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Polyhydroxylated indolizidine alkaloids, such as castanospermine (Ⅰ) and swainsonine (H)are of longstanding interest due to their powerful glycosidase inhibitory activity. Asymmetric hydroxyatkylation via α-amido carbanions to form C-C bands would provide a convenient approach to these compounds.In continuation of our efforts in developing asyrmmetric o-amido-hydroxyalkylation method,1 we report a new SmI2 mediated flexible asymmetric α-amido-hydroxyalkylation method. Starting from the known (S)-3-hydroxy-2-pyrrolidinone 1,2 sulfide 2 and 3 were prepared. SmI2-mediated reductive metallation of these sulfides followed by reaction with ketones or aldehydes under Barbier conditions provided C2 hydroxyalkylated products 4 in yields ranged from 30% to 83%. High C2/C3 trans diastereoselectivity and mediocre diastereoselectivity at newly formed carbinolic center have been observed. The present method will open an avenue for the asymmetric synthesis of polyhydroxylated indolizidine alkaloids.