Methylglyoxal → 3,4-Dihydroxy-2,5-hexanedione

Participants

Reaction Steps

A solution of methyl glyoxal 40% wt in water (9 g, 50 mmoles), zinc acetate (0.44 g) and hydroxy-acetone (7.4 g) in ethyl acetate (20 ml) were stirred during 40 h at 38/40° (pH of the reaction medium was around 4.5). At the end of the reaction (which can be checked by gas chromatography), the reaction mixture was extracted with ethyl acetate (3×50 ml). The organic phase was washed to neutral with brine (1×), dried over magnesium sulphate and concentrated under vacuum giving 6 g of the crude 3,4-dihydroxyhexane-2,5-dione who was Bulb-to-bulb distilled at 0.1 mbar and 120-150° to obtain 3.8 g of a mixture of the two 3,4-dihydroxyhexane-2,5-dione isomers.

Provenance & Evidence