Methanol → HCID 67764943, compound

Participants

Reaction Steps

An argon flushed solution of this phenylmethyl ester product (0.71 g., 1.2 mmole) in 95% ethanol (30 ml.) is treated with 10% palladium on carbon catalyst (70 mg.). The mixture is hydrogenated under a positive pressure of hydrogen, with thorough stirring, overnight at room temperature. After filtering the mixture through Celite, the filtrate is concentrated in vacuo to give 0.41 g. of a light brown solid. An analytical sample is prepared by recrystallization of 0.33 g. from ethyl acetate/hexane to yield 0.243 g. of white solid (trans)(R,R)-N-[N-[N-[(2-carboxycyclohexyl)carbonyl]-L-phenylalanyl]-L-leucine; m.p. 183.5°-185°. [α]D =39.8° (C =1.0, methanol). TLC (silica gel; toluene:acetic acid, 9:2) Rf =0.30.

Provenance & Evidence