A production method of a compound represented by formula (2):

(wherein ring A represents a benzene ring or a 6-membered aromatic heterocycle; R 1 represents a hydrogen atom, a C 1-6 alkyl group, a halogen atom, a nitro group, an amino group, a mono-C 1-6 alkylamino group, or a di-C 1-6 alkylamino group; and at least one of R 2 , R 3 , and R 4 represents a methoxy group, and the rest each represents a hydrogen atom, a C 1-6 alkyl group, a halogen atom, a nitro group, an amino group, a mono-C 1-6 alkylamino group, or a di-C 1-6 alkylamino group),
comprising reacting a compound represented by formula (1):

(wherein ring A and R 1 , R 2 , R 3 , and R 4 are the same as defined above) with a Lewis acid selected from BF 3 , TiCl 4 , and AlCl 3 in esteric, ketonic or amidic solvents selected from ethyl acetate, methyl acetate, butyl acetate, isobutyl acetate, acetone, 2-butane, cyclohexane, cyclopentane, dimethylformamide, and dimethylacetamide, with the proviso that when the Lewis acid is BF 3 , an alkali metal bromide or an alkali metal iodide coexists.