Ni-Catalyzed Larock Indenone Annulation with Aliphatic- and Silyl-Substituted Alkynes Supported by Mechanistic Analysis

Phosphine-Based Porous Organic Polymer-Stabilized Palladium Nanoparticle Catalyst for the Regioselective Synthesis of Indenones

Phosphorus-embedded porous organic polymers (P-POPs) play a vital role in catalysis and sustainable chemical synthesis. This study uses an olefin-linked P-POP to stabilize Pd nanoparticles that catalyze Larock's annulation to synthesize symmetrical indenones in high yields. Unsymmetric indenones were obtained with exclusive regioselectivities by employing an intramolecular dicarbofunctionalization of a modular alkyne. The approach addresses selectivity challenges in indenone synthesis and broadens the reaction scope by incorporation of aryl halides. The catalyst is robust and recyclable.