Lithium Hexamethyldisilazide → (3s)-Tert-butyl 4-((1r)-1-(6-(5-fluoro-6-methoxypyridin-3-ylamino)-5-(2-methyl-9-(tetrahydro-2h-pyran-2-yl)-9h-purin-6-yl)pyridin-3-yl)ethyl)-3-methylpiperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of (3S)-tert-butyl 4-((1R)-1-(6-fluoro-5-(2-methyl-9-(tetrahydro-2H-pyran-2-yl)-9H-purin-6-yl)pyridin-3-yl)ethyl)-3-methylpiperazine-1-carboxylate (0.323 g, 0.599 mmol) and 5-fluoro-6-methoxypyridin-3-amine (0.170 g, 1.197 mmol) in THF (15 mL) was chilled to −20° C. in a diluted dry ice/acetone bath, then lithium bis(trimethylsilyl)amide (1.0 M in THF, Aldrich; 1.796 mL, 1.796 mmol) was added slowly via syringe into the reaction mixture. After the addition, the ice bath was removed and the mixture was allowed to stir under inert atmosphere for 1 h. The mixture was diluted with chloroform (20 mL) and water (10 mL). The organic layer was extracted with chloroform (3×10 mL). The combined organic extracts were dried over sodium sulfate, filtered and concentrated in vacuo. The crude material was adsorbed onto silica gel and purified by chromatography through a silica-gel column (80 g) eluting with 100% EtOAc to give (3S)-tert-butyl 4-((1R)-1-(6-(5-fluoro-6-methoxypyridin-3-ylamino)-5-(2-methyl-9-(tetrahydro-2H-pyran-2-yl)-9H-purin-6-yl)pyridin-3-yl)ethyl)-3-methylpiperazine-1-carboxylate (0.155 g, 0.234 mmol, 39.1% yield) as a tan solid. 1H NMR (400 MHz, CDCl3) δ 12.63 (s, 1H) 9.71 (d, J=2.15 Hz, 1H) 8.32 (dd, J=12.52, 2.15 Hz, 1H) 8.22 (s, 1H) 8.17 (d, J=2.35 Hz, 1H) 8.03 (d, J=2.15 Hz, 1H) 5.80 (dd, J=10.56, 2.15 Hz, 1H) 4.12 (s, 2H) 3.96 (s, 3H) 3.76 (d, J=2.54 Hz, 1H) 3.53 (m, 1H) 3.23 (m, 1H) 2.84 (s, 5H) 2.41 (m, 1H) 2.08 (s, 1H) 2.03 (s, 1H) 1.97 (s, 1H) 1.64 (s, 3H) 1.58 (s, 2H) 1.45 (d, J=6.85 Hz, 3H) 1.32 (s, 9H) 1.07 (d, J=5.87 Hz, 3H). m/z (ESI, +ve ion) 662.2 (M+H)+.

Provenance & Evidence