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Abstract
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Recently, magnetically nanoparticles have emerged as heterogeneous supports for catalysts in the organic transformation. Surface functionalized iron oxide magnetic nanoparticles (MNPs) are a kind of novel functional materials, which have been widely used in biotechnology and catalysis. Existence of many hydroxyl groups on the MNPs surface leads to reaction with alkoxysilane reagents and formation of Si–O bonds which support terminal functional groups available for immobilization of other substances. Magnetic separation of the magnetic nanoparticles is more effective than filtration or centrifugation, simple, economical and promising for industrial applications [1]. Proctection/deprotection of hydroxy compounds is necessary during the course of various transformations in a synthetic sequence, especially in the synthesis of fine chemicals and natural products. Amongst them, tetrahydropyranylation is more frequently used due to the remarkable stability of tetrahydropyranyl ethers under a variety of conditions such as alkaline media, alkyl lithiums, metal hydrides and also oxidative, alkylating and acylating reagents [2]. In continuation of our efforts on the development of synthetic methodologies [3], herein we report catalytic application of N-propylsulfamic acid supported onto magnetic Fe3O4 nanoparticles (MNPs-PSA) as an efficient and magnetically recoverable and reusable nanocatalyst for protection of alcohols and phenols as tetrahydropyran-ethers in good to excellent yields at room temperature in CH2Cl2 and under solvent-free conditions, Forthermore, the deprotection of THP-ethers was occurred by same catalyst in methanol at room temperature. The magnetically nanocatalyst has been characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and fourier transform infrared spectroscopy (FT-IR) . In conclusion, we developed the efficient method for the Protection/deprotection of hydroxyl groups in good to high yield using MNPs-PSA that can easily be se
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