4-Fluorobenzaldehyde → HCID 71060378, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 1M LHMDS (8.55 mL, 8.55 mmol) in THF was cooled to −78° C. and to this mixture 4-fluorobenzaldehyde (839 ul, 7.77 mmol) in THF (25 mL) was added dropwise. The mixture was left to stir for 50 minutes and allowed to warm to 0° C. for 10 minutes and cooled again to −78° C. In a different flask a solution of 1M LHMDS (8.55 mL, 8.55 mmol) was cooled to −78° C. and a solution of piperidine-1,3-dicarboxylic acid 1-tert-butyl ester 3-ethyl ester (2 g, 7.77 mmol) in THF (25 mL) was added dropwise. The mixture was left to stir for 40 minutes and allowed to warm to 0° C. for 10 minutes and cooled again to −78° C. The solution of trimethylsilylenamine was added dropwise to the solution of enolate maintaining the temperature below 0° C. After the addition was complete, the reaction was left to stir for 3 hours at 0° C. and allowed to warm to room temperature overnight. The reaction was quenched with water (5 ml) and the resulting solution was extracted using ethyl acetate. The organic portion was separated, dried (MgSO4) and concentrated in vacuo to yield a yellow oil. Purification by flash chromatography on silica (80 g column) eluting with 0-100% EtOAc in iso-hexane afforded the title compound;

Provenance & Evidence