Transition-Metal-Free Cross-Coupling Reactions in Dynamic Thin Films To Access Pyrimidine and Quinoxaline Analogues
作者:Louisa A. Ho、Colin L. Raston、Keith A. Stubbs
DOI:10.1002/ejoc.201600830
日期:2016.12
The vortex fluidic device (VFD) is effective in modulating the synthesis of pyrimidine and quinoxaline-based compounds at room temperature and in high yield. The formation of the C–N bond occurs in the absence of a transition-metal catalyst, which avoids the contamination of the products with trace amounts of a transition metal. The systematic investigation of the operating parameters for the microfluidic
Amination of Heteroaryl Chlorides: Palladium Catalysis or S<sub>N</sub>Ar in Green Solvents?
作者:Katie Walsh、Helen F. Sneddon、Christopher J. Moody
DOI:10.1002/cssc.201300239
日期:2013.8
reaction of heteroarylchlorides in the pyrimidine, pyrazine and quinazoline series with amines in water in the presence of KF results in a facile SNAr reaction and N‐arylation. The reaction is less satisfactory with pyridines unless an additional electron‐withdrawing group is present. The results showed that the transition‐metal‐free SNAr reaction not only compares favourably to palladium‐catalysed
嘧啶、吡嗪和喹唑啉系列中的杂芳基氯化物与水中的胺在 KF 存在下发生反应,导致容易的 S N Ar 反应和N芳基化。除非存在额外的吸电子基团,否则吡啶的反应不太令人满意。结果表明,无过渡金属的 S N Ar 反应不仅优于钯催化的偶联反应,而且在碱和溶剂方面也可以在环境可接受的(“绿色”)条件下进行。
Copper-catalyzed, ceric ammonium nitrate mediated <i>N</i>-arylation of amines
作者:Uma Maheshwar Gonela、Seth Y. Ablordeppey
DOI:10.1039/c8nj06145a
日期:——
reported. This 'Chan-Evans-Lam' reaction has revealed that at room temperature, catalytic copper(II) acetate and cericammoniumnitrate (CAN) as an oxidant, N-arylation can result in an effective C-N bond formation. This air stable, practical, robust protocol enables a variety of functional group tolerance on both boronic acid and amine partners.
AbstractA new class of large‐but‐flexible Pd‐BIAN‐NHC catalysts (BIAN=acenaphthoimidazolylidene, NHC=N‐heterocyclic carbene) has been rationally designed to enable the challenging Buchwald‐Hartwig amination of coordinating heterocycles. This robust class of BIAN‐NHC catalysts permits cross‐coupling under practical aerobic conditions of a variety of heterocycles with aryl, alkyl, and heteroarylamines, including historically challenging oxazoles and thiazoles as well as electron‐deficient heterocycles containing multiple heteroatoms with BIAN‐INon (N,N′‐bis(2,6‐di(4‐heptyl)phenyl)‐7H‐acenaphtho[1,2‐d]imidazol‐8‐ylidene) as the most effective ligand. Studies on the ligand structure and electronic properties of the carbene center are reported. The study should facilitate the discovery of even more active catalyst systems based on the unique BIAN‐NHC scaffold.