Trifluoroacetic acid → L-alanine, 2-(benzyloxycarbonylamino)ethyl amide

Participants

Reaction Steps

A solution of 12.0 g (0.033 mol) of (1g) in 25 ml of dichloromethane was cooled with an ice bath and 25 ml of trifluoroacetic acid was added. The solution was stirred at ca 5° C. for 20 minutes, then allowed to stir to room temperature. After 90 minutes, the dichloromethane and trifluoroacetic acid were removed in vacuo. The resulting residue was dissolved in 200 ml of ethyl acetate and washed with 2M sodium hydroxide (200 ml) and brine (100 ml). After drying over anhydrous magnesium sulfate, the solution was filtered and concentrated in vacuo to produce 7.86 g (90% yield) of L-alanine, 2-(benzyloxycarbonylamino)ethyl amide (1h) as a white solid. 1H NMR (CDCl3) δ 1.28(d, 3H), 2.09(m, 2H), 3.33(m, 4H), 3.47(q, 1H), 5.07(s, 2H), 5.59(bt, 1H), 7.33(bs, 5H), 7.69(bt, 1H); 13C NMR (CDCl3) δ 21.3, 39.5, 40.9, 50.4, 66.6, 128.0, 128.1, 128.4, 136.4, 156.9, 176.7.

Provenance & Evidence