92846-10-1Relevant academic research and scientific papers
Hydrogen peroxide based oxidation of hydrazines using HBr catalyst
Du, Wanting,Ma, Zichao,Shao, Liming,Wang, Jian
, (2021/11/18)
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 of the one-pot sequential reactions involving our hydrazine oxidation/hydrolysis/Heck reaction or Cu-catalyzed N-arylation with aryl boronic acid. The distinct advantages of this protocol include metal-free catalysis, waste prevention, and easy operation.
Selective Functionalization of Graphene at Defect-Activated Sites by Arylazocarboxylic tert-Butyl Esters
Halbig, Christian E.,Lasch, Roman,Krüll, Jasmin,Pirzer, Anna S.,Wang, Zhenping,Kirchhof, Jan N.,Bolotin, Kirill I.,Heinrich, Markus R.,Eigler, Siegfried
supporting information, p. 3599 - 3603 (2019/02/01)
The development of versatile functionalization concepts for graphene is currently in the focus of research. Upon oxo-functionalization of graphite, the full surface of graphene becomes accessible for C?C bond formation to introduce out-of-plane functional
Aerobic Oxidation of Alkyl 2-Phenylhydrazinecarboxylates Catalyzed by CuCl and DMAP
Kim, Min Hye,Kim, Jinho
, p. 1673 - 1679 (2018/02/09)
Recently, 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 disclosed. The use of CuCl and DMAP system efficiently catalyzed the aerobic oxidation of alkyl 2-phenylhydrazinecarboxylates under mild conditions. The reaction rate of the present Cu-catalysis was much faster than that of the previously reported Fe-catalysis, and a variety of azo products were synthesized within 3 h. The present protocol was effective on larger scale. It was observed that the produced azo compound could undergo various reactions without isolation through one-pot sequential protocols.
Cycloaddition reactions of glycine imine anions to phenylazocarboxylic esters - A new access to 1,3,5-trisubstituted 1,2,4-triazoles
Lasch, Roman,Heinrich, Markus R.
, p. 4282 - 4295 (2015/06/08)
Phenylazocarboxylic tert-butyl esters have recently been shown to be highly versatile building blocks due to their ability to undergo nucleophilic aromatic substitutions under mild conditions, particularly well with [18F]fluoride, and to act as precursors for aryl radicals. In this article, we now report first examples for cycloaddition reactions to phenylazocarboxylates. In a one-pot reaction with readily accessible glycine imines, a variety of highly substituted 1,2,4-triazoles could be obtained.
Rhodium(III)-catalyzed cyclative capture approach to diverse 1-aminoindoline derivatives at room temperature
Zhao, Dongbing,Vsquez-Cspedes, Suhelen,Glorius, Frank
supporting information, p. 1657 - 1661 (2015/01/30)
A RhIII-catalyzed C-H activation/cyclative capture approach, 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.
