Efficient, highly diastereoselective MS 4 Å-promoted one-pot, three-component synthesis of 2,6-disubstituted-4-tosyloxytetrahydropyrans via Prins cyclization

• Naseem Ahmed and
• Naveen Kumar Konduru

Beilstein J. Org. Chem. 2012, 8, 177–185, doi:10.3762/bjoc.8.19

• -hydroxytetrahydropyran in excellent yields (95–96%). Keywords: aromatic homoallylic alcohols; 2,6-disubstituted-4-tosyloxytetrahydropyrans; MS 4 Å; Prins cyclization; PTSA; Introduction Substituted tetrahydropyrans are common structural motifs in numerous biological molecules and natural products that include

• conclusion, we have reported a simple and efficient one-pot three-component synthesis of highly diastereoselective and functionalized 2,6-disubstituted-4-tosyloxytetrahydropyrans via Prins cyclization. An aromatic homoallylic alcohol, an aromatic/aliphatic aldehyde, and p-toluenesulfonic acid (catalyst and

• reagent) are reacted in the presence of MS 4 Å in dichloromethane at reflux to afford 2,6-disubstituted-4-tosyloxytetrahydropyrans in excellent yields (72–96%) within short reaction times (20–90 min). The MS 4 Å promoted synthesis proved to be versatile enough to provide an array of symmetrical and