How is 3-Chloro-5-methoxyisonicotinic acid (CAS: 214976-36-0) typically synthesized?

3-Chloro-5-methoxyisonicotinic acid (CAS: 214976-36-0) is commonly synthesized via the condensation of 3-chloroisonicotinic acid with methanol in the presence of an acid catalyst such as sulfuric acid. The reaction typically yields a mixture that requires purification steps including recrystallization to obtain the pure compound. The process is selective and often gives good yields, around 70-80%.