Extracurricular laboratory: Synthetic route of 2-Methoxy-3-(trifluoromethyl)pyridine

The chemical industry reduces the impact on the environment during synthesis 121643-44-5, I believe this compound will play a more active role in future production and life.

Reference of 121643-44-5, With the rapid development and complex challenges of chemical substances, the synthesis of new drugs is usually one of the most effective ways to increase yield.121643-44-5, name is 2-Methoxy-3-(trifluoromethyl)pyridine, molecular formula is C7H6F3NO, molecular weight is 177.1239, as common compound, the synthetic route is as follows.

Intermediate 1 : 5-Bromo-2-methoxy-3-trifluoromethyl-pyridineTo 2-methoxy-3-(trifluoromethyl)pyridine (20.0 g, 1 13.0 mmol) and 1 ,3-dibromo-5,5- dimethylimidazolidine-2,4-dione (43.6 g, 152.0 mmol) was added TFA (80 mL) and the resulting mixture stirred at rt for 18h under argon. The TFA was removed in vacuo (50 mbar, 45C) and the residue suspended in tert-butyl methyl ether (200 mL). The resulting colourless solid was removed by filtration and washed with tert-butyl methyl ether (50 mL). The filtrate was concentrated in vacuo and suspended in EtOAc (50 mL) The insoluble colourless solid was removed by filtration and washed with EtOAc (50 mL).The filtrate was concentrated in vacuo, diluted with heptane/ tert-butyl methyl ether (5/1 , 20 mL) and the insoluble colourless solid was removed by filtration. The filtrate was purified by column chromatography on silica gel with heptane / EtOAc, 100/0 to 90/10. The crude product was filtered through a plug of NaHC03 (20g) and the filtrate evaporated in vacuo to give a golden oil (27.9 g). The oil was dissolved in heptanes (20 mL) and purified by filtered through a plug of silica gel (80 g), eluting with heptane to give 5-bromo-2-methoxy-3-(trifluoromethyl)pyridine as a colourless oil (22.5g, 74% yield). 1H-NMR (400 MHz, DMSO-d6, 298 K): delta ppm 4.03 (s, 3H) 7.95 (d, 1 H) 8.4 (d, 1 H).

The chemical industry reduces the impact on the environment during synthesis 121643-44-5, I believe this compound will play a more active role in future production and life.

Reference:
Patent; NOVARTIS AG; FERNANDES GOMES DOS SANTOS, Paulo Antonio; HOeGENAUER, Klemens; HOLLINGWORTH, Gregory; SOLDERMANN, Nicolas; STOWASSER, Frank; TUFILLI, Nicola; ZECRI, Frederic; WO2013/1445; (2013); A1;,
Pyridine – Wikipedia,
Pyridine | C5H5N – PubChem