Preparation method of nemategravir intermediate

The present invention relates to the field of chemical drug synthesis, and particularly discloses a nemategravir intermediate preparation method, which comprises: (1) carrying out a reduction cyclization reaction on a raw material (2S, 4R)-2-((t-butoxycarbonyl) amino)-4-(cyanomethyl) dimethyl glutarate under the action of a potassium borohydride/cobalt chloride system, extracting, washing, and drying to obtain a nemategravir intermediate product; (2) carrying out ammonolysis reaction in the presence of an ammonia methanol solution at a relatively low temperature, and then filtering to prepare an isopropanol solution of a compound (III), (3) dropwise adding acetyl chloride into isopropanol to prepare an isopropanol solution of hydrogen chloride, adding the compound (III) into the prepared isopropanol solution of hydrogen chloride, and carrying out reaction at a relatively high temperature to obtain a compound (II); and carrying out deprotection and salt forming reaction at the disclosure ...