Triethylamine → methyl (2R)-2-[(t-butoxycarbonyl)amino]-4-oxo-4-[4-(9H-thioxanthen-9-ylidene)-1-piperidinyl]butanoate

Participants

Reaction Steps

1.00 g (5.22 mmol) of 1-ethyl-3-(3′-dimethylaminopropyl)carbodiimide hydrochloride, 0.73 ml (5.24 mmol) of triethylamine and 1.351 g (4.84 mmol) of 4-(9H-thioxanthen-9-ylidene)piperidine were added to 1.290 g (5.22 mmol) of (S)-3-[(t-butoxycarbonyl)amino]-4-methoxy-4-oxobutanoic acid in 20 ml of dichloromethane in an ice bath, and they were stirred at room temperature overnight. Saturated aqueous ammonium chloride solution was added to the reaction mixture. After extracting with dichloromethane, the organic layer was dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by the silica gel chromatography (hexane:ethyl acetate=7:3 to 1:1) to obtain the title compound.

Provenance & Evidence