Method for synthesizing azithromycin intermediate through one-pot method

The invention discloses a method for synthesizing an azithromycin intermediate by a one-pot method, which is characterized in that erythromycin thiocyanate is used as an initial raw material, oximation, rearrangement and reduction reaction are sequentially performed to obtain the azithromycin intermediate 9-deoxy-9a-aza-9a-cis-erythromycin A, and the three steps of reaction are completed by the one-pot method. Malonyl chloride and N, N-dimethyl-n-octylamine are introduced in the rearrangement reaction step and serve as a rearrangement reagent and an acid-binding agent respectively, malonyl chloride can be quenched after water is added, no solid is separated out after dichloromethane is subjected to reduced-pressure evaporation, and the next-step reaction can be directly carried out; the N, N-dimethyl-n-octylamine can be used as a cationic surfactant to play a defoaming role in the reduction reaction, and the reaction process is not influenced after the two materials enter the reduction reaction; a hydrolysis