N-Formylmorpholine → 8-methoxy-4H-benzo[1,3]dioxine-6-carbaldehyde

Temperature

-72 °C

To 500 ml of a THF solution containing 31.2 g of 6-bromo-8-methoxy-4H-benzo[1,3]dioxine there was added dropwise 55 ml of n-butyllithium (2.55 M, hexane solution) at −70° C. under a nitrogen atmosphere. After stirring for 30 minutes at −72° C., 20 ml of N-formylmorpholine was added and the temperature was raised from −78° C. to 0° C. over a period of 30 minutes. A saturated ammonium chloride aqueous solution was added to the reaction mixture and extraction was performed with ethyl acetate. The organic layer was dried over anhydrous magnesium sulfate. The desiccant was filtered out and the filtrate was concentrated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate-heptane system) to obtain the target compound (21.28 g) as a colorless solid.

1. temperaturethe temperature was raised from −78° C. to 0° C. over a period of 30 minutes
2. dry with materialThe organic layer was dried over anhydrous magnesium sulfate
3. filtrationThe desiccant was filtered out
4. concentrationthe filtrate was concentrated under reduced pressure
5. customThe residue was purified by silica gel column chromatography (ethyl acetate-heptane system)

ORD record

ord-fde413a262e64279a265967de707b7f9

Source dataset

uspto-grants-2010_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07807690B2