Preparation method of monoazo disperse dye

The invention relates to a preparation method of monoazo disperse dye. The preparation method comprises the following steps: step 1): carrying out diazotization reaction on a compound as shown in a formula (I) and nitrosyl sulfuric acid under an acidic condition to obtain a diazo reaction product; (2) carrying out coupling reaction on the diazo reaction product and a coupling component shown in a formula (II) to obtain a coupling reaction product; and 3) carrying out crystal transformation on the coupling reaction product to obtain the monoazo disperse dye. The monoazo disperse dye prepared by the preparation method disclosed by the invention has the characteristics of environment-friendly process, excellent dyeing performance and high purity and yield. Furthermore, the preparation method of the monoazo disperse dye is simple and easy to implement, raw materials are easy to obtain, and the monoazo disperse dye is suitable for mass production. 本发明涉及一种单偶氮分散染料的制备方法。所述制备方法包括以下步骤：步骤1)：将式(I)所示的化合物在酸性条件下与亚硝酰硫酸进行重氮化反