First enantioselective synthesis of vinyl oxiranes from aldehydes and ylides generated from allyl halides and chiral sulfides.
Asymmetric allylidenation of aldehydes with sulfur ylides is possible with proper substitution of the initial sulfide, to avoid the [2,3] sigmatropic rearrangement of the unsaturated ylides. One-pot reaction of (2R,5R)-dimethylthiolane with allyl halides, aldehydes, and sodium hydroxide in tert-butyl alcohol affords vinyl oxiranes in good yields. Enantiomeric excesses up to 90% and trans selectivities have been achieved with methallyl-type halides.
Zanardi
Jacques
J
Laboratoire de Chimie Moléculaire et Thio-organique (UMR CNRS 6507), ISMRA-Université de Caen, 6 Boulevard du Maréchal Juin, F-14050 Caen, France.
Lamazure
David
D
Minière
Stéphanie
S
Reboul
Vincent
V
Metzner
Patrick
P