Selectfluor → Tert-butyl 3-fluoro-4-oxopiperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

Tert-butyl 4-((trimethylsilyl)oxy)-5,6-dihydropyridine-1(2H)-carboxylate, 2.2 (300 g, 1.102 mol) was dissolved in dry Acetonitrile (300 mL) and cooled to 0° C. and Selectfluor (430 g, 1.21 mol) was added in portion wise over a period of 45 min. under N2 atmosphere. After addition completed, the reaction mixture was allowed to room temperature and stirred for 2 h. The reaction was monitored by TLC (50% EtOAc/hexane). After completion of reaction by TLC the reaction mixture poured into ice cold saturated brine solution (300 mL) and extracted with EtOAc (2×200 mL). The combined EtOAc layers were washed with brine solution, water, dried over Na2SO4 and evaporated under vacuum. The residue was purified by column chromatography on silica gel (10-40% EtOAc-Hexane) to afford tert-butyl 3-fluoro-4-oxopiperidine-1-carboxylate 2.3 (170 g; 70.7%). 1HNMR (CDCl3, 400 MHz): δ 4.88 (dd, 0.5H), 4.77 (dd, 0.5H), 4.47 (brs, 1H), 4.17 (ddd, 1H), 3.25 (brs, 1H), 3.23 (ddd, 1H), 2.58 (m, 1H), 2.51 (m, 1H), 1.49 (s, 9H).

Provenance & Evidence