Synthesis of cis and trans 2,4,6-Tetrahydropyranols via Prins-Type Cyclization and Mitsunob Inversion

Prins cyclization of substituted homoallylic alcohol with aryl/aliphatic aldehyde in the presence of a boron trifluoride etherate and trifluoro acetic acid followed by hydrolysis of the resulting trifluoroacetate give substituted cis 2,4,6-tetrahydropyranol products 1-5(c), then Mitsunobu inversion subsequent methanolysis furnished trans 2,4,6-tetrahydropyranol products 1-5(d) stereoselectively in good yield.Our present work reports the synthesis and characterization of these 1-5(c,d) products.