Reaktion #157872

Reaktionsgleichung

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

Ausbeute 63.0%

Lösungsmittel

1,4-dioxane

ethyl acetate

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.WAITThe reaction solution was left
2. 2
   Temperaturto cool
3. 3
   Filtrationfiltered through celite
4. 4
   WaschenThe filtrate was washed with brine
5. 5
   Trocknendried over sodium sulfate
6. 6
   FiltrationAfter filtration
7. 7
   Sonstigethe solvent was evaporated under reduced pressure
8. 8
   SonstigeThe residue was purified by silica gel column chromatography (hexane:ethyl acetate=9:1→7:3)

Vorschrift

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%).

Quelle