Phosphine-Catalyzed (3 + 2)/(3 + 2) Sequential Annulation of γ-Vinyl Allenoates: Access to Fused Carbocycles
作者:Jiaxu Feng、Yingying Chen、Wenhui Qin、You Huang
DOI:10.1021/acs.orglett.9b04176
日期:2020.1.17
The first (3 + 2)/(3 + 2) sequential annulation of γ-vinyl allenoates with alkylidenemalononitriles enabled by phosphine catalysis has been reported. A broad range of structurally dense tetra- and penta-substituted bicyclic[3,3,0]octene derivatives, containing a quaternary center and three sequential stereogenic center, were synthesized in good to excellent yields. In this approach, three new C-C bonds
据报道,通过膦催化,首次(3 + 2)/(3 + 2)依次使γ-乙烯基烯丙基酯与亚烷基丙二腈成环。合成了范围广泛的结构稠密的四和五取代双环[3,3,0]辛烯衍生物,其中包含一个季中心和三个连续的立体异构中心,收率良好至极佳。在这种方法中,在一个罐中形成了三个新的CC键,γ-乙烯基脲酸的εC和αC是两个亲电中心,而其γC则表现出亲核反应性。