Ethers are of great importance as intermediates and products in organic synthesis, and the conversion of alcohols into ethers is one of the most important synthetic procedures.[1] Frequently used methods for the transformation of alcohols to ethers are the reactions of alcohols or their salts with different alkylating reagents, such as alkyl halides, diazomethane, and methyl trifluoromethane sulfonate. [2] The dehydration of alcohols using protonic acids Lewis acids iodine, and dimethyl sulfoxide at high temperature has also been reported.[3] However, each method has certain limitations with regard to scope and reaction conditions., In the present study, Fe (HSO4)3 as a heterogeneous, reusable, and inexpensive catalyst was used for direct synthesis of unsymmetrical ethers from alcohols. Methods: A mixture of 1-phenyl ethanol (1mmol) and 1-butanol (1mmol) was stirred in the presence of Fe (HSO4)3 (7 mol %) at 90 °C. After completion of the reaction, the reaction mixture was filtrated and the crude product was purified by thin layer chromatography. . Results: To achieve high reaction efficiency, the reaction of 1-phenyl ethanol with 1-butanol was chosen as a model reaction to investigate the applicability of Fe (HSO4)3 as catalyst in direct etherification of alcohols. The effects of different molar ratios of reactants in various solvents and different temperatures were examined on the model reaction. To explore the generality and scope of the direct etherification reaction in the presence of Fe (HSO4)3, the optimized conditions were used for the synthesis of a series of unsymmetrical ethers (scheme1). In this study, a method for direct etherification of alcohols under mild reaction conditions was developed. It is remarkable that this method offers several advantages: (i) The catalyst is stable and reusable and offers easy handling. Moreover, isolation of the product by simple filtration of the solid acid is much easier; (ii) This method gives satisfactory yields of the unsymmetrical ethers without formation of any side product.

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