HCID 118307683, compound → HCID 118307738, compound

Participants

Reaction Steps

The isobutylene gas was bubbled into a nitrogen purged, cooled (0° C.) solution of (S)-isopropyl 2-(5-bromo-4-(4-fluoro-4-methylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate (600 mg, 1.44 mmol) and 0.14 mL of 70% HClO4 in DCM (15 mL) for 20 min. The reaction mixture was allowed to warm to rt and stirred for 5 days. The reaction was diluted with DCM, washed with 1M Na2CO3 solution, and dried over MgSO4. The crude product was charged (DCM) to a 80 g ISCO silica gel cartridge and gradient elution (0-25% EtOAc/hexanes) using an Isolera chromatography station gave (S)-isopropyl 2-(5-bromo-4-(4-fluoro-4-methylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate 529 mg (78%) as a mixture of diastereomers. 1H NMR (500 MHz, DMSO-d6) 6 (br. s, 1H), 4.92-4.89 (m, 1H), 4.04 (br. s, 1H), 3.51-3.48 (m, 1H), 3.37-3.36 (m, 1H), 2.85 (br. s, 1H), 2.53 (s, 3H), 2.44 (br. s, 3H), 1.95-1.67 (m, 4H), 1.42/1.36 (s, 3H), 1.17-1.14 (m, 12H), 1.0 (d, J=6.2 Hz, 3H). UPLC (M+H)=475.2.

Provenance & Evidence