C(N1C=CN=C1)(N1C=CN=C1)=O.[C:13]([O:17][C:18]([N:20]1[CH2:24][CH2:23][C@H:22]([C:25]([OH:27])=O)[CH2:21]1)=[O:19])([CH3:16])([CH3:15])[CH3:14].Cl.[CH3:29][NH:30][O:31][CH3:32]>ClCCl>[C:13]([O:17][C:18]([N:20]1[CH2:24][CH2:23][C@H:22]([C:25](=[O:27])[N:30]([O:31][CH3:32])[CH3:29])[CH2:21]1)=[O:19])([CH3:14])([CH3:15])[CH3:16]Add 1,1′-carbonyldiimidazole (414.33 g, 2.56 mol) portion wise to a stirred solution of (S)-N-tert-butoxycarbonylpyrrolidine-3-carboxylic acid (500 g, 2.32 mol) in dichloromethane (5.81 L) and stir at room temperature under nitrogen for 1 hour. Add N,O-di-methylhydroxylamine hydrochloride (253.04 g, 2.56 mol) and stir at room temperature for 48 hours. Quench the reaction with 1N HCl, and extract with ethyl acetate (2×). Wash the combined organics with saturated NaHCO3 and brine. Dry (MgSO4), filter and concentrate under reduced pressure to provide 535 g (89%) of the title compound. MS (m/z)=203 (M−55).
Wird geladen…
