Synthetic applications (II) of the tandem [2,3]-Wittig-anionic oxy-Cope rearrangement: Stereoselective trisubstituted δ-lactone and tetrahydropyran synthesis

Article abstract of DOI:10.1016/S0040-4039(97)01475-5

Di- and trisubstituted δ-lactones have been prepared by stereoselective iodolactonisation and phenylselenolactonisation of δ,ε-unsaturated carboxylic acids. The acyclic stereochemistry of the acids arises from highly stereoselective tandem [2,3]-Wittig-anionic oxy-Cope rearrangement of cinnamyl ethers with potassium hydride and 18-crown-6 in THF to give δ,ε-unsaturated aldehydes.