18793-81-2Relevant articles and documents
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
Stoichiometric Photochemical Carbene Transfer by Bamford–Stevens Reaction
Aseeva, Polina,Empel, Claire,Jana, Sripati,Koenigs, Rene M.,Li, Fang,Verspeek, Dennis
, 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.
