Reaction equation
Br[Zn][CH2:3][C:4]([O:6][CH2:7][CH3:8])=[O:5].[CH3:9][C:10]1[C:11](=[O:18])[CH:12]=[C:13]([CH3:17])[C:14](=[O:16])[CH:15]=1.Cl.C(OCC)(=O)C>C1COCC1>[CH2:7]([O:6][C:4](=[O:5])[CH2:3][C:11]1([OH:18])[CH:12]=[C:13]([CH3:17])[C:14](=[O:16])[CH:15]=[C:10]1[CH3:9])[CH3:8]Participants
Procedure
Under nitrogen atmosphere, 6 mL of THF was added to 1.22 g (2 mmol, 0.6 equivalent) of (BrZnCH2COOEt.THF)2. Under argon atmosphere, a solution of 0.45 g (3.33 mmol) of 2,5-dimethyl-p-benzoquinone in 3 mL of THF was added dropwise while stirring at. 0˜5° C. The mixture was stirred at 20˜25° C. for 1 hour. 5 mL of 1N hydrochloric acid was added dropwise at 20° C. or lower, followed by dilution with 25 mL of ethyl acetate. Then, the layers were separated. The organic layer was washed successively with 5 mL (×2) of 1N hydrochloric acid, 5 mL of water, 5 mL (×2) of an aqueous saturated sodium bicarbonate solution, and 5 mL (×2) of an aqueous saturated sodium chloride solution. After washing, the organic layer was dried with anhydrous magnesium sulfate. After concentration under reduced pressure, purification with silica gel column (developing solvent; ethyl acetate/n-hexane=1/3, 1/2) afforded 0.65 g of the desired product (yield 87%).
Workup
- custom0˜5° C
- stirringThe mixture was stirred at 20˜25° C. for 1 hour
- customThen, the layers were separated
- washThe organic layer was washed successively with 5 mL (×2) of 1N hydrochloric acid, 5 mL of water, 5 mL (×2) of an aqueous saturated sodium bicarbonate solution, and 5 mL (×2) of an aqueous saturated sodium chloride solution
- washAfter washing
- dry with materialthe organic layer was dried with anhydrous magnesium sulfate
- concentrationAfter concentration
- customunder reduced pressure, purification with silica gel column (developing solvent; ethyl acetate/n-hexane=1/3, 1/2)
Sources & evidence
- ORD record
- ord-f87be05672364ef188fcf18f3e2c376b
- Source dataset
- uspto-grants-2012_01
- Patent number
- US08093403B2
Linked notes
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