Hydrochloric Acid → 2-(4-fluoro-phenyl)-4-oxo-5-triisopropylsilanyl-3,4-dihydro-2H-pyridine-1-carboxylic acid 5-methyl-2-(1-methyl-1-phenyl-ethyl)-cyclohexyl ester

Participants

Reaction Conditions

Reaction Steps

Following the procedure reported in JACS 1994, 116, 4719-4728, to a solution of 4-methoxy-3-triisopropylsilanyl-pyridine (6.06 g, 22.8 mmol) in toluene (160 mL) at −25° C. was added a solution of 5-methyl-2-(1-methyl-1-phenyl-ethyl)-cyclohexyl chloroformate (6.73 g, 26.2 mmol) in toluene (140 mL). After 15 minutes the mixture was cooled to −78° C. and 1.0M 4-fluorophenyl magnesium bromide in THF (26.1 mL, 26.2 mmol) was added slowly. The mixture was stirred at −78° C. for 1 hour. 2N HCl was added and the mixture was allowed to warm to room temperature and was stirred for additional 15 minutes. The mixture was extracted with ethyl acetate, washed with water and brine, dried over MgSO4, filtered and concentrated to dryness. Purification of the residue by flash chromatography (hexane/ethyl acetate 9:1) gave 2-(4-fluoro-phenyl)-4-oxo-5-triisopropylsilanyl-3,4-dihydro-2H-pyridine-1-carboxylic acid 5-methyl-2-(1-methyl-1-phenyl-ethyl)-cyclohexyl ester (1.06 g, 48%) as a white solid.

Provenance & Evidence