18793-81-2Relevant academic research and scientific papers
Pd-Catalyzed Coupling of Thioamides with N-Tosylhydrazones/Trapping by Esters Cascade Reaction
Cai, Zhongliang,Yao, Zhi,Jiang, Liqin
supporting information, p. 311 - 316 (2021/01/26)
N,N-Disubstituted thioamides coupled with N-tosylhydrazones under Pd(TFA)2/tBuXPhos catalyst and NaOtBu, and the intermediates from palladium carbene migratory insertion containing β-hydrogen were trapped by intramolecular esters activated by BF3·Et2O ins
Blue light-promoted cyclopropenizations of N-tosylhydrazones in water
Yan, Kaichuan,He, Hua,Li, Jianglian,Luo, Yi,Lai, Ruizhi,Guo, Li,Wu, Yong
supporting information, p. 3984 - 3987 (2021/06/15)
Carbene transfer reactions play an important role in the field of organic synthesis because of their ability to construct a variety of molecules. Herein, we reported on blue light-induced cyclopropenizations of N-tosylhydrazones in water, which avoids the use of expensive metal-based catalysts and toxic organic solvents. This metal-free and operationally simple methodology enable highly efficient cyclopropenizations, X-H insertion reactions, and cyclopropanation under mild reaction conditions.
Stoichiometric Photochemical Carbene Transfer by Bamford–Stevens Reaction
Aseeva, Polina,Empel, Claire,Jana, Sripati,Koenigs, Rene M.,Li, Fang,Verspeek, Dennis
supporting information, p. 2586 - 2591 (2020/03/04)
The photolysis of diazoalkanes is a timely strategy to conduct carbene-transfer reactions under mild and metal-free reaction conditions, and has developed as an important alternative to conventional metal-catalyzed carbene-transfer reactions. One of the major limitations lies within the rapidly occurring side reaction of the carbene intermediate with remaining diazoalkane molecules that result in the use of an excess of the reaction partner and thus impacts on the reaction efficiency. Herein, we describe a protocol that takes advantage of the in situ generation of donor–acceptor diazoalkanes by Bamford–Stevens reaction. Following this strategy, the concentration of the diazoalkane reaction partner can be minimized to reduce unwanted side reactions and to now conduct photochemical carbene transfer reactions under stoichiometric reaction conditions. We have explored this approach in the C?H and N?H functionalization and cyclopropanation reaction of N-heterocycles and could demonstrate the applicability of this method in 51 examples.
Synthesis of 3-substituted indazoles from arynes and N-tosylhydrazones
Li, Pan,Zhao, Jingjing,Wu, Chunrui,Larock, Richard C.,Shi, Feng
supporting information; experimental part, p. 3340 - 3343 (2011/09/12)
Readily available, stable, and inexpensive N-tosylhydrazones react with arynes under mild reaction conditions to afford 3-substituted indazoles in moderate to good yields. The reaction appears to involve a dipolar cycloaddition of in situ generated diazo
