Hydrochloric Acid → HCID 69299427, compound

Participants

Reaction Steps

To a solution of ethyl 4-(2-carboxy-1-methylethyl)benzoate (J. I. DeGraw et al. J. Med. Chem. 1986, 29, 1056) (3.54 g, 15 mmol) in dichloromethane (100 mL) cooled in an ice bath was added oxalyl chloride (3.9 mL, 45 mmol). Dimethylformamide (0.1 mL) was added and the mixture stirred at room temperature for 2 hours, then concentrated under reduced pressure. The residual acid chloride was dissolved in dichloromethane (60 mL) and added to an ice-cooled mixture of (S)-2-phenylglycinol (2.72 g, 20 mmol) and triethylamine (6.3 mL, 45 mmol) in dichloromethane (60 mL) over 30 minutes. The reaction mixture was stirred at room temperature for 1 hour. 2N Hydrochloric acid was added, the organic phase was separated, then washed with water, dried (anhydrous magnesium sulfate) and evaporated. The diastereomeric products were separated by flash chromatography with elution by ethyl acetate, then ethyl acetate-methanol (9:1). There were obtained an earlier eluting (SS) diastereomer (P14a); TLC (silica gel; ethyl acetate) Rf 0.36; MS (ES+ve): [M+H]+ at m/z 356 (C21H25NO4 requires [M+H]+ at m/z 356); and a later eluting (RS) diastereomer (P14b); TLC (silica gel; ethyl acetate) Rf 0.19; MS (ES+ve): [M+H]+ at m/z 356 (C21H25NO4 requires [M+H]+ at m/z 356).

Provenance & Evidence