20010-99-5

2-(Aminomethyl)pyrazine is a useful synthetic intermediate. It is used to synthesize pyrazolo[4,3-c]pyridinediones as orally bioavailable NADPH oxidase isoform 4 inhibitors for the treatment of idiopathic pulmonary fibrosis. It is also used to prepare pyrazolyl-indoles with the abilities to induce T-cell kinase inhibition.

The general procedure for the synthesis of 2-aminomethylpyrazine from 2-cyanopyrazine is as follows: the method described in the literature (JP A 2001-894594) was referred to as follows. The raw material 2-cyanopyridine was purchased from Sigma-Aldrich Co. LLC. 1.05 g (10 mmol) of 2-cyanopyridine and 100 mg of 60 wt% Ni/SiO2 catalyst were placed in 20 mL of toluene and loaded into an autoclave (model 5U5316), followed by argon replacement of the air in the autoclave. The reaction was pressurized to 50 atm under hydrogen atmosphere and stirred at 140 °C reaction temperature for 4 hours. Upon completion of the reaction, the reaction solution was filtered to remove the catalyst and the filtrate was concentrated to quantitatively obtain the target product 2-aminomethylpyridine (2-AMPZ). The product was characterized by 1H-NMR (399.78 MHz, CDCl3): δ 8.60-8.45 (m, 3H), 4.07 (s, 2H), 1.79 (br, 2H).

[1] Patent: US2015/31920, 2015, A1. Location in patent: Paragraph 0150; 0151; 0152
[2] Patent: EP2230241, 2010, A1. Location in patent: Page/Page column 18
[3] Patent: EP2404921, 2012, A1. Location in patent: Page/Page column 9
[4] Patent: US2012/65209, 2012, A1. Location in patent: Page/Page column 9
[5] Patent: TWI522358, 2016, B. Location in patent: Page/Page column 15; 18