tert-Butyl bromoacetate → (6R,8S)-[3-(allyl-benzyloxycarbonyl-amino)-8-methyl-4-oxo-6-phenylcarbamoyl-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidin-8-yl]-acetic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To Intermediate 18c (495.7 mg, 1.08 mmol) in THF at −78° C. was added LiHMDS (2.268 mL, 2.268 mmol) dropwise. After 10 min, tert-butyl bromoacetate was added and the mixture was stirred at −78° C. for 20 min. It was allowed to warm to −40° C. over 20 min, then quenched with NH4Cl. The reaction mixture was diluted with EtOAc, then washed with H2O, brine, dried (Na2SO4) and concentrated. It was purified by SiO2 chromatography (50% EtOAc/hexanes) to afford 367.9 mg (59%) of intermediate 38a.

Herkunft & Nachweise