886193-32-4Relevant academic research and scientific papers
Sunlight-promoted Direct Irradiation of N-centred Anion: The Photocatalyst-free Synthesis of Pyrazoles in Water
Zhang, Te,Meng, Yunge,Lu, Jinye,Yang, Yuting,Li, Gong-Qiang,Zhu, Chunyin
supporting information, p. 3063 - 3068 (2017/12/04)
A practical method through sunlight mediated annulation of α,β-unsaturated hydrazones has been developed for the synthesis of pyrazole. Based on the analysis of UV-Vis absorption of the substrate, the reaction was designed to avoid the use of external photocatalysis and proceeds via direct irradiation of N-centred anion by sunlight. The key features of this reaction include operational simplicity, readily available reagents, and amenability to gram-scale synthesis. (Figure presented.).
Sulphur promoted C(sp3)-C(sp2) cross dehydrogenative cyclisation of acetophenone hydrazones with aldehydes: Efficient synthesis of 3,4,5-trisubstituted 1H-pyrazoles
Vanjari, Rajeshwer,Guntreddi, Tirumaleswararao,Kumar, Saurabh,Singh, Krishna Nand
, p. 366 - 369 (2015/01/09)
A novel strategy for the cross dehydrogenative coupling (CDC) of acetophenone hydrazones and aldehydes has been developed for the synthesis of highly substituted pyrazoles. This work, for the first time, uses elemental sulfur as a promoter as well as a hydrogen acceptor in effecting the Csp3-Csp2 bond formation via C-H activation. This journal is
An efficient one-pot synthesis of 3,5-disubstituted 1H-pyrazoles
Wu, Lei-Lei,Ge, Yi-Cen,He, Ting,Zhang, Lei,Fu, Xing-Li,Fu, Hai-Yan,Chen, Hua,Li, Rui-Xiang
, p. 1577 - 1583 (2012/06/29)
An efficient, general, one-pot, three-component procedure for the preparation of 3,5-disubstituted 1H-pyrazoles via condensation of substituted aromatic aldehydes, tosylhydrazine and terminal alkynes in toluene is reported. The reaction tolerates a variety of functional groups and sterically hindered substrates to afford the desired pyrazoles in yields of 67-91%.
