This report describes a palladium-catalyzed Catellani reaction consisting of amination/[2 + 3] or [2 + 4] cyclization via a carboxylate ligand-exchange strategy. This method effectively activates ortho-substituents that avoid a second C–H palladation. The scope of substrates was broad, o-methyl-substituted iodoarenes were applied to the reaction smoothly, and o-phenyl-substituted iodoarenes can also
Starting from cyclic diaryliodoniums and terminal alkenes, a diverse set of fluorenes is conveniently constructed. The reactions catalyzed by palladium undergo one conventional Mizoroki‐Heckreaction and one reductive Heckreaction. The scope of alkenes is general, leading to 29 fluorenes which would expand the structural diversity of fluorene reservoir.
Scalable electrochemical synthesis of diaryliodonium salts
作者:Mohamed Elsherbini、Wesley J. Moran
DOI:10.1039/d1ob00457c
日期:——
Cyclic and acyclic diaryliodonium are synthesised by anodic oxidation of iodobiaryls and iodoarene/arene mixtures, respectively, in a simple undivided electrolysis cell in MeCN–HFIP–TfOH without any added electrolyte salts. This atom efficient process does not require chemical oxidants and generates no chemical waste. More than 30 cyclic and acyclic diaryliodoniumsalts with different substitution
环状和非环状二芳基碘鎓分别通过碘联芳基和碘代芳烃/芳烃混合物的阳极氧化合成,在 MeCN-HFIP-TfOH 的简单未分隔电解池中,不添加任何电解质盐。这种原子效率的过程不需要化学氧化剂,也不会产生化学废物。以非常好的收率制备了 30 多种具有不同取代模式的环状和非环状二芳基碘鎓盐。将反应放大至 10 mmol 规模,在不到 3 小时内得到超过 4 克的二苯并[ b , d ]碘-5-鎓三氟甲磺酸盐 (>95%)。大规模实验的溶剂混合物被回收(>97%)并循环多次,收率没有显着降低。
Palladium-catalyzed C–H bond activation for the assembly of <i>N</i>-aryl carbazoles with aromatic amines as nitrogen sources
作者:Xiaobing Liu、Heyun Sheng、Yao Zhou、Qiuling Song
DOI:10.1039/c9cc09493h
日期:——
A convenient and efficient palladium-catalyzedC-Hbondactivation for the assembly of N-aryl carbazole is reported, in which two C-N bonds were formed under one set of conditions. The desired carbazoles were achieved in decent yields with a wide substrate scope by utilizing readily available 2-iodo biphenyls and aromatic amines as starting materials.
diaziridinone under palladium catalysis. A wide range of carbazoles were synthesized in good to excellent yields, and indolederivatives were obtained by using styrenes as the substrate. The palladacycles obtained from 2‐iodobiphenyls acted as the key intermediate, and the reaction should proceed via a tandem Pd‐catalyzedC−Hactivation/dual C−N bond formation sequence.