Ammonium Chloride → (2S)-2-Isopropyl-2-hydroxy-3-(2-fluorophenyl)propanoic acid

Participants

Reaction Conditions

Reaction Steps

A solution of (o-fluorobenzyl)magnesium bromide in diethyl ether (100 mL), prepared from the corresponding o-fluorobenzyl bromide (9.45 g, 50.0 mmol) and magnesium turnings (1.32 g, 55.0 mmol), was added to a solution of ethyl 3-methyl-2-oxobutanoate (7.2 g, 50 mmol) in diethyl ether (50 mL) cooled at −78° C. After 30 min at −78° C., the reaction mixture was warmed to 0° C. and poured into saturated aqueous NH4Cl. The organic layer was washed with brine, dried and concentrated. The residue was dissolved in methanol (200 mL) and kept with 2 N KOH (75 mL) for 2 hrs. at 50° C. The reaction mixture was diluted with water and washed with hexane. The aqueous layer was acidified with 2 N HCl, saturated with sodium chloride and extracted with ethyl acetate. Removal of solvents gave the title compound.

Provenance & Evidence