A visible-light-driven oxidative 6π heterocycilization for the synthesis of structurally diverse π-conjugated polycyclic 1-aminoisoquinolines has been developed. The N-heterocycles exhibit suitable optical properties for the application as fluorescence quantum yield standards. DFT calculation was employed to gain insight into the mechanism and results depicted that deprotonation is the rate-determining step, which can be promoted by TFA additive.