A Stereoselective Approach to 2,6-Disubstituted Tetrahydropyrans by Conjugate Addition Reactions of Vinyl Sulfones
作者:D. Craig、G. Edwards、C. Muldoon
DOI:10.1055/s-1997-1016
日期:1997.11
A highly stereoselective synthesis of cis-2,6-disubstituted tetrahydropyrans from functionalised 5-hexen-1-ols has been developed. Free radical addition of para-toluenesulfonyl iodide to the hexenol and DBU-mediated elimination of HI from the intermediate β-iodosulfones gives vinyl sulfones: subsequent conjugate addition of the potassium alkoxide leads to a highly stereoselective (≥30:1) cyclisation.