Synthesis of fluorescent dibenzopyranones by the Diels-Alder reaction of 4-styrylcoumarins and N-phenylmaleimide and in situ aromatization using DDQ
作者:Kailas K. Sanap、Shriniwas D. Samant
DOI:10.3998/ark.5550190.0014.309
日期:——
Reaction of 7-substituted-4-styrylcoumarins and N-phenylmaleimide in nitrobenzene under reflux conditions affords mainly 7-substituted-2,11-diphenyl-3a,10,11,11a-tetrahydro(1)- benzopyrano(3,4-e)isoindole-1,3,4(2 H)-triones. The same reaction in o-dichlorobenzene in the presence of DDQ gives the corresponding aromatizeddibenzopyranones. The dibenzopyranones are fluorescent and their UV and fluorescence