A reliable method for encapsulation of palladium nanoparticles (6−8 nm particles) in halloysite (Pd@Hal) has been developed. The Pd@Hal was found to be a highly efficient room-temperature catalyst for Suzuki− Miyaura cross-coupling reactions that gave high yields of a diverse array of coupling products in 5:2 n-PrOH/H 2 O within 1 h. The catalytic system was remarkably effective with a broad substrate scope. In addition, the catalyst was easily recovered and recycled without a significant loss of catalytic activity.
Halloysite,
a natural clay with a hollow tubular structure, was
studied as a catalyst for the esterification of biomass-derived carboxylic
acids (levulinic acid, fumaric acid, maleic acid, and succinic acid)
with four different alcohols (MeOH, EtOH, n-PrOH,
and n-BuOH). Reaction conditions were optimized (10
mol % halloysite, 170 °C, 24 h) and gave high yields of the corresponding
esters and diesters (>90%). The halloysite was easily recovered
and
recycled after washing and drying.
A reliable method for encapsulation of iridium nanoparticles (6− 8 nm particles) in halloysite Ir@Hal has been developed. The Ir@Hal nanocomposite was found to be a highly efficient catalyst for the hydrogenation and transfer hydrogenation of the carbonyl group of aryl aldehydes, aryl ketones, and aliphatic ketones to afford alcohols in high yields. In addition, phenol could be hydrogenated to furnish cyclohexanol (93−95% yield) at ambient pressure at 50 °C. Further, the catalyst was easily recovered and recycled without significant loss of catalytic activity over multiple trials.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.