. . . . . . . . . . "A new generation of 2,5-dimethylthiolanes with a lockedconformation was developed to promote the asymmetricaddition of chiral sulfonium ylides to aldehydes. The novelchiral sulfur derivative 4 succeeded the synthesis of trans-stilbene oxide derivatives with enantiomeric ratios rangingfrom 95:5 to 98:2. This user-friendly organocatalytic processproved to be efficient with 20\u221210% of sulfide 4 in 1 or 2 daysof reaction. An insight into the ylide intermediate conformation is given on the basis of a computational ab initio study." . . . "Design of Sulfides with a LockedConformation as Promoters of Catalyticand Asymmetric Sulfonium YlideEpoxidation" . . . . .