Development of a catalytic process for isomerization of D-glucose into D-fructose presents a crucial step for valorization of lignocellulosic feedstocks. This review focuses on basic catalysts as highly catalytically active and readily commercially available molecules and materials. The recent publications report that the solid bases catalyze the isomerization mainly heterogeneously with only a minor contribution of catalysis by OH−. For catalysis by amines, the hydroxide ions are on the contrary believed to be catalytically active species, though selectivity for d-fructose seems to depend on the amine structure. Buffers present another type of soluble basic catalysts which can be readily coupled with a facile separation of d-fructose from the reaction mixture via anionic extraction or adsorption upon complexation with phenylboronic acids.
