Lithium diisopropylamide → 1,1,1-Trifluoro-4-(5-fluoro-2-methoxyphenyl)-2-furo[3,2-c]pyridin-2-ylmethyl-4-methylpentan-2-ol

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Reaktionsschritte

A solution of 2-methylfuro[3,2-c]pyridine (prepared according to the procedure by T. Kitamura, K. Tsuda, and Y. Fujiwara, Tetrahedron Lett. 1998, 39, pp. 5375-5376) (26.0 mg, 0.195 mmol) in 2 mL of THF was treated with lithium diisopropylamide (LDA; 1.5 M in cyclohexane, 195 μL) dropwise at −78° C. The mixture was stirred for 30 minutes (the color changed from yellow to orange-red) and was slowly treated with a solution of 1,1,1-trifluoro-4-(5-fluoro-2-methoxyphenyl)-4-methylpentan-2-one (81.5 mg, 0.293 mmol) in 1 mL of THF. The reaction was stirred at −78° C. for 4.5 hours, quenched with 5 mL of saturated ammonium chloride solution, and diluted with 20 mL of ethyl acetate. The phases were separated and the aqueous layer was extracted with three 10 mL portions of ethyl acetate. The combined organic layers were washed with brine, dried over magnesium sulfate, and concentrated in vacuo. Flash chromatography (ethyl acetate-hexanes, 5% to 50% gradient) gave 36.0 mg (45% yield) of the title product as a clear oil.

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