反应详情

温度

0 °C

A round bottom flask equipped with a stir bar and rubber septum was charged with 5-[4-(1-hydroxy-ethyl)-4-methylpyrrolidin-3-yl)-2-methoxyphenol (2.4 g, 9.55 mmol), dry CH2Cl2 (50 mls), and DIEA (3.49 mls, 20.1 mmol) under a nitrogen atmosphere. The mixture was chilled to 0° C. and (S)-2.2-dimethyl-[1,3]dioxolane-4-carbonyl chloride (3.14 g, 19.1 mmol) in 15 ml of CH2Cl2 was added dropwise by syringe. The reaction mixture was allowed to gradually warm to room temperature over a 16-hour period. The mixture then was diluted with 50 ml of CH2Cl2, washed with 1N HCl (2×50 ml), saturated aqueous NaHCO3 (1×50 ml), dried over Na2SO4, and concentrated to 3.9 g of a tan foam. The material was taken up in 100 ml CH3OH and chilled to 0° C. Three equivalents of aqueous 1N LiOH then were added (29 ml, 29.0 mmol), the mixture was stirred at 0° C. for 2 hours, then warmed to room temperature for 2 hours. The reaction mixture next was concentrated under reduced pressure with the bath temperature at 30° C. to remove CH3OH. The remaining aqueous material was neutralized with saturated NH4Cl to pH 7 and extracted with EtOAc (2×100 ml). The extracts were dried over Na2SO4 and concentrated to 2.74 g of a tan foam (76%).

1. customA round bottom flask equipped with a stir bar
2. temperatureto gradually warm to room temperature over a 16-hour period
3. washwashed with 1N HCl (2×50 ml), saturated aqueous NaHCO3 (1×50 ml)
4. dry with materialdried over Na2SO4
5. concentrationconcentrated to 3.9 g of a tan foam
6. temperaturechilled to 0° C
7. additionThree equivalents of aqueous 1N LiOH then were added (29 ml, 29.0 mmol)
8. temperaturewarmed to room temperature for 2 hours
9. concentrationThe reaction mixture next was concentrated under reduced pressure with the bath temperature at 30° C.
10. customto remove CH3OH
11. extractionextracted with EtOAc (2×100 ml)
12. dry with materialThe extracts were dried over Na2SO4
13. concentrationconcentrated to 2.74 g of a tan foam (76%)