【文章名】SYNTHESIS OF A NOVEL NON-BENZENOID QUINONE, 3,10-DIHYDRO-2,4-DIMETHYL-7,13-METHANOCYCLOHEPTA[11]-AN NULENE-3,10-DIONE, FROM 8H-7,9-BIS(METHOXYCARBONYL)-5,11-METHANO[11]ANNULENO[c]FURAN-8-ONE
SYNTHESIS OF A NOVEL NON-BENZENOID QUINONE, 3,10-DIHYDRO-2,4-DIMETHYL-7,13-METHANOCYCLOHEPTA[11]-AN NULENE-3,10-DIONE, FROM 8H-7,9-BIS(METHOXYCARBONYL)-5,11-METHANO[11]ANNULENO[c]FURAN-8-ONE
[摘要]:8H-7,9-Bis(methoxycarbonyl)-5,11-methano[11]anuleno[c]furan-8-one (3) undergoes [4+3] cycloaddition with an oxyallyl species generated from 2,4-dibromo-3-pentanone in the presence of KI and copper, followed by dehydration in fluorosulfuric acid to give cyclohepta[11]annulenedione diester 9. After hydrolysis of the ester groups, decarboxylation yielded the title quinone 6. The H-1 NMR spectrum of 6 in D2SO4 indicates generation of its protonated dicationic species.