Triethylamine → (S)-2-(tert-butoxycarbonylamino)-4-(methylthio)butyl methanesulfonate

Participants

Reaction Conditions

Reaction Steps

To a solution of (S)-tert-butyl 1-hydroxy-4-(methylthio)butan-2-ylcarbamate (1.0 g, 1.0 eq, Chem-Impex, Catalog #03206) in DCM at −25° C. was added triethylamine (2.5 eq), followed by methanesulfonyl chloride (2.0 eq). The mixture was stirred at −25° C. for 1 h and RT for 30 min, washed with 1 N HCl, sat. NaHCO3 and brine, dried and concentrated to give a residue, which was purified by flash chromatography column on silica gel using ethyl acetate and hexane (1:2) as eluent to give (S)-2-(tert-butoxycarbonylamino)-4-(methylthio)butyl methanesulfonate (1.1 g, 75%). 1H NMR (CDCl3, 300 MHz) d 4.25 (m, 2H, OCH2), 4.0 (br s, 1H, BocNHCH), 3.05 (s, 3H, SO2CH3), 2.55 (m, 2H, SCH2), 2.15 (s, 3H, SCH3), 1.85 (m, 2H, BocNHCHCH2CH2S), 1.45 (s, 9H, OC(CH3)3).

Provenance & Evidence