Triethylamine → HCID 178470715, compound

Participants

Reaction Steps

To a stirred and cooled suspersion of (S)-Nα -t-butoxycarbonyl-Nω -nitroarginine (3.1 g) in anhydrous tetrahydrofuran (THF) (50 ml) is added triethylamine (0.8 g) dropwise over 5 minutes at -20° C. and stirring is continued for a further 10 minutes. To the stirred mixture is then added isobutyl chloroformate (1.1 g) dropwise over 10 minutes at -20° C. and the mixture is stirred for a further 10 minutes. To the stirred mixture is then added 4-(ethoxycarbonylmethyl)piperidine (1.4 g) in THF (20 ml) dropwise over 10 minutes at -20° C. and then after stirring for a further 10 minutes at -20° the mixture is allowed to warm to room temperature with stirring for 1 hour. The reaction mixture is concentrated by evaporation and the residue is diluted with ethyl acetate (100 ml) and the mixture is washed with portions of water (3×15 ml), aqueous 5% NaHCO3 (2×15 ml), aqueous 10% citric acid (2×15 ml), then water (2×15 ml) and dried (MgSO4). Solvent is evaporated to give an oil which is chromatographed on silica gel using ethyl acetate as eluant to yield 1-((S)-Nα -t-butoxycarbonyl-Nω -nitroarginyl)-4-(ethoxycarbonylmethyl)piperidine as a pale yellow oil, Rf (ethanol)=0.16.

Provenance & Evidence