Synthesis
1. 1-Amino-1H-pyrrole-2-carbonitrile (18.00 g, 0.17 mol) was dissolved in water (90 mL) at 0 °C.
2. KOH (47.14 g, 0.84 mol) was slowly added to the above solution.
3. The reaction mixture was stirred at room temperature overnight.
4. The reaction mixture was cooled to -15 °C and stirring was continued for 2 hours.
5. The reaction mixture was filtered and the filter cake was retained.
6. The filtrate was extracted using a solvent mixture of DCM and MeOH (10:1, 200 mL x 10, v/v).
7. The organic phases were combined, dried with anhydrous Na2SO4, filtered and concentrated in vacuum.
8. The concentrated residue was combined with the filter cake retained in step 5.
9. The combined products were purified by silica gel column chromatography (eluent MeOH/DCM, 1:10, v/v) to afford 1-amino-1H-pyrrole-2-carboxamide as a yellow solid (13.12 g, 62% yield).
MS (ESI, cationic) m/z: 126.1 [M + H]+.
NMR (600 MHz, DMSO-d6) data not provided.
References
[1] Patent: WO2006/35061, 2006, A1. Location in patent: Page/Page column 50; 51
[2] Patent: WO2016/190847, 2016, A1. Location in patent: Paragraph 0341
[3] Patent: CN104974163, 2017, B. Location in patent: Paragraph 0514; 0515; 0516; 0517
[4] Journal of Heterocyclic Chemistry, 1994, vol. 31, # 4, p. 781 - 786
[5] Patent: CN104876935, 2017, B. Location in patent: Paragraph 0066; 0069; 0070
