Reaktion #11065

Reaktionsgleichung

trisyl azide

AcOH

( 18c )

(6S,8RS)-allyl-(8-methyl-4-oxo-6-phenylcarbamoyl-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidin-3-yl)-carbamic acid benzyl ester

LiHMDS

→

azide

Ausbeute 65.0%

(6S,8R)-allyl-(8-azido-8-methyl-4-oxo-6-phenylcarbamoyl-4,6,7,8-tetrahydro-pyrrolo[1,2-a]pyrimidin-3-yl)-carbamic acid benzyl ester

Ausbeute 65.0%

Lösungsmittel

EtOAc

THF

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGThe reaction was stirred at −78° C. for 1.5 h
2. 2
   workup.STIRRINGThe mixture was stirred at rt for 1 h
3. 3
   WaschenThe organic phase was washed with 1N HCl, H2O and brine
4. 4
   Trocknendried (Na2SO4)
5. 5
   Einengenconcentrated
6. 6
   SonstigeThe product was purified by flash chromatography (35 to 40% EtOAc/hexanes)

Vorschrift

To a solution of the methyl diastereomers (18c) (3.90 g, 8.51 mmol) in 40 mL THF at −78° C., was added LiHMDS (IM in THF, 17.9 mL, 17.9 mmol). The red solution was stirred at −78° C. for 5 min, then a solution of trisyl azide (2.90 g, 9.36 mmol) in 8 mL THF was added. The reaction was stirred at −78° C. for 1.5 h, then was quenched with the addition of AcOH (2.19 mL, 38.3 mmol). The mixture was stirred at rt for 1 h, then was diluted with EtOAc. The organic phase was washed with 1N HCl, H2O and brine, dried (Na2SO4), and concentrated. The product was purified by flash chromatography (35 to 40% EtOAc/hexanes) to afford 2.764 g (65%) of azide 18d. MS (ESI) 500.4 (M+H+), 522.4 (M+Na+).

Quelle