process for extraction of d (-) - pantolacton from fdi pantolacton

摘要

1,183,387. Pantolactone. DELMAR CHEMICALS Ltd. 23 May, 1967 [19 July, 1966], No. 23962/67. Heading C2C. D(-)-pantolactone , is prepared by reacting DL-pantolactone with an alkali metal hydroxide to form an alkali metal salt, contacting with an acid salt of dehydroabietylamine in a solvent, separating the precipitated crystalline dehydroabietylamine salt of L(+)-α,γ-dihydroxy-#,#- dimethyl-butyric acid, treating the mother liquor containing the dehydroabietylamine salt of D(-) - α,γ - dihydroxy - #,# - dimethylbutyric acid with a base, separating the freed dehydroabietylamine, acidifying the mother liquor and heating to reflux the acidified mother liquor containing pantoic acid and isolating the - D(-)-pantolactone.