Structural and orthoselectivity study of 2-hydroxybenzaldehyde using spectroscopic analysis

The orthoselectivity and high yield are two significant subjects which should be studied more in the process of hydroxybenzaldehydes or salicylaldehyde production. In this work, salicylaldehyde was synthesized by the reaction of formaldehyde and phenol magnesium methoxide complex, in an anhydrous medium. In order to achieve a selectively orthoformylated product, at first the hydroxyl group of phenol was rearranged by magnesium methoxide. The phenol magnesium salt was then formylated by paraformaldehyde. Impurities of the resulted salicylaldehyde were removed by several steps of liquid extracting via water and acid washing. The spectroscopic data of FT-IR, 1H NMR (500 MHz), and GC/MS on the final product were recorded and interpreted. The results of FT-IR spectrum and integration value of 1H NMR spectrum imply on the high conversion of reaction. The GC/MS spectrum also shows that the amounts of by products are low enough.