Synthesis and thermal transformations of pyrazolines obtained by 1,3-dipolar addition of diazocyclopropane to maleimides
作者:I. V. Kostyuchenko、E. V. Shulishov、R. R. Rafikov、Yu. V. Tomilov
DOI:10.1007/s11172-008-0226-1
日期:2008.8
complete dediazoniation at 175 °C for 10–16 h with the formation of spiro[3-azabicyclo[3.1.0]hexane-6,1′-cyclopropane]-2,4-diones 3 (80–89%) and isomeric 3-cyclopropyl-1H-pyrrole-2,5-diones 4. On the example of 3-cyclopropyl-1-phenyl-1H-pyrrole-2,5-dione, it was shown that compounds 4 are able again to enter into 1,3-dipolar cycloaddition with diazomethane or diazocyclopropane with the reaction in the case