Polymer‐Confined Pd Nanocatalysts: Tailoring Adsorption Geometry for Enhanced Selectivity in Sustainable Alkylphenol Synthesis via Ketone Hydrodeoxygenation

The development of sustainable synthetic routes to access valuable alkylphenols is hampered by the poor selectivity, harsh conditions, and waste associated with traditional methods. Catalytic hydrodeoxygenation (HDO) of readily available aromatic ketones offers a potentially greener alternative, but achieving high chemoselectivity under mild conditions remains challenging. Herein, a simple yet effective strategy is reported employing a polymer‐modified palladium on carbon (Pd/C) catalyst, functionalized with dimethylamine (DMA) polymer chains (Pd/C‐DMA), for the highly efficient and selective HDO of aromatic ketones. This catalyst achieves outstanding selectivity (up to 96.6%) toward alkylphenols with complete conversion under remarkably mild conditions (80 °C, 5 bar H 2 ), significantly surpassing unmodified Pd/C and representing a substantial improvement in process greenness. Mechanistic insights reveal that the DMA polymer layer creates a confined microenvironment on the catalyst surface. This confinement effect, through steric constraints and hydrogen‐bonding interactions, enforces a specific end‐on adsorption geometry for the ketone substrate, suppressing undesired side reactions like arene ring hydrogenation. The Pd/C‐DMA catalyst demonstrates broad substrate compatibility (>95% yields for diverse ketones) and facilitates the scalable synthesis of valuable intermediates, offering a robust and sustainable platform for alkylphenol production.