Triacetoxyperiodinane → (S)-ethyl 2-(tert-butoxy)-2-(7-(4-(((R)-5-((tert-butyldiphenylsilyl)oxy)hexyl)oxy)-4-methylpiperidin-1-yl)-2-formyl-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)acetate

Participants

Reaction Steps

To a solution of (S)-ethyl 2-(tert-butoxy)-2-(7-(4-(((R)-5-((tert-butyldiphenylsilyl)oxy)hexyl)oxy)-4-methylpiperidin-1-yl)-2-(hydroxymethyl)-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)acetate (2 g, 2.59 mmol) in CH2Cl2 (30 mL) was added Dess-Martin periodinane (1.317 g, 3.10 mmol) and the resulting mixture was stirred at room temp for 3 h. Sat. NaHCO3 solution was then added and the mixture was extracted with dichloromethane (50 mL), dried (Na2SO4), filtered and concentrated. The residue was then purified by Biotage (5-30% EtOAc/hexane) to afford (S)-ethyl 2-(tert-butoxy)-2-(7-(4-(((R)-5-((tert-butyldiphenylsilyl)oxy)hexyl)oxy)-4-methylpiperidin-1-yl)-2-formyl-5-methylpyrazolo[1,5-a]pyrimidin-6-yl)acetate (1.9 g, 2.464 mmol, 95% yield) as viscous oil. 1H NMR (500 MHz, CDCl3) δ 10.15 (d, J=5.4 Hz, 1H), 7.74-7.66 (m, 4H), 7.47-7.34 (m, 6H), 7.02 (s, 1H), 5.88 (br. s., 1H), 4.30-4.18 (m, 2H), 3.94-3.81 (m, 1H), 3.40-3.28 (m, 3H), 2.64 (s, 3H), 2.02-1.85 (m, 3H), 1.68 (br. s., 1H), 1.57-1.52 (m, 2H), 1.50-1.39 (m, 3H), 1.31 (s, 3H), 1.28-1.25 (m, 3H), 1.25 (s, 9H), 1.09 (d, J=6.1 Hz, 3H), 1.07 (s, 9H). 4 missing piperidine hydrogens. LCMS (M+H)=772.3.

Provenance & Evidence