Stabilisation of the thromboxane ring system by electron-withdrawing substituents: synthesis and attempted cyclisation of substituted tetrahydropyran-2,4-diols

Abstract

The hetero Diels–Alder reaction of trifluoromethyl ketones and 1-benzyloxy-3- trimethylsilyloxybutadiene is developed as a route to 4-hydroxytetrahydropyranyl acetal derivatives. Several 6,6-disubstituted tetrahydropyran-2,4-diols have been prepared, and their anomeric equilibria measured by ¹H NMR spectroscopy. Attempted cyclodehydration to 2,6-dioxabicyclo[3.1.1]heptanes (thromboxane A₂ analogues) failed under various conditions.