Desymmetrization of a meso-allylic acetal by enantioselective conjugate elimination.
An unprecedented enantioselective deprotonation/conjugate elimination sequence, which transforms an allylic meso-dioxepane into a chiral diene, is described. The best desymmetrization conditions (ee up to 70%) involve s-BuLi and sparteine at -78 degrees C in THF.
Xu
Ling
L
Laboratoire des Fonctions Azotées et Oxygénées Complexes de l'IRCOF, UMR CNRS 6014, Université et INSA de Rouen, 76821 Mont Saint-Aignan Cedex, France.
Regnier
Thomas
T
Lemiègre
Loïc
L
Cardinael
Pascal
P
Combret
Jean-Claude
JC
Bouillon
Jean-Philippe
JP
Blanchet
Jérome
J
Rouden
Jacques
J
Harrison-Marchand
Anne
A
Maddaluno
Jacques
J