Remote Asymmetric Induction in Lewis Acid-Catalyzed Diels-Alder Reaction of .ALPHA.,.BETA.-Unsaturated Enones Having a Chiral Sulfinyl-Substituted, 5-Membered Aromatic Heterocycle.
作者:Yoshitsugu ARAI、Tsutomu MASUDA、Yukio MASAKI
DOI:10.1248/cpb.46.1078
日期:——
Two types of chiral sulfoxides as Diels-Alder dienophiles were synthesized and high levels of diastereoselectivity were observed in cycloadditions. 2-Furyl and 2-thienyl α, β-enones, bearing a chiral sulfinyl group in the heterocycle, served as efficient dienophiles in Diels-Alder reactions, where the catalytic use of aluminium chloride or a lanthanide triflate effected the cycloaddition with cyclopentadiene affording the endo adduct with high diastereoselectivity, ranging from 91% to 98%.
合成了两种手性硫醚作为 Diels-Alder 亲二烯化合物,并在环加成反应中观察到了高水平的非对映选择性。杂环中带有手性亚磺酰基的 2-呋喃基和 2-噻吩基 α、β-烯酮在 Diels-Alder 反应中可作为高效的亲二烯,在这种反应中,使用氯化铝或三镧系元素催化环戊二烯的环加成反应,生成的内加成物具有很高的非对映选择性,从 91% 到 98%不等。