Florol synthesis via Prins cyclization over hierarchical beta zeolites

A set of hierarchical beta zeolites with variable Si/Al ratios, nanoparticle sizes, textural and acidic properties was prepared using a hydrothermal treatment concentrated alkali metal-free protic acid-containing zeolite gel-precursor. The obtained catalysts were investigated in the Prins cyclization isovaleraldehyde isoprenol yielding commercially valuable tetrahydropyranol (Florol). highest yield desired product (55.4%) achieved over catalyst possessing moderate acidity, developed mesoporosity (Vmeso 0.60 cm3/g) high external surface area (290 m2/g). Preferable formation substituted weak- medium-strength Brønsted acid sites, on one hand, generation undesired dehydration products mainly strong other occurring parallel routes supported by kinetic analysis reaction network.