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Heterogeneous Rh and Rh/Ag bimetallic nanoparticle catalysts immobilized on chiral polymers.

ABSTRACT: The development of heterogeneous chiral catalysts has lagged far behind that of homogeneous chiral catalysts in spite of their advantages, such as environmental friendliness for a sustainable society. We describe herein novel heterogeneous chiral Rh and Rh/Ag bimetallic nanoparticle catalysts consisting of polystyrene-based polymers with chiral diene moieties. The catalysts enable high-to-excellent yields and enantioselectivities to be obtained in asymmetric 1,4-addition reactions of arylboronic acids with α,β-unsaturated carbonyl compounds such as ketones, esters, and amides, and in other asymmetric reactions. The catalysts could be readily recovered by simple filtration and reused; they could also be applied to continuous-flow synthesis. We also discuss the nature of possible reaction species based on XPS analysis.

SUBMITTER: Min H

PROVIDER: S-EPMC6761866 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature

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Heterogeneous Rh and Rh/Ag bimetallic nanoparticle catalysts immobilized on chiral polymers.

Min Hyemin H Miyamura Hiroyuki H Yasukawa Tomohiro T Kobayashi Shū S

Chemical science 20190627 32

The development of heterogeneous chiral catalysts has lagged far behind that of homogeneous chiral catalysts in spite of their advantages, such as environmental friendliness for a sustainable society. We describe herein novel heterogeneous chiral Rh and Rh/Ag bimetallic nanoparticle catalysts consisting of polystyrene-based polymers with chiral diene moieties. The catalysts enable high-to-excellent yields and enantioselectivities to be obtained in asymmetric 1,4-addition reactions of arylboronic ...[more]

PMID: 31588313

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