Zirconium Dodecylphosphonate: Selective and Constructive Catalyst for Preparation of 2-Alkyl Benzoxazoles from Aliphatic Carboxylic Acids

In this study, zirconium dodecylphosphonate was synthesized by the reported method in scientific literature. 2-Alkylbenzoxazoles were prepared from aliphatic carboxylic acids and 2-aminophenol in the presence of this catalyst under solvent-free conditions at 100 degrees C. Their structures were recognized by IR, H-1 NMR, and C-13 NMR. Then, we used aromatic carboxylic acids in the similar reaction. But, the results show aromatic carboxylic acids don't react with 2-aminophenol. So, this method introduces a selective and constructive method for synthesis of 2-alkyl benzoxazoles without salt formation. On the other hand, this research offers several advantages such as high yields, good reaction times, easy work-up and use of a safe catalyst.