Cyclocarbopalladation: 5-exo-dig cyclization versus direct Stille cross-coupling reaction. The influence of the alpha,beta-propargylic substitution.
Several bicyclic compounds bearing a 1,2-cyclopentanediol have been prepared from various anti- or syn-gamma-bromopropargylic diols and cis-dioxolanes under palladium(0) catalysis. The reaction proceeds through a 5-exo-dig cyclocarbopalladation. When the corresponding trans-dioxolanes are used, the only products isolated are obtained from a direct Stille cross-coupling reaction. [reaction: see text]
Salem
Bahaâ
B
Faculté de Pharmacie, Université Louis Pasteur de Strasbourg (UMR 7081 CNRS/ULP), 74 route du Rhin, 67401 Illkirch-Cedex, France.
Delort
Estelle
E
Klotz
Philippe
P
Suffert
Jean
J