2,2'-Bipyridine → 2-Pyridinecarboxylic acid, 4,5,6-trichloro-

A 100 mL round bottom flask equipped with a magnetic stir bar was charged with NiCl2.6H2O (105 mg, 0.442 mmol), 2,2′-bipyridine (150 mg, 0.960 mmol), DMF (15 mL) and water (2 mL). The resulting mixture was allowed to stir for 5 min, and then zinc dust (2.006 g, 30.7 mmol) was added. The reaction mixture was allowed to stir at ambient temperature for 15 min until a very dark blue/black solution was present. Solid 3,4,5,6-tetrachloropicolinic acid (2.017 g, 7.7 mmol) was added through the top of the reactor. The reaction mixture was allowed to stir at 27° C. for 5.25 h, and the crude reaction mixture was filtered through a course frit filter and washed with DMF (5 mL). The resulting filtrate was diluted with an equal volume of 10% HCl (aq) which resulted in the precipitation of a light yellow solid that was collected by filtration. The solid was collected by vacuum filtration to give the title compound (2.32 g, 81.5%) that was 61.5% pure as analyzed by calibrated HPLC.

1. customA 100 mL round bottom flask equipped with a magnetic stir bar
2. stirringto stir at ambient temperature for 15 min until a very dark blue/black solution
3. stirringto stir at 27° C. for 5.25 h
4. customthe crude reaction mixture
5. filtrationwas filtered through a course
6. filtrationfrit filter
7. washwashed with DMF (5 mL)
8. additionThe resulting filtrate was diluted with an equal volume of 10% HCl (aq) which
9. customresulted in the precipitation of a light yellow solid
10. filtrationthat was collected by filtration
11. filtrationThe solid was collected by vacuum filtration

ORD record

ord-b704c81732ff44e4aa656c9eb23586e3

Source dataset

uspto-grants-2016_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09440923B2