反应详情

A solution of 4.44 g (30 mmol) of 3,5-dichloropyridine in 40 mL of THF is added dropwise over 30 minutes to a stirred solution of 23 mL (35 mmol) of 1.5 M LDA in 30 mL THF at −78° C. After a further 15 minutes at −78° C., a solution of 6.13 g (42 mmol) of diethyl oxalate in 15 mL THF is added, and the temperature is allowed to rise slowly to −20° C. The reaction mixture is then quenched with aqueous ammonium chloride, the solvent is removed, and the residue is worked up in EtOAc. Chromatography on silica, eluting with hexane/EtOAc (9:1), gives 2.4 g (32%) of the title compound as an oil.

1. customto rise slowly to −20° C
2. customThe reaction mixture is then quenched with aqueous ammonium chloride
3. customthe solvent is removed
4. washChromatography on silica, eluting with hexane/EtOAc (9:1)