Phenyl triflimide → tert-Butyl 5-(((trifluoromethyl)sulfonyl)oxy)-3,4-dihydropyridine-1(2H)-carboxylate

Participants

Reaction Steps

To a solution of lithium diisopropylamide (0.0144 mol, 2M in heptane/THF/EtPh, 7.2 mL) in tetrahydrofuran (25 mL) at −78° C. was added a solution of 3-Oxo-piperidine-1-carboxylic acid tert-butyl ester (2.00 g, 0.0100 mol) in tetrahydrofuran (5 mL) dropwise. After 15 minutes, N-phenylbis(trifluoromethanesulphonimide) (4.303 g, 0.01204 mol) in tetrahydrofuran (10 mL) was added. The reaction was slowly warmed to room temperature and stirred overnight. The reaction was cooled to 0° C. and quenched with saturated NH4Cl, diluted with water, and extracted 3 times with dichloromethane. The organic layers were combined, dried with MgSO4, and concentrated. The mixture was purified by flash chromatography (EtOAc/hexanes) to give 0.933 g of 5-Trifluoromethanesulfonyloxy-3,6-dihydro-2H-pyridine-1-carboxylic acid tert-butyl ester and 1.1234 g of 5-Trifluoromethanesulfonyloxy-3,4-dihydro-2H-pyridine-1-carboxylic acid tert-butyl ester.

Provenance & Evidence