ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

The determination of D-erythro-2-pentulose in the presence of B-arabinose and D-ribose

M. Fedoroňko and K. Linek

Slovak Academy of Sciences, Bratislava

Abstract: On the basis of kinetics in the formation of the furfural, the conditions for the spectrophotometric and polarographic detns. of D-erythro-2-pentulose (I) in a mixt. with D-arabinose (H) and D-ribose (III) were described. The speed of formation of furfural or 5-hydroxymethyl furfural from the pentoses or hexoses, resp., in aq. solutions of mineral acids is dependent not only on the reaction conditions but also on the type of monosaccharide. I in 0.4N H₂SO₄ at 100° is dehydrated to furfural much faster than II and III. This is a 1st-order reaction. The velocity const. for the formation of furfural is 1.4 × 10^-2 1./mole/min. The optimum conditions for the anal. detn. are heating the mixt. in 0.4N H₂SO₄ on the waterbath for 15 min. Furfural formed from I is detd. directly spectrophotometrically at 278 mμ or by the polarographic method with borate buffer, pH 9.3. The method can be used in the concn. range 20-500 γ/ml. if I is alone and in the concn. range 70-500 γ/ml. in the mixt.

Full paper in Portable Document Format: 197a550.pdf (in Slovak)

Chemical Papers 19 (7) 550–558 (1965)