α-Chloro-β,γ-ethylenic esters: enantiocontrolled synthesis and substitutions

Douglas T Genna; Christopher P Hencken; Maxime A Siegler; Gary H Posner

doi:10.1021/ol102142a

α-Chloro-β,γ-ethylenic esters: enantiocontrolled synthesis and substitutions

Org Lett. 2010 Oct 15;12(20):4694-7. doi: 10.1021/ol102142a.

Authors

Douglas T Genna¹, Christopher P Hencken, Maxime A Siegler, Gary H Posner

Affiliation

¹ Department of Chemistry, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.

PMID: 20853879
DOI: 10.1021/ol102142a

Abstract

Chiral nonracemic γ-seleno-α,β-ethylenic esters, when treated with sulfuryl chloride and ethyl vinyl ether in hexanes, produced α-chloro-β,γ-ethylenic esters in 65-75% yields, with ee values of 95-97%, and with 1,3-syn transfer of chirality. Reaction of these allylic chloride electrophiles with methylcuprate and with sodium azide nucleophiles afforded exclusively γ-substituted-α,β-ethylenic esters with faithful anti-transfer of chirality on multigram scale.