Hydrochloric Acid → (5S)-5-phenyloxolan-2-one

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

In a 100 ml autoclave were charged 1.78 g (10 mmole) of 4-phenyl-4oxobutyric acid and 14 ml of ethanol. A solution separately prepared from 44.9 mg (0.05 mmole) of ##STR13## double the molar quantity of concentrated hydrochloric acid, and 5 ml of ethanol was added to the above-prepared solution in a nitrogen atmosphere to conduct hydrogenation at 35° C. and at a hydrogen pressure of 70 kg/cm2 for 230 hours. To the reaction mixture was added 8 ml of a 10% sodium hydroxide aqueous solution, followed by stirring at 40° C. for 3 hours. After cooling to room temperature, the resulting solution was extracted twice with 30 ml portions of methylene chloride. The organic layer was removed, and the aqueous layer was adjusted to a pH of 4 with a 10% hydrochloric acid aqueous solution and then again extracted thrice with 20 ml portions of methylene chloride. The combined extract was concentrated, and the residue was purified by silica gel column chromatography using hexanediethyl ether as a developing solvent to obtain 1.02 g (percent yield: 63%) of (S)-4-phenyl-γ-butyrolactone.

Herkunft & Nachweise