Pauson–Khand reactions of functionalized allenes with different alkynes give cyclopentenones with generally high regio- and stereoselectivities. The allenes react through their external double bonds, giving cyclopentenones with exocyclic double bond at their β positions and predominantly with E stereochemistry. Some intramolecularreactions with allenynes connected through aromatic rings are described
具有不同炔烃的官能化丙二烯的 Pauson-Khand 反应产生具有通常高区域选择性和立体选择性的环戊烯酮。丙二烯通过它们的外部双键反应,得到在其 β 位置具有环外双键的环戊烯酮,主要是 E 立体化学。描述了通过芳环连接的丙炔的一些分子内反应。这些以中等至良好的产率得到相应的杂环。
Photocatalytic Metal Hydride Hydrogen Atom Transfer Mediated Allene Functionalization by Cobalt and Titanium Dual Catalysis
作者:Huaipu Yan、Qian Liao、Yuqing Chen、Gagik G. Gurzadyan、Binghui Lu、Chao Wu、Lei Shi
DOI:10.1002/anie.202302483
日期:2023.6.12
Reported is on the photo Co metal hydride hydrogen atom transfer (MHAT) reaction for chemoselective allene functionalization by using Co-porphines as catalysts and the Hantzsch ester as an H atom and electron donor. The merger of Co MHAT and Ti catalysis under photoredox conditions enabled successful carbonyl allylation, providing access to valuable β-functionalized homoallylic alcohols with exceptional
报道了通过使用 Co-卟啉作为催化剂和 Hantzsch 酯作为 H 原子和电子供体,用于化学选择性丙二烯功能化的照片 Co 金属氢化物氢原子转移 (MHAT) 反应。在光氧化还原条件下,Co MHAT 和 Ti 催化的结合使羰基烯丙基化反应成功,为获得具有特殊区域选择性和非对映选择性的有价值的 β-官能化高烯丙醇提供了途径。