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1. Potassium hydroxide (KOH) pellets are added to a reaction system containing a water (H2O)/isopropanol (IPA) mixture of 2-(cyclopropylamino)nicotinonitrile under vigorous stirring (45% potassium hydroxide solution may also be used instead). An exothermic phenomenon from room temperature to 40 °C was observed during the reaction. 2. The temperature of the reaction system was raised to 80°C and maintained under reflux conditions for about 12 hours. The progress of the reaction was monitored by high performance liquid chromatography (HPLC) and after complete consumption of the feedstock, the mixture was cooled down to 0-5 °C and the pH was adjusted to about 6 by slow dropwise addition of 37% hydrochloric acid (HCl) while controlling the temperature below 10 °C. 3. The product, 2-cyclopropylidene, was added to the reaction system at room temperature. 3. The product 2-cyclopropylaminonicotinic acid (2-CAN) precipitated as a white solid and was separated by vacuum filtration. The wet cake was washed with minimal water and dried under vacuum at 70-80 °C to a constant weight. The final product 2-CAN was 23.40 g in 91% yield.

[1] Patent: WO2016/118586, 2016, A1. Location in patent: Page/Page column 30
[2] Patent: US2004/2603, 2004, A1. Location in patent: Page 3
[3] Green Chemistry, 2017, vol. 19, # 13, p. 2986 - 2991