Pairwise semi-hydrogenation of alkyne to cis-alkene on platinum-tin intermetallic compounds
Yuchen Pei1, Minda Chen, Xiaoliang Zhong
1Department of Chemistry, Iowa State University, Ames, IA 50011, USA. whuang@iastate.edu.
Abstract:
The molecular basis for the high cis-alkene selectivity over intermetallic PtSn for alkyne semi-hydrogenation is demonstrated. Unlike the universal assumption that the bimetallic surface is saturated with atomic hydrogen, molecular hydrogen has a higher barrier for dissociative adsorption on intermetallic PtSn due to the deficiency of Pt three-fold sites. The resulting molecular behavior of adsorbed hydrogen on intermetallic PtSn nanoparticles leads to pairwise-hydrogenation of three alkynes to the corresponding cis-alkenes, satisfying both high stereoselectivity and high chemoselectivity.
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