Solvent-Dependent Diastereoselectivities in Reductions of β-Hydroxyketones by SmI2

Abstract
The reductions of a series of β-hydroxyketones by SmI2 were examined in THF, DME, and CH3CN using methanol as a proton source. Reductions in THF and DME typically lead to the syn diastereomer with DME providing higher diastereoselectivities. Reductions in CH3CN provided the anti diastereomer predominantly. This study reveals that solvation plays an important role in substrate reduction by SmI2.