How is Thieno[3,2-c]pyridine-2-carboxylic acid (CAS: 86236-37-5) typically synthesized?

Thieno[3,2-c]pyridine-2-carboxylic acid (CAS: 86236-37-5) is typically synthesized via the condensation of 2-aminothieno[3,2-c]pyridine with carboxylic acid chloride or anhydride, often under a catalytic condition with a hindered base. The yield is generally high, and the product is purified by recrystallization from appropriate solvents.