Palladium-Catalyzed Formal Cross-Coupling of Diaryl Ethers with Amines: Slicing the 4-<i>O</i>
-5 Linkage in Lignin Models
作者:Huiying Zeng、Dawei Cao、Zihang Qiu、Chao-Jun Li
DOI:10.1002/anie.201712211
日期:2018.3.26
ether bonds (α‐O‐4, β‐O‐4, and 4‐O‐5 linkages) and other C−C bonds. Among the ether bonds, the bond dissociation energy of the 4‐O‐5 linkage is the highest and the most challenging to cleave. To date, 4‐O‐5 ether linkage model compounds have been cleaved to obtain phenol, cyclohexane, cyclohexanone, and cyclohexanol. The first example of direct formal cross‐coupling of diaryl ether 4‐O‐5 linkage models
作者:Raymond T. Gephart、Daria L. Huang、Mae Joanne B. Aguila、Graham Schmidt、Andi Shahu、Timothy H. Warren
DOI:10.1002/anie.201201921
日期:2012.6.25
A β‐diketiminato copper(I) catalyst enables CHamination of anilines employing low catalyst loadings to preclude oxidation to the diazene ArNNAr (see scheme). Electron‐poor anilines are particularly resistant towards diazene formation and participate in the amination of strong and unactivated CH bonds. N‐alkyl anilines also take part in CHamination.
Palladium-catalyzed reductive coupling of phenols with anilines and amines: efficient conversion of phenolic lignin model monomers and analogues to cyclohexylamines
作者:Zhengwang Chen、Huiying Zeng、Hang Gong、Haining Wang、Chao-Jun Li
DOI:10.1039/c5sc00941c
日期:——
A highly efficient Pd-catalyzed direct coupling of phenolic lignin model monomers and analogues with anilines to give cyclohexylamines using sodium formate as hydrogen donor is described.
N-Alkylation of amines with phenols over highly active heterogeneous palladium hydride catalysts
作者:Long Yan、Xin-Xin Liu、Yao Fu
DOI:10.1039/c6ra22383d
日期:——
secondary amines in considerable yield via hydrogenation and amination tandem reaction over Al2O3 supportedpalladium hydride (PdHx) bi-functional catalyst. Note that this system proceeds efficiently with mild conditions under H2 atmosphere, which was difficult to achieve in previous reports. The catalyst and the mechanism of reaction are both studied. Furthermore, various secondary amines can be formed
通过在Al 2 O 3负载的氢化钯(PdH x)双功能催化剂上进行氢化和胺化串联反应,苯酚以可观的收率直接转化为仲胺。请注意,该系统在H 2气氛中的温和条件下有效运行,这在以前的报告中很难实现。研究了催化剂和反应机理。此外,在该转化体系下可以高产率形成各种仲胺。