation of 5-hydroxymethylfurfural (HMF) with primary amines in methanol have been studied. The reaction has been run in a flow reactor at a hydrogen pressure of 5 bar and a temperature of 15-65oC. It has been found that the reductive amination of HMF with n-hexylamine; aniline; ortho-, meta-, and para-toluidines; and aniline derivatives containing F, Cl, Br, and I substituents at the para- or meta-positions leads to the formation of N-substituted 5-hydroxymethyl-2-furfuryl amines with high yields (90-99%). At the same time, the reaction of HMF with aromatic amines exhibiting weak nucleophilic properties (o-chloroaniline, p-aminoacetophenone) provides a target product yield that does not exceed 52%. [GRAPHICS] .