Preparation method of zaltoprofen

The invention belongs to the field of preparation of non-steroidal anti-inflammatory drugs and more particularly relates to a preparation method of zaltoprofen. The preparation method comprises the following steps: mixing an intermediate (II) 5-(1-carboxyethyl)2-thiophenyl phenylacetic acid with concentrated sulfuric acid and phosphoric acid in a reactor and stirring to react; at a room temperature, adding ethyl acetate, ice and water into a reaction solution; collecting liquid of an ethyl acetate layer, and washing the liquid with a saturated sodium hydrogen carbonate solution and a sodium chloride solution respectively; drying, distilling and concentrating; cooling and crystallizing; filtering and eluting crystals with the ethyl acetate; drying to obtain the zaltoprofen product. The preparation method is simple to operate; the utilization rate of the raw materials and the product yield are improved, the influences on the environment are small and the preparation method is suitable for industrial production.