Pérez Sestelo J, Real M M, Sarandeses L A
Departamento de Química Fundamental, Universidade da Coruña, E-15071 A Coruña, Spain.
J Org Chem. 2001 Feb 23;66(4):1395-402. doi: 10.1021/jo0015319.
A Diels-Alder reaction of novel inner-outer-ring 1,3-silyloxydienes 5-8 with a variety of dienophiles to afford highly functionalized polycyclic structures is reported. The inner-outer-ring 1,3-silyloxydienes 5-8 containing five- to seven-membered carbocyclic and heterocyclic rings were prepared in a single reaction vessel from 2-acetylcyclocarbonyls in quantitative yields. The Diels-Alder reaction with 1,4-benzoquinone (BQ), dimethyl acetylenedicarboxylate (DMAD), and methyl vinyl ketone (MVK) proceeded smoothly at room temperature, affording functionalized polycyclic naphthols, phenols, and enones with high regioselectivity and good yields (39-75%). Moreover, dienes 5-8 also reacted in a hetero-Diels-Alder reaction with benzaldehyde (BA) and N-benzylideneaniline (NBA) in the presence of catalytic amounts of ZnCl2, affording substituted polycyclic pyranones and pyridinones in good yields (40-93%). Overall, our synthetic strategy provides straightforward access to an interesting set of polycyclic structures useful for natural and nonnatural product synthesis.
报道了新型内外环1,3-硅氧基二烯5-8与多种亲双烯体的狄尔斯-阿尔德反应，以提供高度官能化的多环结构。含有五至七元碳环和杂环的内外环1,3-硅氧基二烯5-8在单个反应容器中由2-乙酰基环羰基化合物定量制备。与1,4-苯醌（BQ）、二甲基乙炔二羧酸酯（DMAD）和甲基乙烯基酮（MVK）的狄尔斯-阿尔德反应在室温下顺利进行，以高区域选择性和良好产率（39-75%）得到官能化的多环萘酚、酚和烯酮。此外，二烯5-8在催化量的ZnCl2存在下也与苯甲醛（BA）和N-苄叉苯胺（NBA）发生杂狄尔斯-阿尔德反应，以良好产率（40-93%）得到取代的多环吡喃酮和吡啶酮。总体而言，我们的合成策略为用于天然和非天然产物合成的一组有趣的多环结构提供了直接的途径。
