Dichloromethane → HCID 16037701, compound

In a flame-dried flask filled with argon, the silyl ether 8-[dimethyl-1,1,2-trimethyl-propyl)-silanyloxy]-7-[(3R)-3-hydroxy-3-phenyl-propyl]-2,3-dimethyl-imidazo[1,2-a]pyridine-6-carboxylic acid dimethylamide (2.10 g, 4.1 mmol, sample contained 6 mol-% of the (3S)-enantiomer) was dissolved in dry THF (30 ml). At room temperature, a solution of tetrabutylammonium fluoride in THF (1 M, 420 ml, 4.2 mmol) was added slowly. A brown solution was obtained, which was stirred for 5 hours at room temperature. The reaction mixture was poured onto a mixture of saturated ammonium chloride solution (30 ml) and dichloromethane (50 ml). The phases were separated and the aqueous phase was extracted with dichloromethane (3×15 ml). The combined organic phases were washed with water (20 ml), dried over sodium sulfate, and concentrated under reduced pressure. A grey solid (2.6 g) remained which was treated with a mixture of acetone (I ml) and diethyl ether (10 ml). The suspension was filtered, the residue was washed with diethyl ether and dried in vacuo. This afforded 1.6 g of the title compound still containing traces of impurities. After crystallization from ethyl acetate (100 ml) and isopropanol (10 ml), the spectroscopically pure title compound (1.3 g, 86% yield) was obtained as a grey crystalline solid. The optical purity was confirmed by capillary electrophoresis (85.2% ee).

1. additionIn a flame-dried flask filled with argon
2. customA brown solution was obtained
3. customThe phases were separated
4. extractionthe aqueous phase was extracted with dichloromethane (3×15 ml)
5. washThe combined organic phases were washed with water (20 ml)
6. dry with materialdried over sodium sulfate
7. concentrationconcentrated under reduced pressure
8. additionwas treated with a mixture of acetone (I ml) and diethyl ether (10 ml)
9. filtrationThe suspension was filtered
10. washthe residue was washed with diethyl ether
11. customdried in vacuo
12. customAfter crystallization from ethyl acetate (100 ml) and isopropanol (10 ml)

ORD record

ord-f484bda4f182497c942c40244d754357

Source dataset

uspto-grants-2008_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07326784B2