反应详情

温度

-78 °C

To a solution of 2-bromo-5-(methoxymethyl)thiophene (439 mg, 2.12 mmol) in 6 mL of 9:1 tetrahydrofuran/hexamethylphosphoramide under argon at −78° C. was added n-butyllithium (0.93 mL, 2.5 M in hexanes) dropwise. After stirring for 2 minutes at −78° C., dimethylformamide (0.82 mL, 10.6 mmol) was added in a single portion and the reaction mixture was allowed to warm to room temperature before being poured into 30 mL of 1 N hydrochloric acid. Organics were extracted with 1:1 ether/hexanes (3×30 mL), washed with water (2×30 mL, brine (30 mL), dried over magnesium sulfate, filtered and concentrated. The crude residue was subjected to chromatography on silica gel with gradient elution (5-20% ethyl acetate in hexanes) to give 5-(methoxymethyl)thiophene-2-carbaldehyde (103 mg, 31%) as an oil. Used without further characterization.

1. temperatureto warm to room temperature
2. extractionOrganics were extracted with 1:1 ether/hexanes (3×30 mL)
3. washwashed with water (2×30 mL, brine (30 mL)
4. dry with materialdried over magnesium sulfate
5. filtrationfiltered
6. concentrationconcentrated
7. washThe crude residue was subjected to chromatography on silica gel with gradient elution (5-20% ethyl acetate in hexanes)