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Evaluation of a chiral cubane-based Schiff base ligand in asymmetric catalysis reactions.

ABSTRACT: Recently, a novel chiral cubane-based Schiff base ligand was reported to yield modest enantioselectivity in the Henry reaction. To further explore the utility of this ligand in other asymmetric organic transformations, we evaluated its stereoselectivity in cyclopropanation and Michael addition reactions. Although there was no increase in stereocontrol, upon computational evaluation using both M06L and B3LYP calculations, it was revealed that a pseudo six-membered ring exists, through H-bonding of a cubyl hydrogen to the copper core. This decreases the steric bulk above the copper center and limits the asymmetric control with this ligand.

SUBMITTER: Biegasiewicz KF

PROVIDER: S-EPMC3511016 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Evaluation of a chiral cubane-based Schiff base ligand in asymmetric catalysis reactions.

Biegasiewicz Kyle F KF Ingalsbe Michelle L ML St Denis Jeffrey D JD Gleason James L JL Ho Junming J Coote Michelle L ML Savage G Paul GP Priefer Ronny R

Beilstein journal of organic chemistry 20121022

Recently, a novel chiral cubane-based Schiff base ligand was reported to yield modest enantioselectivity in the Henry reaction. To further explore the utility of this ligand in other asymmetric organic transformations, we evaluated its stereoselectivity in cyclopropanation and Michael addition reactions. Although there was no increase in stereocontrol, upon computational evaluation using both M06L and B3LYP calculations, it was revealed that a pseudo six-membered ring exists, through H-bonding o ...[more]

PMID: 23209516

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