Diisopropylamine → Tert-butyl 4-(trifluoromethanesulfonyloxy)-1,2,3,6-tetrahydropyridine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirring solution of diisopropylamine (38.7 mL, 276 mmol) in THF (900 mL) at 0° C. was added dropwise via an addition funnel a solution of n-BuLi in hexanes (1.6 M, 171.5 mL, 276 mmol). After 25 min, the solution was cooled to −78° C. To this solution was added dropwise via an addition funnel a solution of 1-Boc-4-piperidinone (50 g, 250.9 mmol) in THF (300 mL). After 30 min, a solution of N-phenyltrifluoromethanesulfonamide (95.9 g, 268.5 mmol) in THF (300 mL) was added and the solution was warmed to 0° C. After 3 h, the solvents were evaporated in vacuo and the residue was loaded onto a silica gel column with a minimal amount of dichloromethane and eluted with 5% ethyl acetate/hexanes. The product containing fractions were combined and concentrated in vacuo to give 74.84 g (90%) of a light yellow oil.

Provenance & Evidence