Publication
Title
Enantioselective binding of structural epoxide isomers by a chiral vanadyl salen complex: a pulsed EPR, cw-ENDOR and DFT investigation
Author
Abstract
The mode of chiral interaction between a series of asymmetric epoxides (propylene oxide, butylene oxide, epifluorohydrin and epichlorohydrin) and a chiral vanadyl salen complex, N, N-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexane-diamino-vanadium (IV) oxide, [VO( 1)], was investigated by a range of electron magnetic resonance techniques (EPR, ENDOR, HYSCORE) and DFT. Enantiomer discrimination of the weakly bound epoxides by the vanadyl complex was evident by cw-ENDOR. The origin of this discrimination was attributed to a number of factors including H-bonds, steric properties and electrostatic contributions, which collectively control the outcome of the chiral interaction. DFT revealed the role of a key H-bond, formed between the epoxide oxygen atom (Oepoxide) and the methine proton (Hexo) attached to the asymmetric carbon atom of the chiral vanadyl salen complex, thereby providing a direct pathway for stereochemical communication between complex and substrate. These findings reveal the potential importance of weak outer sphere interactions in stereoselectivities of enantioselective homogeneous catalysis.
Language
English
Source (journal)
Physical chemistry, chemical physics / Royal Society of Chemistry [London] - Cambridge, 1999, currens
Publication
Cambridge : 2009
ISSN
1463-9076 [print]
1463-9084 [online]
Volume/pages
11:31(2009), p. 6757-6769
ISI
000268481200022
Full text (Publisher's DOI)
UAntwerpen
Faculty/Department
Research group
Publication type
Subject
Affiliation
Publications with a UAntwerp address
External links
Web of Science
Record
Identification
Creation 09.09.2009
Last edited 02.08.2017
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