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Ligand scaffold optimization of a supramolecular hydrogenation catalyst: Analyzing the influence of key structural subunits on reactivity and selectivity.

ABSTRACT: Results are reported for the catalytic asymmetric hydrogenation of two prototypical substrates with a series of more than 150 closely related supramolecular catalysts differing in only their ligand/catalyst scaffold. These modular catalysts are constructed from four subunits and vary widely in their reactivity (no reaction to quantitative yield) and enantioselectivity (racemic to 96% ee). Analysis of the ligand/catalyst scaffold optimization data reveals how each subunit contributes to the effectiveness of the modular supramolecular catalyst. The results suggest that a balance between key elements of rigidity and flexibility is required for the successful catalysts and, moreover, that this balance is required to enable effective fine-tuning via catalyst scaffold optimization.

SUBMITTER: Thacker NC

PROVIDER: S-EPMC3601680 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Ligand scaffold optimization of a supramolecular hydrogenation catalyst: Analyzing the influence of key structural subunits on reactivity and selectivity.

Thacker Nathan C NC Moteki Shin A SA Takacs James M JM

ACS catalysis 20121105 12

Results are reported for the catalytic asymmetric hydrogenation of two prototypical substrates with a series of more than 150 closely related supramolecular catalysts differing in only their ligand/catalyst scaffold. These modular catalysts are constructed from four subunits and vary widely in their reactivity (no reaction to quantitative yield) and enantioselectivity (racemic to 96% ee). Analysis of the ligand/catalyst scaffold optimization data reveals how each subunit contributes to the effec ...[more]

PMID: 23525350

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