Addition of olefins to acetylacetone catalyzed by cooperation of Brønsted acid site of zeolite and gold cluster

HY zeolite-supported Au clusters (Au0HY) prepared by deposition–precipitation method, well characterized by XANES, EXAFS, and NH3- and acetyl acetone-adsorption IR, were tested for addition of acetyl acetone to alkenes. Au0HY showed higher selectivity to the addition product than HY zeolite-supported Au(OH)3 and Au clusters supported on NH4+-exchanged Y zeolite, Al2O3, MgO, SiO2, and TiO2. Studies on the effect of Au oxidation state, Au cluster size and Brønsted acidity of zeolite on the catalytic showed that co-presence of metallic Au with smaller cluster size and the acidic OH groups of the zeolite was necessary to the selective formation of the addition product. Cooperation mechanism of the Brønsted acid sites of the zeolite and Au clusters is proposed.

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► HY zeolite-supported Au clusters act as heterogeneous catalysts for the addition of acetyl acetone to alkenes.
► Co-presence of metallic Au with smaller cluster size and the acidic OH groups of the zeolite was found to be necessary to achieve high selectivity.
► This is a rare example for the Brønsted acid and Au cooperating catalysis in organic reactions.