Process for increasing fluorochloridone cyclization synthesis yield

The present invention relates to a process for increasing the fluorochloridone cyclization synthesis yield. According to the process, N-allyl-N-dichloroacetyl-m-trifluoromethyl aniline is adopted as a raw material, anhydrous 1,2-dichloroethane is adopted as a solvent, the solvent amount is controlled at 10-45 ml/g raw material, cuprous chloride is adopted as a main catalyst, 2,2'-bipyridine is adopted as a co-catalyst, a molar ratio of the main catalyst to the co-catalyst is controlled at 1:1, the catalyst use amount is 10-30 mol%, the reaction temperature is controlled at 70-90 DEG C, the reaction is performed until the raw material disappears, and the reaction solution is subjected to silica gel column filtration and dichloromethane elution so as to prepare the fluorochloridone. Compared with the process in the prior art, the process of the present invention has the following characteristics that: the raw material drug with the fluorochloridone content of more than or equal to 95% can be obtained only through the short silica gel column filtration and without distillation, re-crystallization and other purifications, the trans-cis ratio is more than or equal to 3:1, and the cyclization yield is more than or equal to 95%.