Synthesis of Chiral N-Heterocyclic Allylboronates via the Enantioselective Borylative Dearomatization of Pyrroles
Synthesis of Chiral N-Heterocyclic Allylboronates via the Enantioselective Borylative Dearomatization of Pyrroles
复制标题
DOI：
10.1021/acs.orglett.9b04581
复制
发表时间：
2020-01-17
期刊：
影响因子：
5.2
通讯作者：
Ito, Hajime
中科院分区：
文献类型：
--
作者：
Hayama, Keiichi;Kojima, Ryoto;Ito, Hajime
以吡咯为原料，在铜（I）催化下，通过C-B键形成脱芳构化反应，首次实现了五元N-杂环烯丙基硼酸酯的不对称选择性合成。该反应包括硼基铜（I）物种与吡咯-2-羧酸酯的区域选择性和对映选择性加成，然后将所得烯醇化铜（I）非对映选择性质子化，得到吡咯烷型烯丙基硼酸酯。该产品是非常有吸引力的试剂，用于通过随后的烯丙基硼化/氧化过程快速构建具有五个连续立体中心的吡咯烷衍生物。
The first enantioselective synthesis of five-membered N-heterocyclic allylboronates has been accomplished by a C-B bond-forming dearomatization of pyrroles using a copper(I) catalyst. This reaction involves the regio- and enantioselective addition of a borylcopper(I) species to pyrrole-2-carboxylates, followed by the diastereoselective protonation of the resulting copper(I) enolate to afford pyrrolidine-type allylboronates. The products are highly attractive reagents for the rapid construction of pyrrolidine derivatives that bear five consecutive stereocenters via subsequent allylboration/oxidation processes.