Dimethylformamide → 5-Chloropyridine-2-carboxaldehyde

Temperature

-15 °C

Isopropyl magnesium chloride (11.5 mL, 2 M in THF, 23 mmol) was added dropwise to a cold (−15° C.) solution of 5-chloro-2-iodo-pyridine (5 g, 20.9 mmol) in THF (35 mL). The mixture was stirred for 1 h at −15° C. DMF (2.3 g, 31.3 mmol) was added dropwise keeping the internal temperature below 0° C. The mixture was allowed to warm to rt, stirred for 1 h, cooled to 0° C., quenched by addition of a saturated aqueous solution of ammonium chloride, and extracted with EtOAc. The organic layer was washed with brine, dried (Na2SO4), filtered, and concentrated. The residue was purified by silica gel column chromatography (hexane/EtOAc, 95:5) to provide 1.1 g of the title compound. tR: 0.39 min (LC-MS 2); ESI-MS: 142 [M+H]+ (LC-MS 2); Rf=0.22 (hexane/EtOAc, 4:1).

1. customthe internal temperature below 0° C
2. temperatureto warm to rt
3. stirringstirred for 1 h
4. temperaturecooled to 0° C.
5. customquenched by addition of a saturated aqueous solution of ammonium chloride
6. extractionextracted with EtOAc
7. washThe organic layer was washed with brine
8. dry with materialdried (Na2SO4)
9. filtrationfiltered
10. concentrationconcentrated
11. customThe residue was purified by silica gel column chromatography (hexane/EtOAc, 95:5)

ORD record

ord-0a3803f34a524be0b720030fa90c5545

Source dataset

uspto-grants-2015_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08969341B2