2-Ketobutyric acid methyl ester → Methyl 2-(2-fluoro-3-methyl-4-pyridinyl)-2-hydroxybutanoate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

6.9 ml (11 mmol) of 1.6M butyllithium in hexane are added dropwise to a solution, stirred at −78° C. of 2.6 g (11 mmol) of 2-fluoro-4-iodo-3-methylpyridine (described in J.O.C., 1993, 58, pp. 7832) in 100 ml of THF. The reaction mixture is then stirred for 10 minutes at −78° C. before the addition of a solution of 1.5 g (12.9 mmol) of methyl 2-oxo-butyrate in 20 ml of THF. The reaction mixture is stirred for 10 minutes at −78° C., and then hydrolysed with a mixture of water/THF. The aqueous phase is decanted and then extracted 3 times with 50 ml of methyl acetate each time. The combined organic phases are dried, concentrated and purified by chromatography over silica (eluant dichloromethane/acetone 95/5) to yield the expected product.

Herkunft & Nachweise