furnished the chiral bicyclo[2.2.2]octenones 6, 8 and 9 and 12 and 13 containing a bridgehead methyl group via an intramolecularalkylation reaction. In an analogous manner intramolecularalkylation reaction of the bromo enones 15a–e, obtained from carvone 2 by 1,3-alkylative enone transposition (→14) followed by a regiospecific bromoetherification reaction, furnished the bicyclo[2.2.2]oct-5-en-2-ones
Photochemical Rearrangements of Chiral Bicyclo[2.2.2]oct-5-en-2-Ones<sup>1</sup>
作者:A. Srikrishna、S. Danieldoss
DOI:10.1080/00397919708003339
日期:1997.2
Photochemical oxadi-π-methane rearrangement (1,2-acyl shift) of the chiral bicyclo[2.2.2]oct-5-en-2-ones 2 and 3 furnishes the tricyclic ketones 5 and 6 , whereas the 1,3-acyl shift generates the cyclobutanones 7 and 8 respectively.
Enantioselective Intramolecular Iridium-Catalyzed Cyclopropanation of α-Carbonyl Sulfoxonium Ylides
作者:Lucas Vidal、Pan-Pan Chen、Eva Nicolas、Andrew Hackett、Craig M. Robertson、Kendall N. Houk、Christophe Aïssa
DOI:10.1021/acs.orglett.2c03396
日期:2022.11.25
Enantioselective cyclopropanation of α-carbonyl sulfoxonium ylides (SY) has so far been limited to addition/ring closure reactions on electron-poor olefins. Herein, we report the iridium-catalyzed intramolecular cyclopropanation of SY in the presence of a chiral diene in up to 96% yield and 98% enantioselectivity. Moreover, density functional theory calculations suggest that the re face of the olefin
迄今为止,α-羰基亚砜 (SY) 的对映选择性环丙烷化仅限于缺电子烯烃的加成/闭环反应。在此,我们报道了在手性二烯存在下铱催化的 SY 分子内环丙烷化反应,收率高达 96%,对映选择性高达 98%。此外,密度泛函理论计算表明,烯烃的表面优选在与烯烃的几何结构无关的异步协同步骤中攻击铱卡宾中间体。