Water → 2-(4-Fluorophenyl)-8-vinylimidazo[1,2-a]pyrazine

Temperature

95 °C

To a mixture of 8-chloro-2-(4-fluorophenyl)-imidazo[1,2-a]pyrazine (Example #6, Step A, 3.96 g, 16 mmol) in dioxane (80 mL) was added water (15.4 mL), sodium carbonate (EM Science, 5.08 g, 48 mmol), tri-t-butylphosphine tetrafluoroborate (Strem, 0.46 g, 1.6 mmol), and tris(dibenzylideneacetone)dipalladium(0) (0.73 g, 0.8 mmol). The reaction was degassed with nitrogen and then vinylboronic acid pinacolester (5.44 mL, 32 mmol) was added. The mixture was heated to about 95° C. for about 16 h. The reaction was cooled, EtOAc was added (250 mL), and the mixture was washed with water. The organic layer was dried over sodium sulfate, filtered, and evaporated. The residue was purified by FCC (33%-50% EtOAc/heptane). The residue was triturated with heptane and filtered to yield the title compound as a brown solid (2.46 g, 62%): LC/MS (Table 1, Method b) Rt=2.74 min; MS m/z: 240.3 (M+H)+.

1. customThe reaction was degassed with nitrogen
2. additionvinylboronic acid pinacolester (5.44 mL, 32 mmol) was added
3. temperatureThe reaction was cooled
4. additionEtOAc was added (250 mL)
5. washthe mixture was washed with water
6. dry with materialThe organic layer was dried over sodium sulfate
7. filtrationfiltered
8. customevaporated
9. customThe residue was purified by FCC (33%-50% EtOAc/heptane)
10. customThe residue was triturated with heptane
11. filtrationfiltered

ORD record

ord-c81084fa5c8e49cd97f9962520398057

Source dataset

uspto-grants-2010_05

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07709468B2