Melekhov A, Forgione P, Legoupy S, Fallis A G
Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, Canada K1N 6N5.
Org Lett. 2000 Sep 7;2(18):2793-6. doi: 10.1021/ol0062042.
[reaction: see text] The beneficial influence of cis-isopropylidene acetal tether control groups, to facilitate the asymmetric synthesis of substituted decalins by intramolecular Diels-Alder reactions, is described. Compared to trans-acetonides, these cases proceed under milder conditions to afford the cis-fused adducts from an endo transition state. An unusual acetonitrile solvent effect exerts a dramatic influence on the diastereoselectivity. This strategy leads to the chiral nonracemic bicyclo[4.4.0]decane core of diverse natural products.
[反应：见正文] 描述了顺式异亚丙基缩醛连接控制基团在通过分子内狄尔斯-阿尔德反应促进取代十氢化萘的不对称合成中的有益影响。与反式缩酮相比，这些情况在更温和的条件下进行，从内型过渡态得到顺式稠合加合物。一种不寻常的乙腈溶剂效应会对非对映选择性产生显著影响。该策略可得到多种天然产物的手性非外消旋双环[4.4.0]癸烷核心结构。
