Access to Cyclobutene-Fused Azepines through Au-Catalyzed Cycloisomerization of Stable Alkyne Tethered Ketene <i>N,N</i>-Acetals
作者:Sanatan Nayak、Nayan Ghosh、Akhila K. Sahoo
DOI:10.1021/ol501125r
日期:2014.6.6
base promoted reaction between N-protected propargyl amines and 3-bromopropiolate readily provides an array of novel stable alkyne-tethered ketene N,N-acetals in good yields. A wide range of structurally complex cyclobutene-fused azepine heterocycles are synthesized through the gold-catalyzed intramolecular cycloisomerization of ketene N,N-acetals for the first time. A plausible reaction pathway is deduced
N-保护的炔丙基胺和3-溴丙酸酯之间的碱促进的反应容易以良好的产率提供了一系列新型的稳定的炔烃系链烯酮N,N-乙缩醛。首次通过金催化乙烯酮N,N-乙缩醛的分子内环异构化反应,合成了多种结构复杂的环丁烯稠合的ze庚因杂环。根据1 H NMR研究推论出可能的反应途径。
Copper‐Catalyzed Asymmetric Diyne Cyclization via [1,2]‐Stevens‐Type Rearrangement for the Synthesis of Chiral Chromeno[3,4‐
<i>c</i>
]pyrroles
作者:Feng‐Lin Hong、Chong‐Yang Shi、Pan Hong、Tong‐Yi Zhai、Xin‐Qi Zhu、Xin Lu、Long‐Wu Ye
DOI:10.1002/anie.202115554
日期:2022.2.7
copper-catalyzed asymmetric cascade cyclization/[1,2]-Stevens-type rearrangement is disclosed, affording valuable chiral chromeno[3,4-c]pyrroles bearing a quaternary carbon stereocenter in generally moderate to good yields with excellent enantioselectivities. Importantly, this protocol represents the first catalytic asymmetric [1,2]-Stevens-type rearrangement based on alkynes and the first asymmetric formal carbene
公开了一种铜催化的不对称级联环化/[1,2]-Stevens 型重排,以通常中等至良好的产率和优异的对映选择性提供有价值的手性色烯并[3,4- c ]吡咯,其具有季碳立体中心。重要的是,该协议代表了第一个基于炔烃的催化不对称 [1,2]-史蒂文斯型重排和第一个不对称的形式卡宾插入 Si-O 键。