Reactions of tosylhydrazones of benzaldehyde and benzophenone with cyanoalkenes in a basic two-phase system
作者:Andrzej Jończyk、Joanna Włostowska、Mieczysław Mąkosza
DOI:10.1016/s0040-4020(01)00133-8
日期:2001.4
Reaction of tosylhydrazones 1a,b with cyanoalkenes 3a,b, carried out in the presence of concentrated aq. sodium hydroxide in dioxane, afforded either cyanocyclopropanes 5, 9 or pyrazoles 13, 14 and 16, 17. The process takes place via generation of diazocompounds 2a,b from la,b their [3+2] cycloaddition to 3a,b with the formation of unstable pyrazolines 4, further fate of which depends on the structure of R-1 and R-2 substituents. (C) 2001 Elsevier Science Ltd. All rights reserved.