Claisen 重排是人们熟知的经典反应,可表示如右.底物中的氧原子被氮子代替以后的按(N)-Claisen重排,机量与O_Claisen重排相似,但因活化能高,重排较难进行故直到1961年才发现.经过20多年的研究,至今已有许多例子获得成功.本文主要就其在合成方面的意义,进行介绍. Claisen rearrangement is a well-known classical reaction and can be represented as right Substitution of oxygen atoms in the substrate by (N) -Claisen rearrangement by nitrogen instead of oxygen is similar to that of O_Claisen rearrangement but due to high activation energy, Rearrangement is more difficult to be discovered until 1961. After more than 20 years of research, so far, many examples have been successful.This paper mainly on the significance of its synthesis, are introduced.