反应详情

To a solution of N-(5-Bromo-3-trimethylsilanylethynyl-pyrazin-2-yl)-acetamide (474 mg, 1.52 mmol) in THF (4 ml) was added dropwise a 1 M solution of tetra-n-butyl ammonium fluoride in THF (3.3 ml, 3.3 mmol). After stirring at reflux for 15 hours, the reaction mixture was concentrated in vacuum and water added. The aqueous layer was extracted three times with dichloromethane and the combined extracts were directly adsorbed on silica gel. Purification by silica gel chromatography with a gradient of ethyl acetate/hexanes afforded the title compound (130 mg, 43% yield) as a yellow solid. 1H-NMR (500 MHz, d6-DMSO) δ12.38 (s br, 1H), 8.38 (s, 1H), 7.95 (d, 3.5 Hz, 1H), 6.61 (d, 3.5 Hz, 1H). MS: m/z 197.9/199.9 [MH+].

1. temperatureat reflux for 15 hours
2. concentrationthe reaction mixture was concentrated in vacuum and water
3. additionadded
4. extractionThe aqueous layer was extracted three times with dichloromethane
5. customPurification by silica gel chromatography with a gradient of ethyl acetate/hexanes