Formation of (1S,2S,5R,6S)-(+)-6-carbanilino-1,5- dimethyltricyclo[3.2.0.0]heptane from (1R,4S)-(+)-3,8,8-tribromocamphor via a facile intramolecular cyclization-Favorskii rearrangement process
Synthesis and structure determination of 8- and 9-iodocamphorquinone bis(ethylene ketal)
The structures of 8- and 9-iodocamphorquinone bis(ethylene ketal) have been confirmed by spectroscopic and single crystal X-ray analysis. The unexpected formation of the latter isomer is attributed to intramolecular rearrangement of the camphor skeleton, the mechanistic details of which have been explored using coset analysis.
Magqi, Nceba,Lobb, Kevin A.,Kaye, Perry T.,Caira, Mino R.
Formation of 3,3,4-trimethyl-1,7-dibromonorbornane-2-one: A spectroscopic and computational study
The structure and origin of the major by-product in the synthesis of 8-bromocamphor from (+)-3,3,8-tribromocamphor has been confirmed using NMR, coset and single crystal X-ray analysis and DFT-level computational techniques.
Kaye, Perry T.,Sabbagh, Ingrid T.
p. 30 - 34
(2020/09/17)
Preliminary investigations on novel camphor-derived chiral sulfones: Completely stereoselective formation of tricyclic β-hydroxy sulfones from 8- and 10-functionalized camphor derivatives
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-hydroxy sulfones 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 benzyl sulfone 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.
Lewis, Frank W.,McCabe, Thomas C.,Grayson, David H.
supporting information; experimental part
p. 7517 - 7528
(2011/10/12)
Enanthiospecific synthesis of longiborneol and longifolene
A trimethylsilyl enol ether (34) derived from camphor (1) undergoes intramolecular Mukaiyama reaction to provide a tricyclic ketone (36) that can serve as a key intermediate in a new enantiospecific synthesis of longiborneol (11) and longifolene (12).
Kuo, David L.,Money, Thomas
p. 1794 - 1804
(2007/10/02)
Synthesis of 8,10-and 9,10-disubstituted camphor derivatives
Regiospecific bromination and debromination reactions have been used to provide a synthetic route from camphor to optically active 8,10- and 9,10-disubstituted camphor derivatives.
Dadson, William M.,Lam, Mayda,Money, Thomas,Piper, Susan E.