Tetrahydrofuran → HCID 67241884, compound

Participants

Reaction Conditions

Reaction Steps

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.

Provenance & Evidence