catalyst, the phasetransfercatalyzedmethod of oxidation of primary amines to symmetricalazobenzenes with a saturated solution of potassium ferricyanide in 2N aqueous potassium hydroxide and dichloromethane is described for the first time in this paper. The reaction has intimate relation with Hammett substituent constants. This report offers an efficient and rapid method to prepareazobenzenes and a possible
作者:Shire Elmi、Per Heggen、Bjarte Holmelid、Didrik Malthe-Sørensen、Leiv K. Sydnes
DOI:10.1080/00304948.2016.1206425
日期:2016.9.2
conditions 2a was not formed at all and a complex product mixture was obtained from which the only reasonably pure product isolated in low yield (4%) was 2,20,4,40-tetramethylazobenzene (3a). The iodination of benzene derivatives is influenced by the nature of the substituents. It was therefore of interest to investigate the reaction of some activated and deactivated aniline derivatives under the conditions
Convenient Electrocatalytic Synthesis of Azobenzenes from Nitroaromatic Derivatives Using SmI<sub>2</sub>
作者:Yu-Feng Zhang、Mohamed Mellah
DOI:10.1021/acscatal.7b02940
日期:2017.12.1
The synthesis of azobenzenes has been a long-standing challenge. Their current preparation at a preparative or industrial scale requires stoichiometric amounts of environmentally unfriendly reactants. Herein, we demonstrate that the catalytic use of electrogenerated samarium diiodide (SmI2) could promote, in one-step synthesis, the reduction of nitrobenzenes into azobenzenes in high yields under mild
Rhodium(III)-Catalyzed Synthesis of Cinnolinium Salts from Azobenzenes and Diazo Compounds
作者:Xiaohong Chen、Guangfan Zheng、Guoyong Song、Xingwei Li
DOI:10.1002/adsc.201800326
日期:2018.8.6
A Rh(III)‐catalyzed C−H activation of azobenzenes in the coupling with diazo compounds has been realized, providing a straightforward strategy to access functionalized cinnolinium triflates in high yields. This protocol features silver free mild reaction conditions and compatibility with diverse functional groups. The coupling proceeds via initial Rh(III)‐catalyzed C−H alkylation, followed by zinc
One-pot Synthesis of Oxindoles through C−H Alkylation and Intramolecular Cyclization of Azobenzenes with Internal Olefins
作者:Sang Hoon Han、Neeraj Kumar Mishra、Hyeim Jo、Yongguk Oh、Mijin Jeon、Saegun Kim、Woo Jung Kim、Jong Suk Lee、Hyung Sik Kim、In Su Kim
DOI:10.1002/adsc.201700147
日期:2017.7.17
as maleimides, maleates and fumarates, followed by reductiveintramolecularcyclization is described. A cationic rhodium catalyst in the presence of acetic acid additive in dichloroethane solvent was found to be the optimal catalytic system for the construction of ortho‐alkylated azobenzenes, which smoothly underwent the intramolecularcyclization leading to the formation of C3‐functionalized oxindoles