反応 #157872

反応方程式

tert-Butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole-1-carboxylate

tri(2-furyl)phosphine

cesium carbonate

(5R)-5-[(E)-2-(5-bromo-6-methoxypyridin-2-yl)-2-(4-chlorophenyl)ethenyl]-1-(2,4-dimethoxybenzyl)pyrrolidin-2-one

→

(5R)-5-{(E)-2-(4-chlorophenyl)-2-[6-methoxy-5-(1H-pyrazol-4-yl)pyridin-2-yl]ethenyl}-1-(2,4-dimethoxybenzyl)pyrrolidin-2-one

収率 63.0%

溶媒

1,4-dioxane

ethyl acetate

water

反応条件

後処理

1. 1
   workup.WAITThe reaction solution was left
2. 2
   温度to cool
3. 3
   ろ過filtered through celite
4. 4
   洗浄The filtrate was washed with brine
5. 5
   乾燥dried over sodium sulfate
6. 6
   ろ過After filtration
7. 7
   その他the solvent was evaporated under reduced pressure
8. 8
   その他The residue was purified by silica gel column chromatography (hexane:ethyl acetate=9:1→7:3)

実験手順

tert-Butyl 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole-1-carboxylate (216 mg), tris(dibenzylideneacetone)dipalladium(0) (33.7 mg), tri(2-furyl)phosphine (51.5 mg) and cesium carbonate (239 mg) were added to a solution of (5R)-5-[(E)-2-(5-bromo-6-methoxypyridin-2-yl)-2-(4-chlorophenyl)ethenyl]-1-(2,4-dimethoxybenzyl)pyrrolidin-2-one obtained in Reference Example 4-43 (200 mg) in 1,4-dioxane (3 mL)-water (1 mL), and the mixture was stirred at an external temperature for 80° C. for three hours. The reaction solution was left to cool, diluted with ethyl acetate and filtered through celite. The filtrate was washed with brine and dried over sodium sulfate. After filtration, the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=9:1→7:3) to give (5R)-5-{(E)-2-(4-chlorophenyl)-2-[6-methoxy-5-(1H-pyrazol-4-yl)pyridin-2-yl]ethenyl}-1-(2,4-dimethoxybenzyl)pyrrolidin-2-one as a colorless oil (125 mg, 63%).

出典