D-(-)-Fructose → 5-Acetoxymethyl-2-furaldehyde

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

39.4 kg (219 mol) of D-fructose and 5.9 kg of dried acidic Dowex® 50WX8-200 ion exchanger (styrene-divinylbenzene copolymer resin with SO3H groups, obtainable from The Dow Chemical Company, Midland, U.S.A.) in the H form were introduced with stirring into 90 l of NMP and heated to 110° C. for 6 h. After cooling, the reaction mixture was filtered and washed with 8 l of NMP. The filtrate was admixed with stirring with 390 g (3.2 mol) of 4-(N,N-dimethylamino)pyridine and 20.5 1 (217 mol) of acetic anhydride at 20-25° C. within 1 h. After continuing the reaction for 1 h, the brown reaction mixture was freed of the solvent at 90-100° C. under reduced pressure (of 50-10 mbar). After cooling, the residue was admixed with 160 l of MtBE, 60 1 of water and 4 kg of activated carbon. The suspension was filtered though Celite®. After the phase separation, the solvent of the filtrate was distilled off at 50° C. under reduced pressure (20 mbar) and the residue was fractionally distilled under reduced pressure at 106-110° C./5 mbar.

Herkunft & Nachweise