Gold-catalyzed stereocontrolled synthesis of 2,3-bis(acetoxy)-1,3-dienes.
Change the ligand, change the stereochemistry: 2,3-Bis(acetoxy)-1,3-dienes are obtained in a stereocontrolled manner by a novel tandem 1,2-/1,2-bis(acetoxy) rearrangement (see scheme, R(1) and R(2) are delta(+) stabilizing). Upon stabilization of the reaction intermediates, the ligand attached to gold controls the stereochemistry of the alkene in the second acetate migration, that is, N-heterocyclic carbenes (NHC) favor cis alkenes, whereas phosphine ligands selectively afford trans olefins.
Huang
Xiaogen
X
Organisch-Chemisches Institut, Universität Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland.
de Haro
Teresa
T
Nevado
Cristina
C