Synthesis of 4-azafluorenes substituted at the position 9 based on 9,9-diphenacyl(phenacylidene)-4-azafluorene

Functionally substituted 4-azafluorenes were synthesized by the modification of the carbonyl groups of 9,9-diphenacyl-4-azafluorene. The usual reductive cleavage of 9,9-di(α-bromophenacyl)-4-azafluorene by hydrazine, leading to the formation of diphenylpyridazine, was found. A method for the oxidation of methiodides of 9-substituted 4-azafluorenes to the corresponding indenopyridones was developed. © 1994 Plenum Publishing Corporation.