Process for producing anthranilamide compound

A process for producing an anthranilamide compound represented by the formula (I) or its salt:

• (wherein R1 is halogen, alkyl, haloalkyl, alkenyl, haloalkenyl, alkynyl, haloalkynyl, alkoxy, haloalkoxy, alkylcarbonyl, haloalkylcarbonyl, alkoxycarbonyl, haloalkoxycarbonyl, nitro, formyl or cyano, A is alkyl which may be substituted by Y, Y is C3-4 cycloalkyl which may be substituted by at least one substituent selected from the group consisting of halogen, alkyl and haloalkyl, and m is an integer of from 0 to 4), which comprises reacting a compound represented by the formula (II):
• (wherein Z is 2-pyridyl, 3-pyridyl, 4-pyridyl or benzene substituted by a nitro group, and R1, A and m are as defined above), with a brominating agent, to produce a compound represented by the formula (III):
• (wherein R1, A and m are as defined above);
• and further reacting the compound of the formula (III) with an oxidizing agent.