Regio- and Diastereoselective Samarium-Mediated Allylic Benzoate Reductions

Trevor F. Stockdale; Gregory W. O’Neil

doi:10.1055/s-0036-1590831

Synlett, Table of Contents

Synlett 2017; 28(17): 2267-2271
DOI: 10.1055/s-0036-1590831

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Regio- and Diastereoselective Samarium-Mediated Allylic Benzoate Reductions

Trevor F. Stockdale

Department of Chemistry, Western Washington University, Bellingham, WA, USA Email: oneilg@wwu.edu

,

Gregory W. O’Neil*

Department of Chemistry, Western Washington University, Bellingham, WA, USA Email: oneilg@wwu.edu

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Abstract

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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

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References

References and Notes

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Supplementary Material

Supporting Information