(R)-3-phenyllactic acid → (αR)-α-Hydroxycyclohexanepropanoic acid

Participants

Reaction Steps

5 g (30.1 mmole) of 3-phenyl-D-lactic acid [Rf (2)=0.45-0.55] is dissolved in 70 ml of acetic acid and submitted to hydrogenation in the presence of 0.25 g of platinum(IV)oxide catalyst in the temperature range of 40° to 50° C. The reaction is monitored by thin-layer chromatography [final product: Rf (2)=0.6-0.7]. After completed reaction the catalyst is filtered off, the filtrate is evaporated from a water bath at a temperature not higher than 40° C., at 20-25 millibar. Then 20 ml of toluene is evaporated twice from the residue which is finally recrystallized from n-hexane.

Provenance & Evidence