Abstract
The development of sustainable routes for metallic nanocatalysts remains challenging due to the reliance on toxic reagents and harsh synthesis conditions. To address this, a green and efficient method was established for the preparation of palladium nanoparticles (PdNPs@Fu) using fucoidan, a naturally occurring polysaccharide with several hydroxyl and sulfate groups as a stabilizing and reducing agent. Fucoidan can rapidly reduce Pd(2+) to Pd(0) in aqueous medium under microwave irradiation (450 W, 10 min). The resulting PdNPs@Fu exhibited uniform crystalline nanoparticles (sizes ranging from 2-6 nm and an average diameter of 3.83 ± 0.09 nm), with long-term colloidal stability over 30 days. Catalytic studies demonstrated remarkable activity in model organic transformations: the Heck coupling (93% yield, 84% after five cycles) and the selective semi-hydrogenation of alkynes to (Z)-alkenes (94% yield, 85% retained activity). Notably, the catalyst afforded an overall yield of 78% in the synthesis of the sweet potato weevil (Cylas formicarius) pheromone. This research introduces a green synthesis strategy of PdNPs, integrating nanotechnology with efficient pheromone synthesis for insect control.