42166-50-7Relevant articles and documents
Cross-Coupling between Hydrazine and Aryl Halides with Hydroxide Base at Low Loadings of Palladium by Rate-Determining Deprotonation of Bound Hydrazine
Borate, Kailaskumar,Choi, Kyoungmin,Goetz, Roland,Hartwig, John F.,Shinde, Harish,Wang, Justin Y.,Zuend, Stephan J.
supporting information, p. 399 - 408 (2020/10/29)
Reported here is the Pd-catalyzed C–N coupling of hydrazine with (hetero)aryl chlorides and bromides to form aryl hydrazines with catalyst loadings as low as 100 ppm of Pd and KOH as base. Mechanistic studies revealed two catalyst resting states: an arylpalladium(II) hydroxide and arylpalladium(II) chloride. These compounds are present in two interconnected catalytic cycles and react with hydrazine and base or hydrazine alone to give the product. The selectivity of the hydroxide complex with hydrazine to form aryl over diaryl hydrazine was lower than that of the chloride complex, as well as the catalytic reaction. In contrast, the selectivity of the chloride complex closely matched that of the catalytic reaction, indicating that the aryl hydrazine is derived from this complex. Kinetic studies showed that the coupling process occurs by rate-limiting deprotonation of a hydrazine-bound arylpalladium(II) chloride complex to give an arylpalladium(II) hydrazido complex.
PROCESS FOR THE SYNTHESIS OF ARYL HYDRAZINES
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Page/Page column 22; 24, (2020/06/01)
The invention relates to a process for the synthesis of aryl hydrazinesof formula I or a salt thereof, which process comprises subjecting an arene of formula II to a coupling reaction with hydrazine or a derivative thereof, wherein the coupling reaction is conducted in the presence of a catalyst comprising palladium and a diphosphine ligand, wherein the phosphorus atoms are connected through two, three, four, or five atoms selected from car- bon, nitrogen, oxygen or iron, and in which the non-connecting phosphorus substituents are C1- C 10-alkyl or C3-C10-cycloalkyl, wherein the amount of Pd used is up to 0.5 mol-% relative to the amount of arene of formula II; and a base.
Efficient synthesis of aryl hydrazines using copper-catalyzed cross-coupling of aryl halides with hydrazine in PEG-400
Chen, Junmin,Zhang, Yimin,Hao, Wenyan,Zhang, Rongli,Yi, Fei
, p. 613 - 617 (2013/07/25)
An efficient and convenient method for the synthesis of aryl hydrazines is described via copper-catalyzed cross-coupling of aryl halides with aqueous hydrazine in PEG-400. This protocol is applicable to both electron-deficient and electron-rich aryl iodides and bromides, and even to sterically hindered substrates, giving aryl hydrazines in good to excellent yields.