Water → 6-(5-chloro-2-fluoropyridin-3-yl)-2-methyl-9-(tetrahydro-2H-pyran-2-yl)-9H-purine

Participants

Reaction Conditions

Reaction Steps

6-Chloro-2-methyl-9-(tetrahydro-2H-pyran-2-yl)-9H-purine (0.500 g, 1.979 mmol) and 5-chloro-2-fluoropyridin-3-ylboronic acid (1.388 g, 7.91 mmol) (Combi-Blocks, Inc., San Diego, Calif.) in THF (25 ml) were added to a 100 mL round-bottomed flask. Potassium acetate (0.583 g, 5.94 mmol) was added to the mixture, followed by water (1 mL). The mixture was evacuated, then backfilled with Nitrogen gas. Then bis(di-tert-butyl(4-dimethylaminophenyl)phosphine)dichloropalladium(II) (0.050 g) (Aldrich, St. Louis, Mo.) was added into the mixture. The mixture was evacuated, then backfilled with nitrogen gas. The flask was fitted with a reflux condenser, then placed into a pre-heated (90° C.) oil bath and allowed to stir under inert atmosphere for 2 h. The progress of the reaction was monitored by LCMS, which showed mostly desired product. The reaction mixture was allowed to cool to room temperature, diluted with water (10 mL) and extracted with CH2Cl2 (3×25 mL). The organic extracts were washed with satd aqueous Na2CO3 (1×20 mL) and dried over Na2SO4. The solution was filtered and concentrated in vacuo to give the crude material as a tan oil. The crude material was adsorbed onto a plug of silica gel and purified by chromatography through a Redi-Sep RediSep®, Teledyne ISCO, Lincoln, Nebr., pre-packed silica gel column (120 g), eluting with a gradient of 1% to 40% EtOAc in CH2Cl2, to give 6-(5-chloro-2-fluoropyridin-3-yl)-2-methyl-9-(tetrahydro-2H-pyran-2-yl)-9H-purine (0.502 g, 1.443 mmol, 73.0% yield) as yellow solid. 1H NMR (400 MHz, CDCl3) δ 8.37-8.45 (m, 1H); 8.27-8.33 (m, 2H); 5.79-5.92 (m, 1H); 4.14-4.26 (m, 1H); 3.74-3.91 (m, 1H); 2.89 (s, 3H); 1.96-2.25 (m, 3H); 1.63-1.91 (m, 3H). m/z (ESI, +ve) 348 (M+H)+.

Provenance & Evidence