Carbon-substituted Co(III) salens as effective catalysts for enantioselective Diels-Alder reactions

Synlett

Volumn , Issue 13, 2004, Pages 2440-2442

  McGilvra, Jeff D ^a   Rawal, Viresh H ^a  

^a UNIVERSITY OF CHICAGO   (United States)

Author keywords

Aminodienes; Asymmetric catalysis; Enantioselective Diels Alder; Lewis acids; Substituent effects

Indexed keywords

1,3 BUTADIENE; ALKYL GROUP; AMINE; ANTIMONY DERIVATIVE; BENZYL DERIVATIVE; CARBAMIC ACID DERIVATIVE; CARBON; COBALT DERIVATIVE; FLUORINE DERIVATIVE; POLYCYCLIC AROMATIC HYDROCARBON DERIVATIVE; SILANE DERIVATIVE;

ARTICLE; CATALYST; CYCLOADDITION; DESILYLATION; DIELS ALDER REACTION; ENANTIOSELECTIVITY; REACTION ANALYSIS; STEREOSPECIFICITY; SYNTHESIS;

EID: 8644272429     PISSN: 09365214     EISSN: None     Source Type: Journal    
DOI: 10.1055/s-2004-834799     Document Type: Article

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21. Values for the enantiomer ratio are included to distinguish subtle differences in selectivity for systems that would otherwise appear identical due to rounding of the ee values.
22. These results show that even a small amount of mono-aryl substituted salen complex (∼2%), similar to that which would be produced from partial protodesilation of the silyl salens, produces cycloadducts with significantly lower ee values. Presumably, the less encumbered complex catalyzes a faster, less enantioselective reaction.