Stereochemical Control in the Still-Wittig Rearrangement Synthesis of Cyclohexyl (Z)-Alkene Inhibitors of Pin1
Fig 5
Determination of the stereochemistry of Still-Wittig intermediates 6.
(A) Compound (2S,5R)-14 was synthesized to rigidify intermediate (2R,5S)-6 for nOe determination. (B) Structure of (2S,5R)-14 with lettering of the protons, structure of the major conformation showing nOe interactions, the 1H NMR and 1D nOe spectra in CDCl3 (400 MHz) are shown. Irradiation of Hi shows an nOe at Hh. Irradiation of Hg shows an nOe at Hi’. (C) The stereochemistry of enantiomer (2R,5S)-14 was determined. Structure with lettering of the protons, structure of the major conformation showing nOe interactions, and a 1D nOe spectrum in CDCl3 (400 MHz) are shown. Irradiation of Hg shows an nOe at Hi’.