25957-94-2Relevant academic research and scientific papers
Synthesis of 3 H-1,2,4-Triazol-3-ones via NiCl2-Promoted Cascade Annulation of Hydrazonoyl Chlorides and Sodium Cyanate
Du, Shiying,Yang, Zuguang,Tang, Jianhua,Chen, Zhengkai,Wu, Xiao-Feng
supporting information, p. 2359 - 2363 (2021/04/05)
A nickel-promoted cascade annulation reaction for the facile synthesis of 3H-1,2,4-triazol-3-ones from readily available hydrazonoyl chlorides and sodium cyanate has been developed. The transformation occurs through a cascade nickel-promoted intermolecular nucleophilic addition-elimination process, intramolecular nucleophilic addition, and a hydrogen-transfer sequence. The method has been successfully applied for the construction of the core skeleton of the angiotensin II antagonist.
[3+2]-cycloaddition of in situ generated nitrile imines and acetylene for assembling of 1,3-disubstituted pyrazoles with quantitative deuterium labeling
Voronin, Vladimir V.,Ledovskaya, Maria S.,Gordeev, Evgeniy G.,Rodygin, Konstantin S.,Ananikov, Valentine P.
, p. 3819 - 3828 (2018/04/14)
A novel synthetic methodology for the preparation of 1,3-disubstituted pyrazoles from in situ generated nitrile imines and acetylene is reported. The reactions are performed in a simple two-chamber reactor. One part of the reactor is loaded with hydrazonoyl chloride precursors of active nitrile imine species and a base. The other part is used to generate acetylene from CaC2 and water. Partitioning of the reactants improves the yields of desired pyrazoles up to 99% and simplifies their isolation to a simple procedure of solvent evaporation. The approach requires no complex equipment and utilizes inexpensive, safe, and easy to handle calcium carbide as a starting material. A model deuterium incorporation is carried out according to the developed methodology, producing a series of novel 4,5-dideuteropyrazoles with excellent deuterium enrichment. Theoretical calculations on reaction mechanism and characterization of possible intermediate structures were performed.
Copper(ii)-catalyzed coupling reaction: An efficient and regioselective approach to N′,N′-diaryl acylhydrazines
Zhang, Ji-Quan,Huang, Gong-Bin,Weng, Jiang,Lu, Gui,Chan, Albert S. C.
supporting information, p. 2055 - 2063 (2015/03/05)
Using N′-aryl acylhydrazines as aryl donors, a novel copper(ii)-catalyzed homo-coupling reaction of N′-aryl acylhydrazines has been developed for the synthesis of N′,N′-diaryl acylhydrazines. We also provided a complementary procedure for the preparation of unsymmetrical diaryl acylhydrazines via cross-coupling reaction. These protocols featured mild reaction conditions, wide functional group tolerance and highly regioselective products. Control experiments indicated that this kind of coupling reaction might undergo a transient acyl diazene intermediate. This journal is
Synthesis of N-aryl hydrazides by copper-catalyzed coupling of hydrazides with aryl iodides.
Wolter,Klapars,Buchwald
, p. 3803 - 3805 (2007/10/03)
[reaction--see text] A convenient method for intermolecular N-arylation of hydrazides with substituted aryl iodides in the presence of a copper catalyst and Cs(2)CO(3) is reported. The C-N coupling of N-Boc hydrazine with para- and meta-substituted aryl iodides afforded the N-arylated products A, regioselectively. A reversal in regioselectivity is observed for the arylation of benzoic hydrazide with ortho-substituted aryl iodides, providing the N'-arylated products B.
Non Conventional Syntheses of Heterocyclic Compounds. 3. Synthesis of Indazole Derivatives
Fusco, Raffaello,Marchesini, Alessandro,Sannicolo, Franco
, p. 773 - 778 (2007/10/02)
The thermal cyclization of a few 2,6-dimethylphenylazo compounds to indazole derivatives is described.
Method of use, composition, and compounds
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, (2008/06/13)
Certain benzoyl chloride phenylhydrazones have been found to be active against insects and mites. The benzoyl ring and the phenylhydrazone ring can be substituted with a halogen atom, a nitro group, or an alkyl group of from 1 to 6 carbon atoms, inclusive
