A method is provided for producing a compound represented by formula (3), wherein n is 1, 2, 3 or 4, by mixing a compound represented by formula (2), a tri(C1-C3 alkyl)silyl(C1-C4 perfluoroalkane) and a fluoride. A method for producing the compound represented by formula (3) contains a step for producing the compound represented by formula (2) by an intramolecular dehydration condensation of a compound represented by formula (1) and by a step for mixing the compound represented by formula (2), a tri(C1-C3 alkyl)silyl(C1-C4 perfluoroalkane) and a fluoride.