N-allylation and N-benzylation of 2-phenylindole and its condensation with carbonyl compounds

By allylation and benzylation of 2-phenyl- and 2-phenyl-3-formylindole, N-allyl- and benzyl-substituted indoles have been obtained. By condensation of 2-phenylindole with 2-formylfluorene, and also with 4-aza- or 3-methyl-2-azafluorenone, compounds containing fragments of the indole, fluorene, and azafluorenone systems have been synthesized. In the interaction of 2-phenylindole or indole with formaldehyde and 2,5-dimethylpiperidin-4-one, depending on the temperature, bis(2-phenylindol-3-yl)methane, (2′,5′-dimethyl-4′-oxopiperidino)-(1-indolyl)methane, and bis(indol-3-yl)methane are formed. © 1993 Plenum Publishing Corporation.