Reductive Radical Annulation Strategy toward Bicyclo[3.2.1]octanes: Synthesis of <i>ent</i>-Kaurane and Beyerane Diterpenoids
作者:Junming Zhuo、Chunlin Zhu、Jinbao Wu、Zijian Li、Chao Li
DOI:10.1021/jacs.1c11623
日期:2022.1.12
Here we report a general [3 + 2] radical annulation that allows the facile construction of bicyclo[3.2.1]octane motifs in ent-kaurane- and beyerane-type diterpenoids. This radical annulation is difficult to control but was realized by harnessing an unprecedented and counterintuitive effect of TEMPO. Eleven natural products with a wide array of oxidation states are easily prepared, demonstrating the
The garryfoline–cuauchichicine rearrangement: a study of the mechanism in the (–)-kaurenols
作者:M. F. Barnes、J. MacMillan
DOI:10.1039/j39670000361
日期:——
The mechanism of the garryfoline–cuauchichicinerearrangement has been investigated using the epimeric (–)-kaur-16-en-15-ols as models. The 15β-ol is shown to rearrange rapidly in mineral acid at room temperature to 16R-(–)-kaur-15-one by a 15,16-hydride shift. The 16α-ol, like veatchine, is stable under these conditions. The contrast in the ability of these epimeric alcohols to undergo 15,16-hydride
已经使用差向异构(-)-kaur-16-en-15-ols作为模型研究了garryfoline–cuauchichicine重排的机制。研究表明,在室温下,无机酸中的15β-ol可通过15,16-氢化物移位迅速重排为16 R -(-)-kaur-15-。像veatchine一样,16α-ol在这些条件下也是稳定的。讨论了这些差向异构醇经历15,16-氢化物转变的能力的对比。