13600-43-6

533932-97-7

533932-96-6

13600-43-6

The general procedure for the synthesis of 3-cyano-4-trifluoromethylpyridine (Compound VIIb) from Compound (CAS:533932-97-7) and Compound (CAS:533932-96-6) is as follows (refer to Example 5): Step F: To a solution of 28% sodium methanol (580 mg, 3.0 mmol) in methanol (5 mL) was added a methanol solution of 3-[(4,4,4-trifluoro-3-oxo-1-butenyl)amino]-2-propenenenitrile (a mixture of IIa and IIb; 380 mg, 2.0 mmol), and the reaction mixture was stirred and then refluxed for 2 hours at room temperature. After completion of the reaction, the reaction solution was poured into water and extracted with ethyl acetate. The organic layers were combined, washed with brine, dried over magnesium sulfate and then concentrated. The resulting residue was purified by silica gel column chromatography (elution solvent: hexane/ethyl acetate = 3/1) to give 195 mg (56.5% yield) of the target compound 3-cyano-4-trifluoromethylpyridine. 1H-NMR spectrum (200 MHz, CD3OD) δ (ppm): 9.11 (1H, s), 9.03 (1H, d, J=5.1 Hz), 7.72 (1H, d, J=5.1 Hz).