5-Chloro-1H-pyrazolo[4,3-b]pyridine

6- Chloro-2-methylpyridin-3-amine (12.8 g, 0.09 mol) was dissolved in chloroform (500 mL). Acetic anhydride (34.0 mL, 0.36 mol) and potassium acetate (10.6 g, 0.11 mol) were added and the mixture was stirred at 60°C for 2 hours. Subsequently, isoamylnitrite (27.8 mL, 0.21 mol) and 1 , 4, 7, 10, 13, 16-hexaoxacyclooctadecane (2.4 g, 8.90 mmol) were added and the reaction mixture was stirred at 60°C overnight. The solvent was removed, the crude was dissolved in methanol (225 mL) and water (50 mL), it was cooled to 0°C and potassium carbonate (45 g) was added portionwise. The mixture was stirred at 0°C for 10 minutes and then at room temperature for 3 hours. Water was added to the crude and the resulting mixture was stirred at room temperature for 1 hour. The precipitate was filtered and washed with water and hexanes. The solid thus obtained was dried in the vacuum oven overnight at 50°C to yield the title compound (13.6 g, 97percent) as a solid. LRMS (m/z): 154, 156 (M+1 , M+3)In the ice bath, An aqueous solution of sodium nitrite (4.8 g) was slowly added dropwise to a solution of 2-methyl-3-amino-6-chloropyridine (10 g) in acetic acid.After the addition is completed, slowly warm up to room temperature.The reaction was overnight.In the ice bath, With a saturated sodium carbonate solution, the reaction mixture will have a pH of about 8, Extract with ethyl acetate, The combined organic phases are washed with saturated brine, Dried over anhydrous sodium sulfate, Filter and concentrate the filtrate in vacuoThe residue was purified by column chromatography on silica gel, The title compound (1.69 g) was isolated.

Molecular Weight:153.57
XLogP3:1.5
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:2
Exact Mass:153.0093748
Monoisotopic Mass:153.0093748
Topological Polar Surface Area:41.6
Heavy Atom Count:10
Complexity:130
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes