Di-tert-butyl azodicarboxylate → HCID 11016430, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of diisopropylamine (0.77 mL, 5.53 mmol) in THF (4 mL) at 0° C. is added BuLi (2.17 mL, 5.42 mmol, 2.5 M in hexane) dropwise. The solution is stirred at 0° C. for 30 minutes to form an LDA solution. The LDA solution is cold to −70° C. and added to a solution of (S)-4-benzyl-3-(4-bromo-butyryl)-oxazolidin-2-one (1.72 g, 5.07 mmol) in THF (4 mL) at −70° C. dropwise. After stirring at −70° C. for 2 hours, a solution of di-t-butyl azodicarboxylate (1.40 g, 6.08 mmol) in CH2Cl2 (4 mL) is added slowly. After stirring at −70° C. for 15 minutes, Bu4NI (0.28 g, 0.76 mmol) is added in one portion. After stirring at −70° C. for 10 minutes, the flask with reaction mixture is moved to a −20° C. bath and stirred overnight (16 hours). The reaction mixture is quenched to ether (50 mL) with buffer solution (50 mL, Ph=7), and the mixture is extracted with ether (3×50 mL). The organic layer is dried over Na2SO4 and concentrated. The crude product is purified by chromatography (hexane/EtOAc:70/30) to give (S)-3-((S)-4-benzyl-2-oxo-oxazolidine-3-carbonyl)-tetrahydro-pyridazine-1,2-dicarboxylic acid di-tert-butyl ester as white solid (1.22 g, 49.3%). (NMR and MS data confirmed, U-3133-55-30).

Provenance & Evidence