A New Approach to the Synthesis of Acylals Using Nano Sawdust/BF3 as Green Catalyst at Room Temperature under Solvent-free Condition

The selective protection and deprotection of carbonyl groups are one of the most important and versatile modern organic reactions [1]. The protection of aldehyde compounds such as acetals and acylals are one of the most important reactions in multi-step syntheses [2]. Among different methods for the protection of aldehyde, geminal diacetates (acylals) are appropriate candidates for this aim. Many methods have been developed for the chemoselective synthesis of 1,1-diacetates using various catalysts such as SiO2.CTB, Fe3O4@SiO2-imid-PMAn [3]. Herein, we wish report the synthesis of acylals using nano sawdust/BF3 under solvent-free condition at room temperature (Scheme 1). The advantages of this work are simple work-up, short reaction time and high yeilds. The acylation of various aliphatic and aromatic aldehydes with acetic anhydride were done successfully in the presence of nano sawdust/BF3 as an eco-friendly and green catalyst.