Hydroquinone → Pidobenzone

Participants

Reaction Steps

129 g (1 mol) of (l)-pyroglutamic acid and 110 g (1 mol) of hydroquinone are intimately mixed, the mixture is stirred at 175° under a stream of nitrogen for 18 hours, the temperature is lowered to 50° and the mixture is diluted with water (300 ml) and extracted with ethyl acetate (3×400 ml). A crude product is thus prepared which is purified by being made into a paste twice with ethyl acetate (250 ml) to give the title derivative in the form of crystals melting at 179°/82°. In TLC, the product shows a single spot of Rf(i)=0.33.

Provenance & Evidence