Preparation method of cefprozil mother nucleus APCA

The invention relates to a preparation method of cefprozil mother nucleus APCA, which comprises the following steps: (1) mixing and reacting GCLE, sodium iodide and triphenylphosphine in a dichloromethane-water system in a dark place, separating out a water phase, adding sodium hydroxide into a dichloromethane phase to form a wittig reagent, and adding acetaldehyde to react under the protection of nitrogen to obtain a reaction solution containing GPRE; (2) replacing the solvent of the reaction liquid containing GPRE with ethyl acetate, then adding zinc chloride for reaction, filtering after the reaction is finished, extracting the filtrate with a hydrochloric acid solution to obtain an ethyl acetate phase, and evaporating the ethyl acetate phase to remove the solvent to obtain GPRE; and (3) mixing GPRE with a decarboxylation protection catalyst and phenol for reaction, uniformly mixing with butyl acetate and a NaHCO3 solution, standing for layering to obtain a water phase, and adding penicillin acylase-750 in