Trifluoroacetic acid → Trifluoroacetic acid

Participants

Reaction Steps

(step 5) 2.37 g (4.3 mmol) (2S,4R)-2-[N′-Methyl-N′-(4-methyl-phenylsulfonyl)-hydrazinocarbonyl]-4-(4-methoxy-benzylsulfanyl)-pyrrolidine-1-carboxylic acid 1-tert-butyl ester in 10 ml CH2Cl2 were treated with 4 ml TFA at 0° C. and kept in the freezer over night. The solvent was evaporated, the crude material was dissolved and evaporated with toluene (2×) and hexane (3×) yielding (2S,4R)-2-[N′-Methyl-N′-(4-methyl-phenylsulfonyl)-hydrazinocarbonyl]-4-(4-methoxy-benzylsulfanyl)-pyrrolidine as TFA salt as crude product, which was subjected to the following reaction without further purification.

Provenance & Evidence