Hydrogen peroxide based oxidation of hydrazines using HBr catalyst
作者:Jian Wang、Zichao Ma、Wanting Du、Liming Shao
DOI:10.1016/j.tet.2021.132546
日期:2021.12
Azo compounds (RN = NR′) are an important class of organic molecules that find wide application in organic synthesis. Herein, we report an efficient, practical and metal-free oxidation of hydrazines (RNH-NHR’) to azo compounds using 5 mol% HBr and hydrogen peroxide as terminal oxidant. This new method has been demonstrated by 40 examples with excellent yields. In addition, we showcased two examples
Aerobic Oxidation of Alkyl 2-Phenylhydrazinecarboxylates Catalyzed by CuCl and DMAP
作者:Min Hye Kim、Jinho Kim
DOI:10.1021/acs.joc.7b03119
日期:2018.2.2
various fruitful organic reactions such as a catalytic Mitsunobu reaction were reported by virtue of alkyl 2-phenylazocarboxylates, however, the synthesis of alkyl 2-phenylazocarboxylates largely depended on the stoichiometric use of toxic oxidants. In this manuscript, an environment-friendly aerobic oxidative transformation of alkyl 2-phenylhydrazinecarboxylates to alkyl 2-phenylazocarboxylates is
A RhIII‐catalyzed C–H activation/cyclativecaptureapproach, involving a nucleophilic addition of C(sp3)–Rh species to polarized double bonds is reported. This constitutes the first intermolecular catalytic method to directly access 1‐aminoindolines with a broad substituent scope under mild conditions.
Synthesis of Cinnolines and Cinnolinium Salt Derivatives by Rh(III)-Catalyzed Cascade Oxidative Coupling/Cyclization Reactions
作者:Yanwei Wang、Bin Li、Baiquan Wang
DOI:10.1021/acs.joc.8b01548
日期:2018.9.21
A novel method for the synthesis of cinnolines and cinnolinium salt derivatives via Rh(III)-catalyzed cascade oxidative coupling/cyclizationreaction from Boc-arylhydrazines and alkynes has been developed. The reactions have a broad substrate scope and high stereoselectivity with readily available starting materials and provides an efficient synthetic route for this kind of compounds. A catalytically
A redox‐neutral cobalt(III)‐catalyzed synthetic approach for the direct synthesis of unprotected indoles showcasing an N−Nbondcleavage is reported. The herein newly introduced Boc‐protected hydrazines establish a beneficial addition to the limited portfolio of oxidizing directing groups for cobalt(III) catalysis. Moreover, the developed catalytic methodology tolerates a good variety of functional