5-Bromo-2-methoxypyridine → (6-Methoxypyridin-3-yl)(thiazol-5-yl)methanone

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A n-BuLi solution (1.89 mL, 3.03 mmol, 1.6 M solution in hexane) was slowly added to a −78° C. solution of 5-bromo-2-methoxypyridine (0.392 mL, 3.03 mmol) in dry THF (10 mL). After addition, stirring was continued for an additional 40 minutes and N-methoxy-N-methylthiazole-5-carboxamide (0.600 g, 3.48 mmol, Intermediate 11: step a) dissolved in THF (10 mL) was slowly added. The mixture was stirred at −78° C. for 10 minutes then warmed to 0° C. and stirred for 1 hour. The cold solution was quenched with saturated aqueous NH4Cl and warmed to room temperature. H2O was added and layers were separated. The aqueous layer was extracted with EtOAc (3×) and the combined organic extracts washed with brine, dried (Na2SO4), filtered, evaporated in vacuo, preabsorbed onto silica gel and chromatographed (CH2Cl2/EtOAc) to provide product. The pure white solid title compound was precipitated from MeOH, filtered and dried under reduced pressure.

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