7497-13-4Relevant articles and documents
[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)
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.
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
