Hydrochloric Acid → 2-Hydroxy-4-[(5-nitro-2-pyridinyl)oxy]benzonitrile

Temperatur

110 °C

In a vial 2,4-dihydroxybenzonitrile (300 mg, 2.2 mmol), 2-chloro-5-nitropyridine (351.96 mg, 2.22 mmol) and K2 CO3 (920 mg, 6.62 mmol) were dissolved in DMF (5 mL). The reaction was heated for 1 hour under microwave irradiations (Set Temperature: 110° C.). The reaction mixture was diluted with Et2O and water, acidified with aqueous 1N HCl until pH=2, the phases were separated and the organics were dried over Na2SO4. The solid was filtered out and the solvent was removed affording crude 2-hydroxy-4-[(5-nitro-2-pyridinyl)oxy]benzonitrile (664 mg) as a brown solid. To a solution of this crude in dry DMF (5 mL) potassium carbonate (460 mg, 3.33 mmol) and isopropyl bromide (313 μL, 3.33 mmol) were added and the reaction mixture was stirred overnight at 50° C. The reaction was diluted with brine (10 mL) and extracted with ethyl acetate (2×20 mL). The organic layer was dried (Na2SO4), filtered and evaporated and the residue was purified by flash chromatography on silica gel (SNAP 25 g) eluting from 100:0 to 75:25 cyclohexane/ethyl acetate affording the title compound (260 mg) as white solid.

1. customthe phases were separated
2. dry with materialthe organics were dried over Na2SO4
3. filtrationThe solid was filtered out
4. customthe solvent was removed

ORD-Eintrag

ord-27c99b56750244d88c3fe4af545792b1

Quelldatensatz

uspto-grants-2014_05

DOI

10.6084/m9.figshare.5104873.v1

Patentnummer

US08722695B2