Reaktion #1106898

Reaktionsgleichung

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

vinyl boronic acid

→

title compound

Ausbeute 54.0%

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

Ausbeute 54.0%

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeA scintillation vial equipped with a stirbar
2. 2
   SonstigeThe vial was fitted with a septum-lined
3. 3
   Sonstigecap
4. 4
   Sonstigepurged with nitrogen for 5-10 min
5. 5
   workup.ADDITIONTo this mixture was added dioxane (16.6 volume equivalents)
6. 6
   Sonstigedegassed 2N K2CO3 (4.2 volume equivalents) by syringe
7. 7
   TemperaturThe mixture was cooled to room temperature
8. 8
   workup.ADDITIONdiluted with 12 volume equivalents EtOAc
9. 9
   Waschenwashed with twice with saturated aq. NaHCO3
10. 10
    TrocknenThe organic layer was dried over sodium sulfate
11. 11
    Filtrationfiltered
12. 12
    Einengenconcentrated in vacuo

Vorschrift

A scintillation vial equipped with a stirbar was charged with (S)-6-bromo-1-(1-phenylethyl)-1H-imidazo[4,5-b]pyrazin-2-ol (1.0 equiv), vinyl boronic acid (2.2 equiv), and (DPPF)PdCl2 (0.10 equiv). The vial was fitted with a septum-lined cap and purged with nitrogen for 5-10 min. To this mixture was added dioxane (16.6 volume equivalents) and degassed 2N K2CO3 (4.2 volume equivalents) by syringe. The resulting mixture was heated to 90° C. overnight. The mixture was cooled to room temperature, diluted with 12 volume equivalents EtOAc, washed with twice with saturated aq. NaHCO3, and once with brine. The organic layer was dried over sodium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Biotage MPLC 5%-40% EtOAc/Hexanes) provided the title compound as an off-white solid (54%). LCMS m/z (APCI)=267.0 (M+H).

Quelle