Alpo4and Alpo4-Al2O3as New Heterogeneous Catalysts for the Solvent-Free Tetrahydropyranylation of Alcohols and Phenols

Abstract
OH-protection of alcohols and phenols by heating the hydroxylated compound with 3,4-dihydro-2H-pyrane in the presence of an AlPO4 or AlPO4-Al2O3 heterogeneous acid catalyst is described. Isolated yields, not optimized, were in the range 50–99%.