Toluene → 5-Bromo-2-(trifluoromethyl)pyridine-4-carbaldehyde

Temperatur

-10 °C

To 5-bromo-N-methoxy-N-methyl-2-(trifluoromethyl)pyridine-4-carboxamide (21 g, 67.1 mmol) in THF (200 mL) was added DIBAL-H in toluene (1M, 73.8 mL, 73.8 mmol) through a syringe at −78° C. The reaction was stirred for 40 minutes while it was warmed to −10° C. The reaction was diluted with EtOAc (100 mL) and was quenched with 1N HCl solution (150 mL). The reaction mixture was filtered on a Celite and silica gel bed. The layers were separated and the organic layer was partitioned with saturated. NaHCO3 and then brine. The organic layer was dried over Na2SO4, filtered and concentrated in vacuo. The crude reaction was purified by column chromatography to yield 5-bromo-2-(trifluoromethyl)pyridine-4-carbaldehyde (13.1 g, 51.6 mmol). 1H NMR (500 MHz, CDCl3) δ10.2 (s, 1H), 9.04 (s, 1H), 8.84 (s, 1H).

1. customwas quenched with 1N HCl solution (150 mL)
2. filtrationThe reaction mixture was filtered on a Celite and silica gel bed
3. customThe layers were separated
4. customthe organic layer was partitioned with saturated
5. dry with materialThe organic layer was dried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe crude reaction
9. customwas purified by column chromatography

ORD-Eintrag

ord-072f1a45fd0345e8bd2e74ce122d0a65

Quelldatensatz

uspto-grants-2016_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US09346825B2