74618-12-5Relevant articles and documents
1,3-Dipolar Cycloaddition of Alkyne-Tethered N-Tosylhydrazones: Synthesis of Fused Polycyclic Pyrazoles
Zheng, Yang,Zhang, Xiaolu,Yao, Ruwei,Wen, Yuecheng,Huang, Jingjing,Xu, Xinfang
, p. 11072 - 11080 (2016/11/28)
A general and transition-metal-free access to the fused polycyclic pyrazoles via an intramolecular 1,3-dipolar cycloaddition reaction of alkyne-tethered tosylhydrazones has been reported. The pure solid products could be obtained without column chromatography in high to excellent yields, and the obtained products are useful bioactive molecules or could be used as the key intermediate for synthesis of these compounds in one or two steps. Additionally, a [3+2]-cycloaddition followed by a direct H-shift aromatization reaction mechanism was proposed, which is different from the previously reported aryl or alkyl sequential [1,5]-sigmatropic rearrangement pathway.
(1)BENZOPYRANO(4,3-c)PYRAZOLES BY INTRAMOLECULAR NITRILE IMINE ADDITION TO ACETYLENES
Janietz, Dietmar,Rudorf, Wolf-Dieter
, p. 1661 - 1666 (2007/10/02)
2-Alkynyloxy-benzaldehydes 1 are obtained by alkylation of the corresponding salicylaldehydes either with p-toluenesulfonic acid propargylester or 1-acetoxy-4-chloro-but-2-yne.The aldehydes 1 are converted into the hydrazones 2 by reaction with p-toluenes
