Preparation method of anti-depression drug 1-[2-(2,4-dimethylphenylthio)phenyl]piperazine

The invention relates to a preparation method of an anti-depression drug 1-[2-(2,4-dimethylphenylthio)phenyl]piperazine (VI). The method comprises the following steps: condensing an initial raw material 2,4-dimethylthiophenol (I) and t-butyl 2-X halogenated phenyl carbamate (II) to generate t-butyl 2-(2,4-dimethylphenylthioalkyl) phenyl carbamate (III), carrying out Boc group removal on the t-butyl 2-(2,4-dimethylphenylthioalkyl) phenyl carbamate (III) in a proper organic solvent solution of hydrogen chloride to obtain 2-(2,4-dimethylphenylthioalkyl)aniline hydrochloride (IV), and carrying out ring closing on the 2-(2,4-dimethylphenylthioalkyl)aniline hydrochloride (IV) and bis(2-chloroethyl)amine hydrochloride (V) to generate 1-[2-(2,4-dimethylphenylthio)phenyl]piperazine (VI). The preparation method has the advantages of concise technology, economy, environmental protection, and suitableness for industrial production.