Intermetallic PdxIny/Al2O3 catalysts with isolated single-atom Pd sites for one-pot hydrogenation of diphenylacetylene into trans-stilbene

Novel one-pot synthesis of trans-stilbene comprises hydrogenation of diphenylacetylene into cis-stilbene followed by its hydroisomerization, over the catalyst being intermetallic Pd_xIn_y/Al₂O₃ system with isolated single-atom Pd₁ sites. The hydroisomerization rate in the process is comparable or exceeds the over-hydrogenation into 1,2-diphenylethane thus providing 76% yield of trans-stilbene in the case of Pd₂In₃/Al₂O₃ catalyst. This result presumably stems from the formation of ordered single-atom Pd₁ sites with favorable hydroisomerization ability on the surface of Pd_xIn_y catalysts.