Method for preparing cefdinir

The invention relates to a method for preparing cefdinir, which comprises the following steps of: performing silanization protection of carboxyl on 7-amino-3-vinyl-3-cephem-4-carboxylic acid (7-AVCA), performing acylation reaction on the 7-AVCA and cefdinir active ester (CAEM) to obtain acetyl cefdinir with carboxyl subjected to silanization protection, performing hydrolysis or alcoholysis or simple salifying reaction on the acetyl cefdinir to obtain acetyl cefdinir dicyclohexylamine salt, and hydrolyzing the salt to obtain the cefdinir. Compared with the prior art, the method improves the purity of the finally obtained cefdinir product and improves the yield of the cefdinir product at the same time, and the obtained product can be directly used as a raw material medicament for clinical use; and moreover, the method also has the advantages of simple operation, quick reaction, short production period, low production cost and the like.