The invention discloses a photochemical synthesis method of a
vonoprazan intermediate, and belongs to the technical field of
drug intermediate synthesis, the synthesis method comprises the following steps: (1) 2-bromo-1-(2-fluorophenyl) ethyl-1-
ketone and
acetaldehyde are subjected to a
white light irradiation reaction under the action of a
photosensitizer and alkali to obtain 4-(2-fluorophenyl)-4-oxobutyraldehyde; (2) carrying out a Paal-Knorr
condensation reaction on the 4-(2-fluorophenyl)-4-oxobutyraldehyde and
ammonium acetate under the action of an acid catalyst and a dehydrating agent, so as to obtain 2-(2-fluorophenyl)-1H-
pyrrole; (3) carrying out
formylation reaction on the 2-(2-fluorophenyl)-1H-
pyrrole and 1, 1-dichloromethoxymethane under the action of a Lewis acid catalyst, so as to obtain a
vonoprazan intermediate; the method has the advantages of cheap and easily available raw materials, high product yield, safe and simple process, mild
reaction conditions and low cost, and is suitable for industrial production.