Reaktion #1904215

Reaktionsgleichung

CDI

(S)-6-bromo-N2-(1-phenylethyl)pyrazine-2,3-diamine

carbonyldiimidazole

→

title compound

Ausbeute 66.0%

(S)-6-bromo-1-(1-phenylethyl)-1H-imidazo[4,5-b]pyrazin-2-ol

Ausbeute 66.0%

Lösungsmittel

THF

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigewas consumed (approx. 3.6 equiv total)
2. 2
   SonstigeAfter complete reaction
3. 3
   Sonstigequenched by the careful addition of water until gas evolution
4. 4
   workup.ADDITIONThe mixture was diluted with 25 volume equivalents of EtOAc
5. 5
   Waschenwashed with 3×7.5 volume equivalents of water and 1×7.5 volume equivalents of brine
6. 6
   TrocknenThe organic layer was dried over anhydrous sodium sulfate
7. 7
   Filtrationfiltered
8. 8
   Einengenconcentrated in vacuo

Vorschrift

To a solution of (S)-6-bromo-N2-(1-phenylethyl)pyrazine-2,3-diamine (1.0 equiv) in refluxing anhydrous THF (5 volume equivalents) was added carbonyldiimidazole (CDI). Successive portions of CDI were added until the starting material was consumed (approx. 3.6 equiv total) as judged by TLC (50% EtOAc/Hexanes). After complete reaction, the mixture was cooled to room temperature and quenched by the careful addition of water until gas evolution had ceased. The mixture was diluted with 25 volume equivalents of EtOAc and washed with 3×7.5 volume equivalents of water and 1×7.5 volume equivalents of brine. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated in vacuo. Flash chromatography (Biotage MPLC 5%-40% EtOAc/Hexanes) provided the title compound (66%) as a white solid. LCMS m/z (APCI)=319.0, 321.0 (M+H).

Quelle