Stereospecific Copper(II)-Catalyzed Tandem Ring Opening/Oxidative Alkylation of Donor–Acceptor Cyclopropanes with Hydrazones: Synthesis of Tetrahydropyridazines
Aerobic copper(II)-catalyzed tandem ringopening and oxidative C–H alkylation of donor–acceptorcyclopropanes with bisaryl hydrazones is accomplished to produce tetrahydropyridazines, in which copper(II) plays dual role as a Lewis acid as well as redox catalyst. The reaction is stereospecific, and optically active cyclopropanes can be reacted with high optical purities (89–98% enantiomeric excess)
novel efficient tandem reaction of hydrazones and α-bromo ketones is reported for the preparation of 1,3,5-trisubstituted pyrazoles by visible light catalysis. In this system, the monosubstituted hydrazones show wonderful reaction activity with alkyl radicals, generated from α-bromo ketones. A radical addition followed by intramolecular cyclization affords the important pyrazole skeleton in good to
Ligand-free Cu(<scp>ii</scp>)-mediated aerobic oxidations of aldehyde hydrazones leading to N,N′-diacylhydrazines and 1,3,4-oxadiazoles
作者:Lei Liu、Suliu Feng
DOI:10.1039/c7ob00042a
日期:——
A Cu(II)-mediated synthesis of N,N′-diacylhydrazines and 1,3,4-oxadiazoles from aldehyde hydrazones has been developed. This is the first time that the synthesis of N,N′-diacylhydrazines and 1,3,4-oxadiazoles using N,N-dimethylamides as the acylation reagent and O2 in air as the oxidation reagent is reported. These reactions offered several advantages including simple workups, ligand-free inexpensive
Palladium-Catalyzed Cross-Coupling of Aryl Chlorides and Tosylates with Hydrazine
作者:Rylan J. Lundgren、Mark Stradiotto
DOI:10.1002/anie.201003764
日期:2010.11.8
Hydrazine is not a problem anymore: The title transformation is the first reaction to yield aryl hydrazines through the cross‐coupling of aryl chlorides and tosylates with hydrazine. An appropriately designed palladium catalyst allows this reaction to proceed rapidly under mild conditions, and with excellent chemoselectivity (see scheme; Ad=adamantyl, Ts=4‐toluenesulfonyl).
肼不再是问题:标题转化是通过芳基氯化物和甲苯磺酸与甲苯磺酸酯的交叉偶联反应生成芳基肼的第一个反应。适当设计的钯催化剂可使该反应在温和条件下快速进行,并具有出色的化学选择性(参见方案; Ad =金刚烷基,Ts = 4-甲苯磺酰基)。
An Electrochemical Way to Generate Amphiphiles from Hydrazones for the Synthesis of 1,2,4‐Triazole Scaffold Cyclic Compounds
作者:Wangyu Li、Mingteng Xiong、Xiao Liang、Dungai Wang、Heping Zhu、Yuanjiang Pan
DOI:10.1002/open.202100268
日期:2022.1
Electrochemically forming amphiphiles, hydrazones were chosen as bifunctional reagents analogous to 1,3-dicarbonyl compounds. About 70 1,2,4-triazoles have been prepared in moderate to high yields, testifying to the validity and practicality of this strategy. This approach can also be conducted as a one-pot reaction without intermediate treatments for the construction of 1,2,4-triazoles by using phenylhydrazines