Regio and Stereoselectivity in the Synthesis of a 2,2,6,6 Tetrasubstituted Tetrahydropyran from Geranyl Acetate. Synthesis of Dihydropyrans - Urones, Julio G; Díez, David; Marcos, Isidro S; Basabe, Pilar; Garrido, Narciso M; Escarcena, Ricardo; Lithgow, A M; Dominguez, M F; Sánchez, J M (Synlett, 1995)