Allylhydrazines react with phenylselenenyl sulfate, produced by diphenyl diselenide and ammonium persulfate in the presence of trifluoromethanesulfonic acid, to afford phenylseleno substituted pyrazolidines. Under the reaction conditions employed, these suffer dehydrogenation and oxidative deselenenylation to eventually give pyrazole derivatives. (C) 1997 Elsevier Science Ltd.
Iron(<scp>iii</scp>) chloride-promoted cyclization of α,β-alkynic tosylhydrazones with diselenides: synthesis of 4-(arylselanyl)-1<i>H</i>-pyrazoles
作者:Hai-Feng Yao、Fang-Hui Li、Jian Li、Shun-Yi Wang、Shun-Jun Ji
DOI:10.1039/d0ob00048e
日期:——
A highly efficient iron(iii) chloride-promoted cyclization between α,β-alkynic tosylhydrazones and diselenides to form a 4-(arylselanyl)-1H-pyrazole skeleton is studied.