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

Temperature

-72 °C

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

ORD record

ord-557213893cf34859bb620a61aa225023

Source dataset

uspto-grants-2011_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07928228B2