Lewis Acid Catalyzed Intramolecular Diels−Alder Reactions of Acyclic (<i>Z</i>)-Substituted 1,3-Dienes
作者:Neal A. Yakelis、William R. Roush
DOI:10.1021/ol015667k
日期:2001.3.1
Lewis acid catalyzed intramolecular Diels-Alder reactions of trienes (E,E,Z)-1a-d, (E,E,Z)-4a-d, and (E,Z,Z)-7a,b are described. Trienes containing enal or enone dienophiles cyclize in excellent yield under mild conditions using substoichiometric amounts of MeAlCl(2), in most cases with high levels of diastereoselectivity. The thermal IMDA reactions of 1a, 4a, and 7a require forcing conditions and
描述了路易斯酸催化的三烯(E,E,Z)-1a-d,(E,E,Z)-4a-d和(E,Z,Z)-7a,b的分子内Diels-Alder反应。在大多数情况下,非对映选择性很高的情况下,使用亚化学计量的MeAlCl(2),在温和的条件下,含有烯或烯双烯亲二烯的三烯以优异的产率环化。1a,4a和7a的IMDA热反应需要强制条件,在1a和4a的情况下,产率低且立体选择性相反。