Potassium Carbonate → tert-butyl 3-(6-aminopyridin-3-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate

Temperatur

70 °C

In a 250 mL round-bottomed flask, 3-trifluoromethanesulfonyloxy-2,5-dihydro-pyrrole-1-carboxylic acid tert-butyl ester (2.3 g, 7.25 mmol, Eq: 1.00) was combined with THF (60 ml) to give a colorless solution. The solution was purged with argon for 10 min. Potassium carbonate (5.06 g, 36.2 mmol, Eq: 5.0), 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2-amine (1.91 g, 8.7 mmol, Eq: 1.20), tetrakis(triphenylphosphine)palladium(0) (83.8 mg, 72.5 μmol, Eq: 0.01) and water (1.2 ml) were added. The reaction mixture was heated to 70° C. and stirred for 16 h. The reaction mixture was poured into saturated NaHCO3 and extracted twice with Et2O. The organic layer was washed with brine, dried over Na2SO4 and concentrated in vacuo. The crude material was purified by flash chromatography (silica gel, 60 g, 50% (60:10:1 DCM:MeOH:NH4OH)/DCM) to give tert-butyl 3-(6-aminopyridin-3-yl)-2,5-dihydro-1H-pyrrole-1-carboxylate (1.03 g, 54%). LC/MS-ESI observed [M+H]+ 262.

1. customto give a colorless solution
2. customThe solution was purged with argon for 10 min
3. extractionextracted twice with Et2O
4. washThe organic layer was washed with brine
5. dry with materialdried over Na2SO4
6. concentrationconcentrated in vacuo
7. customThe crude material was purified by flash chromatography (silica gel, 60 g, 50% (60:10:1 DCM:MeOH:NH4OH)/DCM)

ORD-Eintrag

ord-ce56d8dfa05b478da79a6fc2b1135d5c

Quelldatensatz

uspto-grants-2013_07

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08481540B2