Hydrochloric Acid → 5-(2,2-dimethyl-1,3-dioxolan-4-yl)-3,4-dihydroxy-2(5H)-furanone

Participants

Reaction Steps

In a 12-L round bottom flask was placed 8,000 mL acetone, 1,600 g L-ascorbic acid, 1,880 mL 2,2-dimethoxypropane and the mixture was stirred for 1/4 hr; hydrogen chloride was added slowly through bubbler over 2-4 min (color of solution changed from colorless to dark yellow). The mixture was stirred for 1 hr and became very viscous. The product was filtered, washed with cold acetone and the solid was then air dried in hood to give 1,521 g of 1st crop of 5,6-O-isopropylidene-L-ascorbic acid. The mother liquor was concentrated to give 225 g of 2nd crop and 162 g of 3rd crop of 5,6-O-isopropylidene-L-ascorbic acid.

Provenance & Evidence