The method for synthesizing 2,3, 4-trihydroxybenzaldehyde is shown as follows.
This method takes pyrogallol as an initial raw material. It comprises three steps of phenolic hydroxyl protection, formylation, and deprotection: protecting two adjacent phenolic hydroxyl groups in the pyrogallol to obtain 4-hydroxybenzo[d][1,3]dioxol-2-one, then performing formylation to obtain 7-hydroxy-2-oxobenzo[d][1,3]dioxole-4-carbaldehyde, and finally removing a protecting group to get a target 2,3,4-trihydroxybenzaldehyde.