Hydrochloric Acid → 2-Hydroxy-6-(hydroxymethyl)-4h-pyran-4-one

Temperatur

50 °C

6-Bromomethyl-4-hydroxypyran-2-one (21.1 parts) was dissolved in a solution of sodium hydroxide (4.1 parts) in water (800 parts) at 20°-25° C. This solution was added over about 2 hours to a solution of sodium hydroxide (34.2 parts) in water (3200 parts) at 50° C.±3° C. The mixture was stirred for a further hour at 50° C. before acidifying with 35% hydrochloric acid and distilling off the bulk of the water at 50° C./20 mm. The mixture was cooled to 20° C. and insoluble material was filtered off. The filtrate was saturated with sodium chloride and then extracted with ethyl acetate (15×125 parts). The combined extracts were dried over magnesium sulphate and the solvent removed at 40° C./20 mm to give 4-hydroxy-6-hydroxymethylpyran-2-one (10.2 parts, 69%).

1. distillationdistilling off the bulk of the water at 50° C./20 mm
2. temperatureThe mixture was cooled to 20° C.
3. filtrationinsoluble material was filtered off
4. extractionextracted with ethyl acetate (15×125 parts)
5. dry with materialThe combined extracts were dried over magnesium sulphate
6. customthe solvent removed at 40° C./20 mm

ORD-Eintrag

ord-111d9c490bd64c338a63bca79d24b43f

Quelldatensatz

uspto-grants-1995_08

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US05443970