Diastereo- and enantioselective synthesis of polyfunctional cyclic ketones with neighboring quaternary and tertiary stereogenic centers via [2,3]Wittig rearrangement

Article abstract of DOI:10.1055/s-1996-4412

The diastereo- and enantioselective synthesis of β-substituted γ,δ-unsaturated cyclic α-hydroxy ketones 4 with neighboring quarternary and tertiary stereogenic centers via asymmetric [2,3]-Wittig rearrangement of SAEP-hydrazones 2 with good overall yields (58-74%), high anti-selectivities (92-94%) and excellent enantiomeric excesses (ee ≤ 96%) is described. The absolute configuration is determined by X-ray structure analysis of the hydrazone 3b and by ¹H NMR NOE measurements.