Benzyl chloroformate → (2S)-4-[[3-carboxy-3-(phenylmethoxycarbonylamino)propyl]disulfanyl]-2-(phenylmethoxycarbonylamino)butanoic acid

Participants

Reaction Conditions

Reaction Steps

L-Homocystine (200.0 g, 745.5 mmol, 1.0 eq.) is suspended in THF (1000 mL, 5.0 vol.) and cooled to 5-10° C. Addition of 20% sodium hydroxide (521.7 mL, 626.2 g, 125.25 g at 100%, 3.13 mmol, 4.2 eq.) is followed by addition of benzyl chloroformate (220.3 mL, 267 g, 1565.5 mmol, 2.1 eq.). Conversion is complete after a night at room temperature (L-Homocystine<1%). Extractions and washings of the organic layer with water leads to a yellow oil which is isolated in quantitative yield, and which slowly crystallizes as a yellowish solid at room temperature.

Provenance & Evidence