Synthesis
Example 11: Synthesis of 3-aminomethyl-2-methoxypyridine (25)
To a round bottom flask was added 2-methoxy-3-pyridinecarboxaldehyde (24) (0.44 g, 3.23 mmol), ammonium acetate (1.24 g, 16.15 mmol) and sodium cyanoborohydride (0.61 g, 19.69 mmol). After replacing the atmosphere in the flask with argon, dry methanol (50 mL) was added via syringe. The reaction mixture was stirred for 2 days and subsequently concentrated under reduced pressure to remove the methanol. To the residue, water (25 mL) was added and the pH was adjusted to 2 with concentrated hydrochloric acid. two extractions with ethyl acetate were performed to remove the alcoholic by-products. Subsequently, the pH of the aqueous phase was adjusted to 10 with sodium hydroxide pellets, saturated with sodium chloride and extracted twice with dichloromethane and once with ethyl acetate. The organic phases were combined, dried and concentrated under reduced pressure to give 3-aminomethyl-2-methoxypyridine (25) (0.31 g, 69% yield).
References
[1] Patent: WO2006/108103, 2006, A1. Location in patent: Page/Page column 32
[2] Patent: US2008/119496, 2008, A1. Location in patent: Page/Page column 11
[3] Patent: WO2008/60301, 2008, A1. Location in patent: Page/Page column 31