Cesium carbonate → [4-Difluoromethoxy-2-ethyl-8-fluoro-3-(4-thiazol-2-ylbenzyl)quinolin-5-yloxy]acetic acid

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Reaction Conditions

Reaction Steps

A mixture of {4-difluoromethoxy-2-ethyl-8-fluoro-3-[4-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)benzyl]quinolin-5-yloxy}acetic acid methyl ester (0.052 g), 2-bromothiazole (0.076 g), [1,1′-bis(diphenylphosphino)ferrocene]dichloropalladium (0.060 g), 1,4-dioxane (2.0 mL) and 2.0M aqueous cesium carbonate solution (0.19 mL) was heated at 90° C. overnight. The mixture was cooled to room temperature, diluted with ethyl acetate and filtered. The filtrate was concentrated under reduced pressure, and the residue dissolved in tetrahydrofuran (5.0 mL) and 1.0M aqueous lithium hydroxide solution (0.19 mL), and the resulting mixture was stirred at room temperature for 1 hour. The mixture was concentrate to low bulk under reduced pressure, and the residue acidified by the addition 0.1M aqueous hydrochloric acid solution and then extracted with ethyl acetate. The combined extracts were dried over magnesium sulfate and then concentrated under reduced pressure. Purification of the residue by column chromatography on C-18 column gave title compound (0.020 g).

Provenance & Evidence