Iodoethane → (s)-Allyl-(8,8-diethyl-4-oxo-6-phenylcarbamoyl-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidin-3-yl)-carbamic acid benzyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a solution of phenyl amide 18b (100 mg, 0.225 mmol) in 1 mL THF at −78° C., was added LiHMDS (IM in THF, 0.720 mL, 0.720 mmol). The orange solution was stirred at −78° C. for 5 min, then EtI (0.045 mL, 0.563 mmol) was added. The reaction was stirred and allowed to slowly warm to −30° C. over 45 min. Additional LiHMDS (IM in THF, 0.250 mL, 0.250 mmol) and EtI (0.025 mL) were added and the mixture was allowed to warm to −20° C. over 30 min. The reaction was quenched with the addition of sat. NH4Cl. The mixture was diluted with EtOAc. The organic phase was washed with H2O and brine, dried (Na2SO4) and concentrated. The crude product was purified by flash chromatography (40 to 45% EtOAc/hexanes) to afford 81.1 mg (72%) of 37a as a colorless foam. MS (ESI) 501.3 (M+H+), 523.3 (M+Na+), 499.4 (M−H+), 535.3 (M+Cl−).

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