反应详情

A mixture of (2S)-ethyl 2-(2-amino-7-(8-fluoro-5-methylchroman-6-yl)-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)-2-(tert-butoxy)acetate (1.20 g, 2.55 mmol), 1N NaOH (3.83 mL, 3.83 mmol) in EtOH (20 mL) was stirred at rt for 16 h. LCMS indicated a small amount of starting material remaining, therefore, the reaction mixture washeated at 60° C. for 2 h. At this time, LCMS indicated that the ester hydrolysis was complete. The reaction mixture was then concentrated in vacuo, and the residue was adjusted to pH=4 using 1N HCl. A white precipitate formed and was collected by filtration, washed with water, and dried in vacuo to obtain (2S)-2-(2-amino-7-(8-fluoro-5-methylchroman-6-yl)-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)-2-(tert-butoxy)acetic acid (1.06 g, 2.16 mmol, 85% yield) as a off-white solid. 1H NMR (500 MHz, CDCl3) δ 6.90 (d, J=10.56 Hz, 1H), 5.91 (s, 1H), 4.97 (s, 1H), 4.26-4.35 (m, 2H), 2.74 (m, 2H), 2.65 (s, 3H), 2.11-2.18 (m, 2H), 1.95 (s, 3H), 1.21 (s, 9H). LCMS (M+H)=443.23.

1. waitthe reaction mixture washeated at 60° C. for 2 h
2. concentrationThe reaction mixture was then concentrated in vacuo
3. customA white precipitate formed
4. filtrationwas collected by filtration
5. washwashed with water
6. customdried in vacuo