6-Fumaryl 1,3,8-nonatrienes substituted at the C5 position by a vinyl group were found to undergo competing tandem sigmatropic rearrangement/Diels–Alder cyclisation when heated under standard Diels–Alder cyclisation conditions. This rearrangement became the exclusive pathway when the reactions were performed in the presence of a Lewis acid.
在标准Diels-Alder环化条件下加热时,发现在C 5位置被
乙烯基取代的6-Fumaryl 1,3,8-壬二烯会发生竞争性的串联σ重排/ Diels-Alder环化。当在
路易斯酸的存在下进行反应时,这种重排成为排他性途径。