Hydrochloric Acid → 3-Acetyl-2-chloropyridine

Temperature

0 °C

To a solution of 2-chloro-3-cyanopyridine (139 mg) in tetrahydrofuran (5 mL) at 0° C. was added dropwise a solution of MeMgBr (3M in ether, 0.67 mL). The resultant mixture was warmed to room temperature and stirred for 3 hr. The reaction solution was cooled to 0° C. and to it was added aqueous HCl solution (2M, 5 mL). The reaction solution was then stirred an additional 16 hr at room temperature and then neutralized by the addition of saturated sodium bicarbonate (NaHCO3) solution. The reaction solution was filtered to remove any precipitates and the filtrate was washed with ethyl acetate (3×10 mL) and aqueous brine (NaCl) solution (10 mL). The organic layer was dried over sodium sulfate (Na2SO4), filtered and concentrated in vacuo to give 3-acetyl-2-chloropyridine as a yellow powder which was used without further purification. The title compound (3-Methyl-1H-pyrazolo[3,4-b]pyridine) was synthesized from 3-acetyl-2-chloropyridine according to the procedure outlined in Example 2.

1. stirringThe reaction solution was then stirred an additional 16 hr at room temperature
2. filtrationThe reaction solution was filtered
3. customto remove
4. customany precipitates
5. washthe filtrate was washed with ethyl acetate (3×10 mL) and aqueous brine (NaCl) solution (10 mL)
6. dry with materialThe organic layer was dried over sodium sulfate (Na2SO4)
7. filtrationfiltered
8. concentrationconcentrated in vacuo

ORD record

ord-8754a02350a14c0d9de94e18fed28792

Source dataset

uspto-grants-2016_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09296740B2