反応 #74652

反応方程式

4-chloro-2-iodophenol

tert-butyl 4-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2-yl)piperazine-1-carboxylate

sodium carbonate

1,4-dioxane

ammonium chloride

→

product

tert-Butyl 4-(4-(5-chloro-2-hydroxyphenyl)pyridin-2-yl)piperazine-1-carboxylate

溶媒

water

water

反応条件

後処理

1. 1
   その他was sparged 5 minutes with argon
2. 2
   その他the vial was capped
3. 3
   温度the reaction mixture was cooled to ambient temperature
4. 4
   抽出the mixture was extracted with ethyl acetate (3×)
5. 5
   洗浄The combined organic layers were washed with brine
6. 6
   乾燥dried over sodium sulfate
7. 7
   ろ過filtered
8. 8
   濃縮concentrated onto diatomaceous earth
9. 9
   その他The residue was purified by automated flash chromatography (24 g SiO2, hexanes to ethyl acetate)

実験手順

A mixture of 4-chloro-2-iodophenol (367 mg, 1.44 mmol), tert-butyl 4-(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)pyridin-2-yl)piperazine-1-carboxylate (707.5 mg, 1.817 mmol), and sodium carbonate (615.0 mg, 5.802 mmol) in 1,4-dioxane (6.0 mL, 77 mmol) and water (2.0 mL, 110 mmol) was sparged 5 minutes with argon. Tetrakis(triphenylphosphine)palladium(0) (100.0 mg, 0.08654 mmol) was added, the vial was capped, and the reaction mixture was heated at 90° C. After 4 hours, the reaction mixture was cooled to ambient temperature and poured into water. Saturated aqueous ammonium chloride was added, and the mixture was extracted with ethyl acetate (3×). The combined organic layers were washed with brine, dried over sodium sulfate, filtered, and concentrated onto diatomaceous earth. The residue was purified by automated flash chromatography (24 g SiO2, hexanes to ethyl acetate) to afford the product as an amber oil that solidified on standing (491 mg, 74%).

出典