反应详情

19.8 ml (168 mmol) of diethylene glycol monomethyl ether are added dropwise at 0° to 100 ml of a 20% solution of phosgene in toluene and the mixture is stirred overnight at RT. Excess phosgene is expelled with nitrogen and the reaction solution is washed with water and concentrated by evaporation. Analogously to Example 1c, 10 g (85.4 mmol) of (L)-valine are added to the crude 2-(2-methoxyethoxy)ethylchloroformate (15.6 g, 85.4 mmol) yielding the title compound in the form of a colourless resin. 1H-NMR (200 MHz, CD3OD): 4.18 (m, 2H), 4.05 d, J=6 Hz, 1H), 3.72-3.40 (m, 8H), 3.35 (s, 3H), 2.18 (m, 1H), 0.95 (t, J=7H, 6H).

1. washthe reaction solution is washed with water
2. concentrationconcentrated by evaporation