OXIDATIVE COUPLING IN 4a,9-DIAZA-1,2,4a,9a-TETRAHYDROFLUORENE DERIVATIVES. 2. SYNTHESIS OF METHYLENEQUINONEIMINES

Article abstract of DOI:10.1007/BF00756416

The oxidative coupling of 4a,9-diaza-1,2,4a,9a-tetrahydro-9H-fluorene derivatives with methylene-active compounds in the presence of MnO2 leads to substituted (at the methylene group) 6-methylene-4a,9-diaza-1,2,4a,9a-tetrahydro-6H-fluorene derivatives.The corresponding 2,2-disubstituted 5-dicyanomethylene-3,5-dihydrobenzimidazoles were obtained in the reaction of 2,2-disubstituted benzimidazolines with malonitrile in the presence of MnO2.