Ethyl orthoformate → HCID 10964674, compound

Participants

Reaction Conditions

Reaction Steps

To a suspension of D-cysteine 1.5 hydrate hydrochloride (Q-1, Scheme Q where RQ-1 and RQ-1 are equal to hydrogen, RQ-3 is hydrogen and stereochemistry is (S)) (5 g, 27.1 mmol) in absolute ethyl alcohol (50 mL) was added triethylorthoformate (13.5 mL, 81.2 mmol) at ambient temperature. A stream of anhydrous HCl gas was bubbled through the solution for 30 min. The stream of anhydrous HCl gas was maintained as the mixture heated to 70° C. for 2 h. The reaction mixture was concentrated in vacuo and the resulting residue triturated with diethyl ether to afford D-cysteine ethyl ester (4.43 g) as a white solid which was used without further purification. Physical data as follows: 1H NMR (300 MHz, D2O) 4.36 (1H), 4.27 (2H), 3.12 (2H), 1.25 (3H); MS (ESI+) for C5H11NO2S m/z 150.0 (M+H)+.

Provenance & Evidence