Ethanethiol → HCID 86592555, compound

Participants

Reaction Steps

To a solution containing (R)-2-benzyloxycarbonylamino-3-methyl-butyric acid (5.0 g, 20.0 mmol) in anhydrous CH2Cl2 (20 mL) is added DMAP (258 mg, 2.0 mmol) followed by chilled EtSH (1.6 mL, 22.0 mmol). Dicyclohexylcarbodiimide (4.5 g, 22.0 mmol) is added in one portion and the reaction is complete after 30 min. The solid material is removed by vacuum filtration and the filtrate is concentrated. The crude product is purified by flash silica gel chromatography (hexane to 8:1 hexane/EtOAc) to provide (R)-2-benzyloxycarbonylamino-3-methyl-thiobutyric acid S-ethyl ester (5.21 g, 88%) as a colorless oil. 1H NMR (300 MHz, CDCl3) δ0.85 (d, J=6.8 Hz, 3H), 0.98 (d, J=6.8 Hz, 3H), 1.23 (t, J=7.5 Hz, 3H), 2.27 (m, 1H), 2.88 (q, J=7.5 Hz, 2H), 4.35 (dd, J=9.5, 4.6 Hz, 1H), 5.13 (s, 2H), 5.25 (br d, J=9.5 Hz, 1H), 7.30-7.36 (m, 5H) ppm.

Provenance & Evidence