D-(-)-Fructose → Naphthalene

Participants

Reaction Conditions

Reaction Steps

A 50 ml autoclave (Microclave reactor from Autoclave Engineers) was charged with 250 mg glucose, 150 mg of one of the catalysts: HY 2.6, HY 6, HY 30, Hbeta 12.5, Hbeta 19, Hbeta 150, and HZSM-5 (purchased from Zeolyst International, USA) and 10 mL solvent (methanol, ethanol, propanol or butanol) and then pressurized with argon (20 bar). The autoclave was heated to 160° C. and the stirring was started at 300 rpm once the temperature reached 150° C. After 20 hours of stirring, the autoclave was quenched with cold water and 50 mg naphthalene (internal standard) added to the reaction mixture and the content thereafter analyzed. Aliquots of the reaction mixtures were subjected to GC-FID analysis (Agilent 6890N instrument, HP-5 capillary column 30.0 m×320 μm×0.25 μm). The reaction mixtures were also analyzed by HPLC with RI detection (Agilent 1200 series, 30 cm Aminex© HPX-87H column, 0.005 M aqueous sulfuric acid solution as eluent at a flow rate of 0.6 ml/min). An Agilent 6850 GC system coupled with an Agilent 5975C mass detector was used for qualitative analysis. Sugar conversions to levulinic acid esters were determined by HPLC. The amounts of unreacted monosaccharides were calculated from their individual HPLC standards. Sucrose inverts to fructose and glucose on the acidic HPLC-column used, and the conversions were calculated from the monosaccharides fructose, glucose and mannose on a carbon-basis. The yield of levulinate esters were calculated from GC results on series of individual levulinate ester standards with naphthalene as internal standard. The results are shown in Tables 3 and 7.

Provenance & Evidence