The goal of this PhD was to explore a new synthetic protocol for the synthesis, resolution and late stage functionalization of cationic [6]helicenes. The replacement of oxygen by nitrogen atom at bridge position is favorable due to the better charge stabilization brought by the electron-donating groups. The transformation from dioxa into azaoxa and diaza [6]helicenes is achieved in milder conditions. The enantiomers of the cationic [6]helicenes were separated using CSP-HPLC conditions in neutral or cationic derivatives and their chiroptical properties and racemization barriers were studied. In addition, an oxidative coupling between the more electrophilic dioxa [6]helicene and indoles or indoline was achieved on the naphthyl rings. This regioselective functionalization led to donor-acceptor dyes with interesting optical properties. Further tuning of the electronic properties was achieved through the addition of electron-donating or electron-withdrawing substituents at the periphery of diaza [6]helicene. Highly efficient luminophores or far-red absorbers are now accessible.