Methanol → HCID 13749515, compound

Participants

Reaction Steps

Dissolve 2.59 g 3-(S)-t-butoxycarbonylamino-1-(1-methylcarbonylethyl)perhydroazepin-2-one in 10 ml. methanol and 10 ml water and add 0.5 ml 50% NaOH solution. Store the mixture at room temperature for 2 hours and then concentrate at aspirator pressure to a syrup. Dissolve the syrup in water and chill the solution in an ice bath. Add 6N hydrochloric acid to pH 2 then extract the solution several times with ethyl acetate. Dry the combined extracts over MgSO4, filter and concentrate the filtrate at aspirator pressure and isolate 3-(S)-t-butoxycarbonylamino-1-(1-carboxyethyl)perhydroazepin-2-one as an oil (2.04 g) which is a mixture of diastereomers. Separate the isomers on a column of XAD2 resin at 50° C. using 0.1N NH4OH containing 6% acetonitrile as eluent. Isolate the ammonium salt of the desired isomer as the one which elutes first (u.v. and refractive index detection).

Provenance & Evidence