Z/E Stereoselective synthesis of β-bromo Baylis-Hillman ketones using MgBr2 as promoter via a one-pot three-component reaction
Han-Xun Wei*, Richard L. Jasoni, Jiali Hu, Guigen Li and Paul W. Paré
*Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA, Email: hweirdg.boehringer-ingelheim.com
H.-X. Wei, R. L. Jasoni, J. Hu, G. Li, P. W. Pare, Tetrahedron, 2004, 60, 10233-10237.
A stereoselective multicomponent synthesis of (Z)-β-bromo Baylis-Hillman ketones uses MgBr2 as both the Lewis acidic promoter and the bromine source for the Michael-type addition with α,β-acetylenic ketones to form an active β-bromo allenolate intermediate, which in turn attacks various aldehydes to afford β-bromo Baylis-Hillman adducts in good yields and Z-selectivity.
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