Dimethylformamide → Tert-butyl 3-fluoro-3-(4-formylphenyl)azetidine-1-carboxylate

Temperature

-78 °C

To a stirred solution of 3-(4-bromo-phenyl)-3-fluoro-azetidine-1-carboxylic acid tert-butyl ester (5 g, 15.14 mmol, 1 eq) in dry THF (60 mL) was added n-BuLi (16.6 mL, 18.17 mmol, 1.2 eq) at −78° C. under nitrogen atmosphere. Reaction mixture was stirred for 10 minutes at −78° C. under nitrogen atmosphere. At −78° C., DMF (1.748 mL, 22.71 mmol, 1.5 eq) was added in drop wise manner over a period of 10 minutes. Resulting reaction mixture was allowed to warm to −20° C. and stirred for 3 hours at −20° C. After complete consumption of starting material, reaction was quenched with 10% NH4Cl solution (10 mL) followed by water (100 mL) and extracted with ethyl acetate (3×40 mL). Combined organic phase was washed with brine solution (50 mL), dried over anhydrous Na2SO4 and concentrated under reduced pressure to afford title compound as pale yellow thick oil (4.5 g, Crude). Crude compound was used as such for next reaction. LC-MS (m/z): 279.3 (M+H).

1. customReaction mixture
2. customResulting
3. customreaction mixture
4. temperatureto warm to −20° C.
5. stirringstirred for 3 hours at −20° C
6. customAfter complete consumption of starting material, reaction
7. customwas quenched with 10% NH4Cl solution (10 mL)
8. extractionextracted with ethyl acetate (3×40 mL)
9. washCombined organic phase was washed with brine solution (50 mL)
10. dry with materialdried over anhydrous Na2SO4
11. concentrationconcentrated under reduced pressure

ORD record

ord-bcd6f45bf86f426e8d3ce87ec1c6166f

Source dataset

uspto-grants-2015_07

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US09073912B2