5-dihydro-1,2λ6,3-oxathiazole 2-oxides 5 and 6 or their enantiomers, a number of enantiopure acyclic and cyclic 2-alkenyl sulfoximines have been prepared. After deprotonation with n-BuLi and transmetalation with chlorotris(isopropoxy)titanium chloride, these sulfoximines can be γ-hydroxyalkylated to the corresponding γ-hydroxy vinyl sulfoximines with high diastereomeric excesses (≥95% de) irrespective