Selective semi-hydrogenation of internal alkynes catalyzed by Pd–CaCO3 clusters
نویسندگان
چکیده
Clusters of calcium carbonate with palladium atoms can be considered the minimum catalytic unit Lindlar catalyst, and they are here prepared in solution or supported on alumina, to catalyze selective semi-hydrogenation internal alkynes at higher rates than terminal alkynes. This uncommon reactivity trend arises from a better accessibility sterically hindered alkyne tiny cluster catalyst. • Emerging bottom-up synthesis approach, different iteration well-known catalyst is presented this work, equally functional but without undesired lead additives. The performance new (Pd-CaCO3 clusters) outperforms commercial catalysts terms activity, except for some phenolic substrates, maintains similar selectivity towards cis -alkene. generally harder-to-hydrogenate highly reactive Pd-CaCO3 clusters due nature more accessible active site. Oxygen containing groups neighboring group positively affect reaction rates. Products interest, currently manufactured surfactant fragrances industries, synthesized novel de-novo soluble solid-supported Pd-(CaCO 3 ) n (n = 2–13) their high activity compared alkynes, presented. Mechanistic studies show that reactivity, i.e. comes electrophilicity nanoparticulated which unveils advantages isolating solid Translating sites into turns around classical approach constitutes paradigmatic shift design.
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ژورنال
عنوان ژورنال: Journal of Catalysis
سال: 2022
ISSN: ['0021-9517', '1090-2694']
DOI: https://doi.org/10.1016/j.jcat.2022.02.020