反应详情

温度

100 °C

A mixture of 3-bromo-2-fluoro-5-methylpyridine (202 mg, 1.06 mmol), 4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi-1,3,2-dioxaborolane (300 mg, 1.17 mmol), potassium acetate (208 mg, 2.12 mmol) and PdCl2(PPh3)2 (37 mg, 0.053 mmol) in dioxane (4 mL) was stirred for 3 hours at 100° C. To the mixture was added di-tert-butyl (6′-bromotrispiro[cyclobutane-1,2′-chromene-4′,4″-[1,3]oxazole-3′,3′″-oxetan]-2″-yl)imidodicarbonate (300 mg, 0.531 mmol), sodium carbonate (225 mg, 2.12 mmol) and H2O (1 mL), and the mixture was stirred for 1.5 hours at 100° C. The mixture was treated with charcoal, and filtered off. The filtrate was partitioned between EtOAc and water. The organic layer was washed with brine, dried over MgSO4, filtered, and the filtrate was evaporated to give a pale brown oil. The oil was dissolved in toluene (5 mL) and to the mixture was added silicagel (neutral; 600 mg). The mixture was refluxed for 1 hour. The solvent was evaporated off. Silicagel column chromatography (CHCl3-EtOH, linear gradient of EtOH from 0 to 20%) afforded a solid. The solid was triturated in Et2O and collected by filtration, washed with Et2O and dried in vacuo at 70° C. to give 6′-(2-fluoro-5-methylpyridin-3-yl)trispiro[cyclobutane-1,2′-chromene-4′,4″-[1,3]oxazole-3′,3′″-oxetan]-2″-amine (130 mg).

1. stirringthe mixture was stirred for 1.5 hours at 100° C
2. filtrationfiltered off
3. customThe filtrate was partitioned between EtOAc and water
4. washThe organic layer was washed with brine
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. customthe filtrate was evaporated
8. customto give a pale brown oil
9. additionwas added silicagel (neutral; 600 mg)
10. temperatureThe mixture was refluxed for 1 hour
11. customThe solvent was evaporated off
12. customSilicagel column chromatography (CHCl3-EtOH, linear gradient of EtOH from 0 to 20%) afforded a solid
13. customThe solid was triturated in Et2O
14. filtrationcollected by filtration
15. washwashed with Et2O
16. customdried in vacuo at 70° C.