Water → N-(3-(3-(1,3-dioxolan-2-yl)phenyl)-3-hydroxy-2,2,6,7-tetramethyl-2,3-dihydro-1-benzofuran-5-yl)-3,3-dimethylbutanamide

HRID 2376548Notes

Reaction equation

HRID 2376548 reaction equation
Br[C:2]1[CH:3]=[C:4]([CH:8]2[O:12][CH2:11][CH2:10][O:9]2)[CH:5]=[CH:6][CH:7]=1.C([Li])CCC.[CH3:18][C:19]([CH3:39])([CH3:38])[CH2:20][C:21]([NH:23][C:24]1[C:25]([CH3:37])=[C:26]([CH3:36])[C:27]2[O:31][C:30]([CH3:33])([CH3:32])[C:29](=[O:34])[C:28]=2[CH:35]=1)=[O:22].O>C1COCC1>[O:9]1[CH2:10][CH2:11][O:12][CH:8]1[C:4]1[CH:3]=[C:2]([C:29]2([OH:34])[C:28]3[CH:35]=[C:24]([NH:23][C:21](=[O:22])[CH2:20][C:19]([CH3:18])([CH3:38])[CH3:39])[C:25]([CH3:37])=[C:26]([CH3:36])[C:27]=3[O:31][C:30]2([CH3:33])[CH3:32])[CH:7]=[CH:6][CH:5]=1

Participants

6

Reactant 4

HCID 962WaterHCID 873062-(3-Bromophenyl)-1,3-dioxolaneHCID 231138583,3-dimethyl-N-(2,2,6,7-tetramethyl-3-oxo-2,3-dihydro-1-benzofuran-5-yl)butanamideHCID 178418339Butyllithium

Product 1

HCID 23114094N-(3-(3-(1,3-dioxolan-2-yl)phenyl)-3-hydroxy-2,2,6,7-tetramethyl-2,3-dihydro-1-benzofuran-5-yl)-3,3-dimethylbutanamideYield 92.2%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To a solution of 2-(3-bromophenyl)-1,3-dioxolane (1.65 mL, 10.9 mmol) in THF (20 mL) was added dropwise at −78° C. under an argon atmosphere n-butyllithium (1.59 M hexane solution, 6.4 mL, 10.2 mmol), and the resulting mixture was stirred for 30 minutes. To the reaction solution was added dropwise at −78° C. a solution of 3,3-dimethyl-N-(2,2,6,7-tetramethyl-3-oxo-2,3-dihydro-1-benzofuran-5-yl)butanamide (1.0 g, 3.30 mmol) obtained in Reference Example 65 in THF (10 mL), and the resulting mixture was stirred for 30 minutes. The reaction solution was warmed to room temperature and stirred for 1 hour, and water was added to the reaction solution and the product was extracted with ethyl acetate. The organic layer was washed with water and saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The obtained residue was purified by silica gel column chromatography (ethyl acetate:hexane=2:3) to obtain 1.38 g (yield: 92%) of N-(3-(3-(1,3-dioxolan-2-yl)phenyl)-3-hydroxy-2,2,6,7-tetramethyl-2,3-dihydro-1-benzofuran-5-yl)-3,3-dimethylbutanamide as an amorphous powder. To a mixed solution of the obtained N-(3-(3-(1,3-dioxolan-2-yl)phenyl)-3-hydroxy-2,2,6,7-tetramethyl-2,3-dihydro-1-benzofuran-5-yl)-3,3-dimethylbutanamide (300 mg, 0.66 mmol) in acetone (4 mL)-water (0.3 mL) was added pyridinium p-toluenesulfonate (5 mg, 0.03 mmol), and the mixture was stirred for 30 minutes. The reaction solution was cooled to room temperature, and water was added to the reaction solution and the product was extracted with ethyl acetate. The organic layer was washed with water and saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The obtained residue was recrystallized from THF-diisopropyl ether to obtain 194 mg (yield: 72%) of the title compound. Melting point: 189-190° C.

Workup

  1. stirringthe resulting mixture was stirred for 30 minutes
  2. stirringstirred for 1 hour
  3. extractionthe product was extracted with ethyl acetate
  4. washThe organic layer was washed with water and saturated brine
  5. dry with materialdried over anhydrous sodium sulfate
  6. concentrationconcentrated under reduced pressure
  7. customThe obtained residue was purified by silica gel column chromatography (ethyl acetate:hexane=2:3)

Sources & evidence

ORD record
ord-db30fb673ffa4f009b93f8c93db5d781
Source dataset
uspto-grants-2008_12
Patent number
US07465815B2

Reaction notes

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