Preliminary investigations on novel camphor-derived chiral sulfones: completely stereoselective formation of tricyclic β-hydroxy sulfones from 8- and 10- functionalized camphor derivatives

Lewis, Frank, McCabe, Thomas and Grayson, David (2011) Preliminary investigations on novel camphor-derived chiral sulfones: completely stereoselective formation of tricyclic β-hydroxy sulfones from 8- and 10- functionalized camphor derivatives. Tetrahedron, 67 (39). pp. 7517-7528. ISSN 0040-4020

Full text not available from this repository. (Request a copy)
Official URL: http://dx.doi.org/10.1016/j.tet.2011.07.081

Abstract

Some camphor-derived chiral allylic and benzylic sulfones in which the sulfonyl group is located at the C-10, C-9 or C-8 methyl groups of (+)-camphor were synthesized. The C-9 and C-8 substituted sulfones were obtained via Wagner-Meerwein rearrangements of the bicyclic camphor framework. On treatment with LDA, the C-10 and C-8 substituted sulfones cyclized with complete stereoselectivity, affording tricyclic β-hydroxysulfones whose relative configurations were determined by X-ray crystallography. Tricyclic sulfones 23 and 24 underwent both β-elimination and retro-aldol reactions on further exposure to base. Reduction of the carbonyl group of the C-10 substituted sulfones afforded exo-configured isobornyl sulfones with high stereoselectivity. Reaction of the lithiated isobornyl benzylsulfone 32 with benzaldehyde generated all four of the possible product diastereomers, of which three were isolated pure by chromatography. Attempted desulfonylation of these diastereomers failed to generate the desired optically active homobenzylic alcohols but the same sulfonyl carbanion trapping/desulfonylation sequence was successful in a model achiral series of compounds

Item Type: Article
Uncontrolled Keywords: Sulfones, camphor, asymmetric synthesis, chiral auxiliary, carbanion
Subjects: F100 Chemistry
Department: Faculties > Health and Life Sciences > School of Life Sciences > Applied Sciences
Depositing User: Frank Lewis
Date Deposited: 02 Jan 2013 11:03
Last Modified: 10 Aug 2015 11:40
URI: http://nrl.northumbria.ac.uk/id/eprint/10883

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year

View more statistics


Policies: NRL Policies | NRL University Deposit Policy | NRL Deposit Licence