HCID 20285469, compound → HCID 20285476, compound

Participants

Reaction Steps

Crude N-(3-acetylthio-2-methylpropanoyl)-N-phenylglycine tert-butyl ester (25 g, 0.0712 mol) was dissolved in a mixture of anisole (40 ml) and trifluoroacetic acid (125 ml). The resulting red solution was stirred overnight at room temperature. The solvent was evaporated and the residue was distributed between ethyl acetate and saturated aqueous sodium bicarbonate. The aqueous sodium bicarbonate layer was acidified cautiously with concentrated hydrochloric acid to pH 4-5. The product was extracted several times into chloroform, washed twice with water, and dried over magnesium sulfate. Filtration and evaporation of the extract afforded the crude product as an orange oil which was further purified by HPLC, eluting with ethyl acetate/n-hexane/acetic acid (40:60:1), to afford pure product (7.5 g., 36%) as a pale yellow oil. The product was crystallized from diethyl ether to afford colorless prisms, m.p. 94°-94.5° C.

Provenance & Evidence