Example 10: Synthesis of 4-(2-pyridyl)benzoic acid
In a 100 mL jacketed reactor, 200 mL of acetic acid, 0.05 g of manganese(II) acetate, 1.74 g of sulfuric acid, and 3.0 g of 2-(4-methylphenyl)pyridine were sequentially added. The reaction mixture was cooled to 16°C, followed by slow passage of 4.0 g of ozone over 60 minutes. Upon completion of the ozonolysis reaction, the reaction was purged with nitrogen to remove residual ozone from the solvent. The reaction mixture was analyzed by HPLC or GC, which showed that the residue of 2-(4-methylphenyl)pyridine was <0.1% and the yield of 4-(2-pyridyl)benzoic acid was 94-97%.
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