A compound represented by formula (4): can be produced by adding a heterogeneous transition metal catalyst to a solution containing a compound represented by formula (3): obtained by performing a nitration reaction by adding a nitrating agent to a solution containing a compound represented by formula (2): obtained by oxidizing a compound represented by formula (1): with hydrogen peroxide in the presence of sodium tungstate and a saturated C8 carboxylic acid, then adding water to the resultant mixture, and separating the resultant solution.