Method for preparing rocuronium bromide intermediate

The invention discloses a method for preparing a rocuronium bromide intermediate, and belongs to the technical field of rocuronium bromide intermediate preparation. The preparation method comprises the following steps: carrying out oxidation reaction on 17-acetoxy-5alpha-androstane-2, 16-diene serving as a raw material and a first oxidant to generate a primary intermediate 2, 3-epoxide, carrying out reaction on the primary intermediate 2, 3-epoxide and morpholine to open the ring of epoxy so as to introduce morpholinyl into the 2-site to produce a morpholinyl intermediate, adding a second oxidant to react to obtain an intermediate 16, 17-epoxide, and separating the intermediate 16, 17-epoxide from the intermediate 16, 17-epoxide. The intermediate 16 and 17-site epoxide is subjected to ester group hydrolysis under an alkaline condition to obtain a hydrolysate, the hydrolysate reacts with pyrrolidine, pyrrolyl is introduced into the 16 site to obtain a carbonyl compound, and finally 17-site carbonyl of the carb