反应详情

20 g (98.4 mmol)of 3-benyloxyaniline, 12.6 ml (0.984 mmol) of ethyl acetoacetate and 0.189 g (1 mmol) of p-toluenesulfonic acid monohydrate in 32 ml of cyclohexane were heated at reflux for 5.5 h in the presence of a water separator funnel. The reaction mixture was cooled to RT, some solid material was filtered off by suction and the filtrate was concentrated in vacuo to give 30.6 g (99%) of the desired 3-(3-benzyloxy-phenylamino)-but-2-enoic acid ethyl ester as a yellow oil. This was used without further purification in the next reaction step.

1. filtrationsome solid material was filtered off by suction
2. concentrationthe filtrate was concentrated in vacuo