1073-69-4Relevant articles and documents
Solid-supported sulfonylhydroxylamine as an effective N-animating agent of anilines
Ohno, Hiroshi,Tanaka, Hiroshi,Takahashi, Takashi
, p. 1191 - 1194 (2005)
An effective method for the synthesis of aryl hydrazines by amination of anilines using the solid-supported phenylsulfonylhydroxylamine was described. Treatment of aniline with the solid-supported aminating agent, followed by removal of the resin, provided the corresponding hydrazine in 21% yield. The resulting hydrazines were directly adapted to the solid-phase synthesis of indoles, providing nine naltrindole derivatives varying the substituents on the aromatic rings.
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 21-23; 25; 26; 30; 31; 34; 35, (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.
Method for synthesizing 1-(2,4-dichlorophenyl)-3-methyl-4-difluoromethyl-1,2,4-triazole-5-ketone
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Paragraph 0056; 0057, (2018/03/28)
The invention discloses a method for synthesizing 1-(2,4-dichlorophenyl)-3-methyl-4-difluoromethyl-1,2,4-triazole-5-ketone. The method takes p-chloroaniline as a raw material, through diazotization, reduction, and salt forming, p-chlorophenylhydrazine hydrochloride is synthesized, p-chlorophenylhydrazine is obtained through alkali neutralization, under condition that tert-butyl alcohol is taken asa solvent, chlorophenylhydrazine, acetaldehyde, sodium cyanate and sodium hypochlorite are subjected to condensation, cyclisation and an oxidation reaction to generate 1-p-chlorophenyl-3-methyl-1H-1,2,4-triazole-5-ketone, and the 1-p-chlorophenyl-3-methyl-1H-1,2,4-triazole-5-ketone is subjected to salt forming, reaction with chlorodifluoromethane, and chlorination to obtain the 1-(2,4-dichlorophenyl)-3-methyl-4-difluoromethyl-1,2,4-triazole-5-ketone (a sulfentrazone intermediate). The synthetic method takes p-chloroanniline as the raw material, the synthetic method is realized by only one-time chlorination, steric hindrance for intermediate synthesis is small, and the impurity is low, so that the yield is increased; in addition, the raw materials required by the synthesis route are easilyacquired, the cost is low, the condition is mild, operation is simple, security is high, and the synthesis method is in favor of realizing industrial production.