Abstract
A Pd(II)-catalyzed cascade C–H activation/O-annulation strategy is developed for the efficient synthesis of succinimide-integrated tetracyclic pyranonaphthoquinones using 3-aryl-2-hydroxy naphthoquinones with maleimides or itaconimides as substrates. This methodology provides a fast and efficient approach to prepare diverse tetracyclic pyranonaphthoquinones featuring spirosuccinimides or succinimide motifs via [5 + 1] cycloaddition. Notably, one of the synthesized compounds exhibited high sensitivity and selectivity as a fluorescent chemosensor for Fe(3+) ions, achieving a low detection limit of 30.07 × 10(–9) M.