Carbocyclic construction by the [2,3]sigmatropic rearrangement of cyclic sulfonium ylides. a new entry for the stereoselective synthesis of substituted cyclohexanones
作者:Fusao Kido、Kazuo Yamaji、Subhash C. Sinha、Toshiya Abiko、Michiharu Kato
DOI:10.1016/0040-4020(95)00409-2
日期:1995.7
The rhodium(II)-catalyzed cyclization of acyclic α-diazo-β-keto esters 1c,d provided stereoselectively the highly substituted cyclohexanones 3c,d respectively, by the [2,3]sigmatropic rearrangement via stereocontrolled nine-membered allylsulfonium ylides 2c,d. Further elaboration of 3d toward the cyclohexanone 36 accomplished asymmetric formal syntheses of the representative elemanoids, 37 and 38.
铑(II)催化的无环α-重氮-β-酮酸酯1c,d的环化反应是通过立体控制的九元烯丙基ulf化萘2c通过[2,3]σ重排,分别立体选择性地提供了高度取代的环己酮3c,d 。 d。朝环己酮36进一步进行3d修饰,完成了代表性电子体37和38的不对称形式合成。化合物3c被转化为环己酮34a和环己烯43可以用作合成天然产物的关键中间体,这些天然产物分别具有连续的顺式排列的三甲基环己酮及其相关部分。