One‐Pot Synthesis of Metastable 2,5‐Dihydrooxepines through Retro‐Claisen Rearrangements: Method and Applications
作者:Wei Zhang、Emmanuel Baudouin、Marie Cordier、Gilles Frison、Bastien Nay
DOI:10.1002/chem.201901675
日期:2019.6.26
synthesize metastable bicyclic 2,5‐dihydrooxepines from cyclic 1,3‐diketones and 1,4‐dibromo‐2‐butenes through the retro‐Claisen rearrangement of syn‐2‐vinylcyclopropyl diketone intermediates is reported. DFT calculations were performed to understand the reaction selectivity and mechanisms towards [1,3]‐ or [3,3]‐sigmatropic rearrangements, highlighting the crucial influence of the temperature. The reaction
报道了一种通过一锅法从环状1,3-二酮和1,4-二溴-2-丁烯通过顺-2-乙烯基环丙基二酮中间体的反向克莱森重排合成亚稳的双环2,5-二氢氧杂环丁烷的方法。进行DFT计算是为了了解对[1,3]-或[3,3]-σ重排的反应选择性和机理,突出了温度的关键影响。该反应已成功应用于radulanin A(一种天然的2,5-二氢苯并xepine)的无保护基团的短合成。此外,首次证明了这种天然产品具有很强的除草潜力。