Diisopropylamine → HCID 59657499, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 15 mL (124 mmol) diisopropyl amine in 90 mL anhydrous THF at −40° C. was added dropwise 45 mL (113 mmol) of n-butyl lithium (2.5 M in hexanes) The reaction mixture was warmed to 0° C. A solution of 6.7 mL (62.1 mmol) hexanoic acid acid in 60 mL anhydrous THF was added dropwise. The reaction mixture stirred at −20° C. for an additional 20 m. The reaction mixture was cooled to −78° C. A solution of 15 g (64.3 mmol) benzyl 4-oxo-1-piperidine-carboxylate in 60 mL anhydrous THF was added dropwise. The reaction mixture slowly warmed to room temperature over 18 h. The reaction was quenched by addition of 25 mL of water. The mixture was acidified to pH 2 with 6N HCl. The aqueous layer was thrice extracted with EtOAc. The combined organic phase was dried over magnesium sulfate and evaporated under reduced pressure. Toluene was added to the light, yellow oil and evaporated under reduced pressure to provide 21.5 g (99%) of 4-(1-carboxy-pentyl)-4-hydroxy-piperidine-1-carboxylic acid benzyl ester: ms [M]+=350.

Provenance & Evidence