Yield:67058-77-9 50%

Reaction Conditions:

with sulfuric acid;nitric acid at 0 - 20;

Steps:

349.1 Step 1

To a solution of 1H-pyrrolo[2,3-c]pyridine (1 g, 8.47 mmol) in H2S04 (5 mL) was added 69% HNO3 (533 mg, 8.47 mmol) at 0 °C. After stirred at 0 °C for 2 hrs, the reaction mixture was allowed to warm to room temperature and stirred overnight. The mixture was then poured into H20 (100 mL) and basified by NaOH powder to pH> 7. Then the mixture was extracted by EA (100 mL x3), dried over anhydrous Na2SO4, and evaporated in vacuum to afford 3-nitro-1H- pyrrolo[2,3-c]pyridine (690 mg, 50%) as a yellow solid. ‘H NIVIR (400 IVIHz, DMSO-d6): ? = 8.94 (s, 1H), 8.85 (s, 1H), 8.44 (d, J= 5.2 Hz, 1H), 8.02 (dd, J= 5.6, 1.2 Hz, 1H). MS: m/z 164.0 (M+H).

References:

WO2018/132372,2018,A1 Location in patent:Paragraph 00729