Regio- and Diastereoselective Samarium-Mediated Allylic Benzoate Reductions

Abstract

A regio- and diastereoselective samarium(II)-mediated reduction of allylic benzoates is described. Yields for the reactions are generally high with diastereoselectivities up to 90:10 and in some cases only a single regioisomer was obtained. The stereoselectivity of the reaction is proposed to arise from chelation of a hydroxyl-stereocenter and starting alkene geometry, with protonation occurring intramolecularly by samarium-bound water.

Key words

samarium - reduction - stereoselective synthesis - regioselectivity - diastereoselectivity

• References and Notes

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