反应详情

温度

110 °C

A solution of 5 grams of beta-carbobenzyloxypropionic acid (IV) in 50 ml. of thionyl chloride containing 0.5 ml of anhydrous dimethylformamide is allowed to stand, sheltered from moisture, for two days. The excess thionyl chloride is distilled off under a high vacuum, and the residue, which is a yellow oil, is heated in a flask to 110°C under an abs. pressure of 0.4 mmHg in order to strip the head fractions. The undistilled residue is taken up with ethyl ether, decolorized with charcoal, filtered and concentrated again. There are obtained about 3.48 grams (64% of theory) of (V) which is employed as such for the following stage.

1. distillationThe excess thionyl chloride is distilled off under a high vacuum
2. filtrationfiltered
3. concentrationconcentrated again