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 Fe3+ ions, achieving a low detection limit of 30.07 × 10–9 M.
Kamaraj et al. (Mon,) studied this question.