β-Hydroxy sulfoxides were obtained in one-pot synthesis by the ring opening of oxiranes with thiols in hexafluoroisopropanol (HFIP) without any catalyst, followed by in situ oxidation under neutral conditions. The reaction is anti-selective. β-Hydroxy sulfoxides were transformed by pyrolysis in the corresponding allylic alcohols.
Stereoselective hydride reductions of chiral 2-p-tolylsulfinylcycloalkanones
作者:Ana B. Bueno、M. Carmen Carreño、Jose L. García Ruano、Begoña Peña、Almudena Rubio、Miguel A. Hoyos
DOI:10.1016/s0040-4020(01)85512-5
日期:——
The highly stereoselective hydride reductions of chiral 2-p-tolylsulfinyl-cyclopentanones and cycloheptanones are described. With DIBAL (electrophilic hydride) the configuration induced at C-1 is controlled by the sulfinyl group (1,3-asymmetric induction), and it can be inverted by using ZnCl2 as catalyst. With L-selectride the stereoselectivity is directed by the C-2 chiral groups (1,2-asymmetric induction). Other nucleophilic hydrides gave results which depend on the reagents and the size of the rings.