A Silicon-Centred Tetrafunctionalised Reagent for the Cyclopropylmethylsilane-Terminated Prins Reaction and a Concise Synthesis of Lyngbic Acid
作者:D. Braddock、Ai Matsuno
DOI:10.1055/s-2004-834802
日期:——
A novel silicon-centred tetrafunctionalised reagent, tetra(2-ethenylcyclopropylmethyl)silane, has been prepared as a mixture of all possible 19 diastereoisomers. It reacts with TMSOTf-activated acetals via initial Prins reaction of the olefin and 'termination' by the cyclopropylmethylsilane groups. In this manner it smoothly transfers three of its groups to form skipped diene ether products. The reaction
一种新型的以硅为中心的四官能化试剂,四(2-乙烯基环丙基甲基)硅烷,已制备为所有可能的 19 种非对映异构体的混合物。它通过烯烃的初始 Prins 反应和环丙基甲基硅烷基团的“终止”与 TMSOTf 活化的缩醛反应。以这种方式,它平稳地转移三个基团以形成跳过的二烯醚产品。该反应在立体电子控制下,并且无论每个反应的乙烯基环丙烷的初始顺式/反式构型或硅烷中其他乙烯基环丙烷基团的相对构型如何,都只得到 E 跳过的二烯。该试剂的合成效用通过其在海洋天然产物灵比酸的简洁合成中的使用得到了证明。