Method for preparing 2-amino-5-chloro-2',6'-difluorobenzophenone

The invention discloses a method for preparing 2-amino-5-chloro-2',6'-difluorobenzophenone. The method comprises the following steps of performing substitution reaction on 2-nitryl-5-chlorobenzaldehyde and m-difluorobenzene which serve as initiative raw materials under the action of n-butyl lithium to obtain 2-nitryl -5-chloro-2',6'-difluoro behzhydrol; performing oxidizing reaction in the presence of sodium hypochlorite, sodium bicarbonate, sodium bromide and 2,2,6,6-tetramethyl piperidine oxides to obtain 2-nitryl -5-chloro-2',6'-difluorobenzophenone; and performing hydrogenation reduction under normal pressure in hydrogen gas by using raney nickel to obtain the finished product of the 2-amino-5-chloro-2',6'-difluorobenzophenone. The method has the advantages of simple process, mild reaction conditions, low cost, high yield, convenience in aftertreatment, suitability for industrialized production and high purity and stable quality of obtained products, and fully meets the requirements for use as a medical i