Mizoroki–Heck Reaction of Aryl Halides and Dialkyl Allylphosphonates in Water Catalyzed by Reusable Palladium Nanoparticles

Abstract Commercial [PdCl 2 (NH 3 ) 2 ] was applied to catalyze the Mizoroki–Heck coupling of aryl halides with dialkyl allylphosphonates using i Pr 2 NH as the base in water under aerobic conditions. The reaction was conducted at 80 °C (for aryl iodides) or 120 °C (for aryl bromides) for 36 h, giving the corresponding aryl‐substituted allylphosphonates in good to excellent yields, and both water‐soluble and insoluble aryl halides could be utilized in this reaction. After extracting the reaction solution with ethyl acetate, the residual aqueous solution was reused for the same reaction several times, and the true catalyst was found to be palladium nanoparticles. In addition, a one‐pot synthesis of 1,4‐diarylbuta‐1,3‐dienes, which combined this catalytic reaction with the Horner–Wadsworth–Emmons–Wittig reaction, was also performed.