Allyl chloroformate → HCID 6709788, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of L-Tyrosine methyl ester hydrochloride (25 g, 107.9 mmol, 1.0 equiv) in THF (500 mL) and CH2Cl2 (250 mL) at room temperature was added diisopropyl ethylamine (56.5 ml, 322.5 mmol, 3.0 equiv). The solution was cooled to 0° C. and allylchoroformate (11.5 ml, 107.9 mmol, 1.0 equiv) was added dropwise. The reaction was stirred at 0° C. for 1.5 hours, after which time saturated ammonium chloride (100 mL) was added and the THF and CH2Cl2 were removed under reduced pressure. The aqueous suspension was extracted with ether (4×300 mL). The organics were combined, washed with brine, dried over MgSO4, and concentrated. Purification by flash chromatography (15→60% EtOAc/hexane) afforded 18 (30 g, 96%) as a white solid. Rf=0.43 (50% EtOAc/hexane); FTIR (neat, cm−1) 3297, 2959, 1734, 1688, 1566, 1518, 1441, 1229; 1H NMR (400 MHz, CDCl3) δ6.95 (d, J=7.9 Hz, 2H), 6.71 (d, J=8.0 Hz, 2H), 5.85 (m, 1H), 5.24 (m, 3H), 4.6 (m, 1H), 4.53 (d, J=5.2, 2H), 3.71 (s, 3H), 3.01 (m, 2H); 13C NMR (100 MHz, CDCl3) δ172.3, 155.8, 155.2, 132.3, 130.3, 127.0, 118.0, 115.5, 66.0, 54.9, 52.9, 52.4, 37.4; HRMS (ES+) calculated for C14H17NO5 (M+H)+: 280.1107, found: 280.1195.

Provenance & Evidence