Diethyl Oxalate → HCID 66633701, compound

Participants

Reaction Steps

Under argon, lithium bis(trimethylsilyl)amide (21 ml, 1 M/L in tetrahydrofuran) was initially charged in tetrahydrofuran (150 ml). At −78° C., 1-[2-(5-fluoropyridin-3-yl)-4-methyl-1,3-thiazol-5-yl]ethanone (5.0 g, 21 mmol, prepared analogously to Biorg. & Med. Chem. Lett 1056 (2007) and 2828 (2010)) dissolved in diethyl ether was slowly added dropwise and the reaction mixture was stirred for 2 h. Diethyl oxalate (3.1 g, 21 mmol) dissolved in ether was added dropwise and the reaction mixture was stirred at room temperature for 16 h. Subsequently, potassium hydrogensulphate solution (5%) was added and the mixture was extracted repeatedly with ethyl acetate. The combined organic phases were dried and the solvent was removed under reduced pressure. This gave 7.1 g (99% of theory) of ethyl 4-[2-(5-fluoropyridin-3-yl)-4-methyl-1,3-thiazol-5-yl]-2,4-dioxobutanoate.

Provenance & Evidence