Bromoacetonitrile → (S)-tert-butyl 5-((S)-3-((tert-butoxycarbonyl)amino)-4-(cyanomethoxy)-4-oxobutyl)thiazolidine-3-carboxylate

Participants

Reaction Steps

N,N-Diisopropylethylamine (48 μL, 0.276 mmol) and subsequently bromoacetonitrile (88 μL, 1.255 mmol) were added to a solution of (S)-2-((tert-butoxycarbonyl)amino)-4-((S)-3-(tert-butoxycarbonyl) thiazolidin-5-yl)butanoic acid (Compound tk2) (98 mg, 0.251 mmol) in acetonitrile (0.5 mL) at room temperature under a nitrogen atmosphere. The reaction mixture was stirred at the same temperature for 3 hours and then concentrated under reduced pressure, and the resulting crude product was purified by normal-phase silica gel column chromatography (hexane/ethyl acetate) to afford (S)-tert-butyl 5-((S)-3-((tert-butoxycarbonyl)amino)-4-(cyanomethoxy)-4-oxobutyl)thiazolidine-3-carboxylate (Compound tk3) (94.0 mg, 87%).

Provenance & Evidence