A variable temperature NMR study shows that a protective group on the hydroxy function of a chiral allylic alcohol can either enhance or counter the influence of the vinyl substituent on the groundstate (GS) conformations. If the allylic hydroxy is protected as a methyl ether, the CH-eclipsed form I becomes favored to a greater degree for normal chiral alkenes. Furthermore, conformer I becomes preferred even for the y-hydroxy-a, &unsaturated ...
