952-53-4Relevant articles and documents
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.
Synthesis of 2-Imino-1,3,4-Selenadiazoles via Tributylphosphine-Mediated Annulation of N-Aroyldiazenes with Isoselenocyanates
Huang, Zhengyan,Zhang, Qianqian,Yi, Xiaofei,Zhao, Zongxiang,Yu, Wenquan,Chang, Junbiao
supporting information, p. 4894 - 4898 (2021/09/14)
2-Imino-1,3,4-selenadiazole derivatives can be synthesized from hydrazides and isoselenocyanates by sequential oxidation and a tributylphosphine (PBu3)-promoted annulation reaction at room temperature. In this synthetic process, crude less stab
Synthesis of 2-Imino-1,3,4-Thiadiazoles from Hydrazides and Isothiocyanates via Sequential Oxidation and P(NMe2)3-Mediated Annulation Reactions
Huang, Zhengyan,Zhang, Qianqian,Zhao, Qiongli,Yu, Wenquan,Chang, Junbiao
supporting information, p. 4378 - 4382 (2020/06/03)
A P(NMe2)3-mediated annulation reaction of N-Acyldiazenes with isothiocyanates, producing 2-imino-1,3,4-Thiadiazoles, is reported. This reaction proceeds well with crude N-Acyldiazenes derived from the oxidation of hydrazides by iodi
Annulation Reactions of In-Situ-Generated N-(Het)aroyldiazenes with Isothiocyanates Leading to 2-Imino-1,3,4-oxadiazolines
Zhao, Qiongli,Ren, Linning,Hou, Jiao,Yu, Wenquan,Chang, Junbiao
supporting information, p. 210 - 213 (2019/01/04)
A novel annulation reaction of N-(het)aroyldiazenes and isothiocyanates has been established. This transformation involves a sequential cyclization and desulfurization/intramolecular rearrangement to produce 2-imino-1,3,4-oxadiazolines. The less-stable N-(het)aroyldiazenes can be conveniently generated in situ by I2-mediated oxidation of hydrazides, which allows a one-pot synthesis of the products directly from readily accessible hydrazide and isothiocyanate substrates. This operationally simple synthetic process requires no use of malodorous isocyanides and can be conveniently conducted on a gram scale.
Electrochemical dehydrogenation of hydrazines to azo compounds
Du, Ke-Si,Huang, Jing-Mei
supporting information, p. 1680 - 1685 (2019/04/08)
A strategy for the electrochemical dehydrogenation of hydrazine compounds is disclosed under ambient conditions. This protocol proceeded smoothly in ethanol by employing electrons as clean oxidants. Its synthetic value is well demonstrated by the highly efficient synthesis of symmetric and unsymmetric azo compounds. It is an environmentally friendly transformation and the present protocol was effective on a large scale.
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.
Easy and rapid preparation of benzoylhydrazides and their diazene derivatives as inhibitors of 15-lipoxygenase
Tirapegui, Cristian,Acevedo-Fuentes, Williams,Dahech, Pablo,Torrent, Claudia,Barrias, Pablo,Rojas-Poblete, Macarena,Mascayano, Carolina
, p. 1649 - 1653 (2017/04/04)
Two series of diaza derivatives were prepared by solvent-free condensation of benzoic acid and 4-substituted phenylhydrazines in order to obtain phenylhydrazides (HYD series) and, by oxidation of these compounds, the corresponding benzoyldiazenes (DIA series). Both sets were evaluated as inhibitors of soybean 15-lipoxygenase activity and antioxidant capability in the FRAP and CUPRAC assays. The most potent inhibitors of both series exhibited IC50 values in the low micromolar range. Kinetic studies showed that at least the more active compounds were competitive inhibitors. Docking results indicated that the most potent inhibitor interacts strongly with Ile-839 and iron in the active site.
Preparation of Blatter Radicals via Aza-Wittig Chemistry: The Reaction of N-Aryliminophosphoranes with 1-(Het)aroyl-2-aryldiazenes
Savva, Anastasia C.,Mirallai, Styliana I.,Zissimou, Georgia A.,Berezin, Andrey A.,Demetriades, Marina,Kourtellaris, Andreas,Constantinides, Christos P.,Nicolaides, Constantinos,Trypiniotis, Theodossis,Koutentis, Panayiotis A.
, p. 7564 - 7575 (2017/07/26)
Reacting N-aryliminophosphoranes with 1-(het)aroyl-2-aryldiazenes in preheated diphenyl ether at ca. 150-250 °C for 5-25 min affords in most cases the 1,3-diaryl-1,4-dihydrobenzo[e][1,2,4]triazin-4-yls (aka Blatter radicals) in moderate to good yields. Al
Catalytic Aerobic Oxidation of Arylhydrazides with Iron Phthalocyanine
Hashimoto, Takuma,Hirose, Daisuke,Taniguchi, Tsuyoshi
supporting information, p. 3346 - 3352 (2015/11/03)
A convenient method for the synthesis of 2-arylazocarboxylates from 2-arylhydrazinecarboxylates by aerobic oxidation with iron phthalocyanine is described. The reaction is applicable to oxidative activation of 1-acyl-2-phenylhydrazines. Some preliminary experiments suggest Michaelis-Menten kinetics and participation of radical species in the reaction mechanism.
Asymmetric NHC-catalyzed redox α-amination of α- aroyloxyaldehydes
Taylor, James E.,Daniels, David S. B.,Smith, Andrew D.
, p. 6058 - 6061 (2014/01/06)
Asymmetric α-amination through an N-heterocyclic carbene (NHC)-catalyzed redox reaction of α-aroyloxyaldehydes with N-aryl-N-aroyldiazenes to form α-hydrazino esters with high enantioselectivity (up to 99% ee) is reported. The hydrazide products are readily converted into enantioenriched N-aryl amino esters through samarium(II) iodide mediated N-N bond cleavage.