Method for preparing deuterated imidazole diketone compound

Disclosed is a method for preparing a deuterated imidazole diketone compound, comprising the following steps: (1) using a compound of formula (I) and a compound of formula (II) as raw materials to obtain a compound of formula (III) by means of a substitution reaction; (2) carrying out an esterification reaction of carboxyl groups in the compound of formula (III) to obtain a compound of formula (IV); (3) carrying out a cycloaddition reaction of the compound of formula (IV) and a compound of formula (V) to obtain a compound of formula (VI); (4) carrying out a deesterification reaction of the compound of formula (VI) to obtain a compound of formula (VII); and (5) using the compound of formula (VII) and a compound of formula (VIII) as raw materials, by an amide-forming condensation reaction, to obtain the deuterated imidazole diketone compound as represented by formula (IX). As compared to the existing methods, the method of the present invention is safer, consumes less solvent, and reduces waste thereby minimizing environmental impacts, shortens the production cycle, and increases throughput and total yield, and therefore has broad market prospects.