Bromobutyraldehyde ethylene acetal was synthesized from crotonaldehyde by addition with hydrogen bromide and then acetalation with ethylene glycol with an overall yield of 80.

巴豆醛先与溴化氢加成,再与乙二醇缩醛化得到3-溴代丁醛缩乙二醇,收率80.8%。