Asymmetric tandem wittig rearrangement/Aldol reactions.
A new method for the asymmetric synthesis of alpha-alkyl-alpha,beta-dihydroxy esters that involves tandem Wittig rearrangement/aldol reactions of O-benzyl- or O-allylglycolate esters derived from 2-phenylcyclohexanol is described. This sequence constructs two C-C bonds and two stereocenters, one of which is quaternary, to afford syn diol products with excellent stereocontrol. Cleavage of the chiral auxiliary affords enantiomerically enriched products with up to 95% ee. The application of this method to the preparation of a key intermediate in the synthesis of the antifungal agent alternaric acid is also described.
Giampietro
Natalie C
NC
Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109-1055, USA.
Kampf
Jeff W
JW
Wolfe
John P
JP
D000447:Aldehydes / Q000737:chemistry*; D004952:Esters / Q000737:chemistry; D013237:Stereoisomerism; D013379:Substrate Specificity
D000447:Aldehydes; D004952:Esters; C116609:3-hydroxybutanal