Suzuki Coupling Reactions Catalyzed by PdO Dispersed on Dealuminated Y Zeolite in Air under Ambient Conditions

Suzuki coupling reactions are performed using PdO loaded on dealuminated Y (USY) zeolite. The reaction between bromobenzene and phenylboronic acid is complete in 15 min at room temperature in air, with a turnover number of 1300. The reaction can be repeated at least five times by using 1 wt % Pd. Inductively coupled plasma analysis does not reveal the dissolution of Pd from products, even if the reaction is repeated up to four times. Pd K‐edge extended X‐ray absorption fine structure analysis reveals the presence of molecular‐like PdO and a mixture of Pd⁰–PdO before and after the reaction, respectively. This is probably because Pd stabilized by Al sites is present at the II sites of the Y‐type zeolite, as estimated using first‐principles calculations. Conversely, Pd species change to PdO clusters after repeated reactions in air using the thermally treated sample.