Benzyl chloroformate → HCID 68293158, compound

Participants

Reaction Conditions

Reaction Steps

(S)-Methyl 3-amino-3-(4-fluorophenyl)propionate hydrochloride (4.5 g) was dissolved in THF (30 ml) and cooled to 0° C. After the addition of diisopropylethylamine (8.8 g), benzyl chloroformate (4.3 g) was slowly added dropwise and the mixture was stirred at 0° C. for 1 hour. The reaction mixture was concentrated by rotary evaporation, dichloromethane (50 ml) was added and the mixture was washed twice with NH4Cl solution. Subsequently, the organic phase was dried with MgSO4, filtered and concentrated. The residue (5.72 g) was taken up in THF, titanium tetraisopropoxide (0.49 g) was added, and ethylmagnesium bromide (3 N, 17.9 ml) was added dropwise over the course of 1 hour. After 24 hours, the reaction solution was poured into cold 2 N sulfuric acid (150 ml) and extracted three times with dichloromethane. The combined organic phases were dried with MgSO4, filtered and concentrated. The residue was purified by preparative HPLC. The resulting (S)-1-(4-fluorophenyl)-2-(1-hydroxycyclopropyl)ethyl]carbamic acid benzyl ester (0.76 g) was dissolved in methanol (20 ml), 5% Pd/C was added and hydrogenation was effected under hydrogen pressure 2 bar. After filtration and concentration, the product (87 mg) was thus obtained with a molecular weight of 329.3 g/mol (C19H20FNO3), MS (ESI): m/e=330 (M+H+).

Provenance & Evidence