Michael reactions followed by a retro Diels-Alder cleavage convert the optically active tricyclic lactol 1 into 2-substituted 2.5-dihydrofurans of high enantiomeric purities. These compounds are useful synthons for the obtention of natural butenolides and butanolides as illustrated by the synthesis of the pheromone (+)-eldanolide.
立体选择性串联Wittig-Horner-分子内迈克尔反应,然后进行逆向Diels-Alder裂解,将光学活性的
三环乳醇1转化为高对映体纯度的2-取代的2.5-二氢
呋喃。这些化合物是有用的合成子,用于获得天然的
丁烯内酯和
丁醇化物,如信息素(+)-艾丹醇化物的合成所示。