BEA zeolite was synthesized under hydrothermal condition and modified with various amounts of chlorosulphonic acid. It was characterized by XRD, XRF, FT-IR, BET, thermogravimetric analysis and SEM techniques. Catalytic activity of BEA-SO3H was tested for the synthesis of 1,1-diacetates from a variety of aromatic and aliphatic aldehydes including those carrying electron donating or withdrawing substituents by acetic anhydride. At optimized conditions, The BEA-SO3H (28 wt.%) catalyst showed good yield at very short time for the synthesis and deprotection of 1,1-diacetates. Furthermore, BEA-SO3H was found to be recyclable for the protection of aldehydes with acetic anhydride under solvent-free and room temperature conditions. This method is a green approach for the protection of aldehydes in the presence of ketones. (C) 2010 Elsevier B.V. All rights reserved.