Hydrochloric Acid → HCID 59432811, compound

Participants

Reaction Steps

A solution of ethyl 2-amino-4-methyl-4-pentenoate (2.84 g, 18.1 mmol, prepared as in Reaction Scheme 19 from (benzhydrylideneamino)acetic acid ethyl ester and 1-bromo-2-methyl-2-propene) in CH2Cl2 (250 mL) was reacted with 4-chlorobenzenesulfonyl chloride (4.20 g, 19.9 mmol) and Et3N (3.78 mL, 27.2 mmol). After 4 h, the resulting mixture was poured into 1 N aqueous HCl (500 mL) and extracted with EtOAc (3×150 mL). The organic layer was washed with brine (50 mL), dried (MgSO4), filtered, and concentrated in vacuo. The crude concentrate was purified using silica gel column chromatography (10:1 to 5:1 gradient, hexanes/EtOAc) to afford 3.04 g (25% yield over 3 steps) of ethyl 2-(4-chlorobenzenesulfonylamino)-4-methyl-4-pentenoate: LCMS (M+Na)+354.2; 1H NMR (400 MHz, CDCl3) 7.77 (d, 2H, J=9.1), 7.46 (d, 2H, J=8.8), 5.07 (d, 1H, J=9.0), 4.84 (s, 1H), 4.73 (s, 1H), 4.05 (m, 1H), 3.95 (q, 2H, J 7.1), 2.40 (m, 2H), 1.66 (s, 3H), 1.13 (t, 3H, J=7.1).

Provenance & Evidence