p-Toluenesulfonic acid monohydrate → tetrahydro-3-hydroxy-(R)-6-undecyl-2H-pyran-2-one

Participants

Reaction Steps

M)a) 15.4 g of a diastereomer mixture of 2-hexyl-3-hydroxy-(R)-5-[(tetrahydro-2H-pyran-2-yl)oxy]hexadecanoic acid were dissolved in 160 ml of ethanol and 800 mg of toluene-4-sulfonic acid monohydrate were added. The reaction mixture was heated to 55°-60° C. until the reaction was finished. The solvent was removed in vacuo and the residue was dissolved in 160 ml of dichloromethane. The solution was stirred at room temperature for 1 hour. The reaction mixture was evaporated. The material obtained was chromatographed on silica gel. There was obtained tetrahydro-3-hydroxy-(R)-6-undecyl-2H-pyran-2-one, m.p. 95°-96° C.

Provenance & Evidence