TETRAHEDRON LETTERS Tetrahedron Letters 39 (1998) 8159-8162 Pergamon Zirconium Sulfophenyl Phosphonate as a Heterogeneous Catalyst in Tetrahydropyranylation of Alcohols and Phenols.* Massimo Curini,** Francesco Epifano, Maria Carla Marcotullio and Ornelio Rosati lstituto di Chimica Organica, Facolt~ di Farmacia, Universitil degli Studi, Via del Liceo, 06123 Perugia, Italy Umberto Costantino Dipartimento di Chimica, Universitil degli Studi, Via Elce di Sotto, 06123 Perugia, Italy Received 29 May 1998; ~cepted 28 August 1998 Abstract: Zirconium Sulfophenyl Phosphonate Zr(O3PCH3)I.2(O3PC6I-I4SO3H)0.8 was found to be an efficient heterogeneous catalyst for the tetr~ydropyranylation of alcohols and phenols. © 1998 Elsevier Science Ltd. All rights reserved. Keywords: Alcohols, Phenols, Protecting group, Zirconium and compounds. It is now well established that many acidic and basic solids act as catalysts or promoters in liquid phase organic synthesis. 1 There are many examples of better yields, shorter reaction times, and even higher selectivities achieved as the result of reactions carried out with heterogeneous catalysts under reaction conditions milder than those employed in conventional homogeneous synthetic methods. Heterogeneous catalysts are generally inorganic solids, clays and modified clays, 2 zeolites, metal oxides,3 or organic polymers such as functionalized styrene-divinylbenzene resins. 4 We have recently found that inorgano-organic layered solids belonging to the emerging class of metal (IV) phosphonates5, 6 and bearing suitable functional groups, are excellent catalysts for organic synthesis, since they combine the properties of a stable inorganic backbone with the flexibility of the organic derivatives. Layered zirconium methane-sulfophenyl phosphonate,7 bearing strongly acidic-C6I-I4SO3H groups anchored to the inorganic layers, has proved to be an excellent heterogeneous catalyst of acid-catalysed reactions (deprotection of nitrogen containing derivatives,8 conversion of 1,3-dithiolanes and 1,3-dithianes to the corresponding carbonyl compound,9 protection of alcohols as TMS- derivativel0). It seemed of interest to test the catalyst for tetrahydropyranylation, an important * Dedicated to the memory of Prof. Paolo Ceccherelli. Corresponding author. Entail: c u m u ~ p g . t t 0040-4039/98/$ - see front matter © 1998 Elsevier Science Ltd. All rights reserved. PH: S0040-4039(98)01817-6