Tetrahydrofuran → HCID 67241884, compound

Temperature

60 °C

To a solution of 3-bromo-7-methoxy-5H-chromeno[2,3-b]pyridin-5-one (4.50 g, 14.7 mmol) in THF (294 ml, 14.7 mmol) at 5° C. was added methylmagnesium bromide (1 M in butyl ether) (36.8 ml, 36.8 mmol). The reaction was removed from the ice bath and stirred for an additional 1 hour. TLC showed complete conversion to a lower Rf material. The reaction mixture was quenched with saturated ammonium chloride (250 mL) and to it DCM (100 mL) was added. The mixture was stirred vigorously for 30 minutes before being poured into a separatory funnel containing 300 mL of DCM. The layers were separated and the aqueous layer was extracted with DCM 2×100 mL. The combined organic layers were washed with brine, dried over Na2SO4 and filtered. TLC revealed tertiary alcohol and no olefin. The organics were concentrated under reduced pressure at 60° C. Flask was maintained at 60° C. on the rotovap for 1 hour at which point TLC and NMR show clean conversion to 3-bromo-7-methoxy-5-methylene-5H-chromeno[2,3-b]pyridine. MS m/z=304.2 [M+H]+. Calc'd for C14H11BrNO2: 304.0.

1. customThe reaction was removed from the ice bath
2. customThe reaction mixture was quenched with saturated ammonium chloride (250 mL) and to it DCM (100 mL)
3. additionwas added
4. stirringThe mixture was stirred vigorously for 30 minutes
5. additionbefore being poured into a separatory funnel
6. additioncontaining 300 mL of DCM
7. customThe layers were separated
8. extractionthe aqueous layer was extracted with DCM 2×100 mL
9. washThe combined organic layers were washed with brine
10. dry with materialdried over Na2SO4
11. filtrationfiltered
12. concentrationThe organics were concentrated under reduced pressure at 60° C

ORD record

ord-c6694b0b144945b69c01a79189e58383

Source dataset

uspto-grants-2014_11

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08883782B2