Imidazole → 4-Tert-butyl(dimethyl)silyloxymethyl-3-methylbenzofuran-2-carboxylic acid ethyl ester

HRID 29329Notes

Reaction equation

HRID 29329 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[O:7][C:8]2[CH:15]=[CH:14][CH:13]=[C:12]([CH2:16][OH:17])[C:9]=2[C:10]=1[CH3:11])=[O:5])[CH3:2].[Si:18](Cl)([C:21]([CH3:24])([CH3:23])[CH3:22])([CH3:20])[CH3:19].N1C=CN=C1>CN(C=O)C.O>[CH2:1]([O:3][C:4]([C:6]1[O:7][C:8]2[CH:15]=[CH:14][CH:13]=[C:12]([CH2:16][O:17][Si:18]([C:21]([CH3:24])([CH3:23])[CH3:22])([CH3:20])[CH3:19])[C:9]=2[C:10]=1[CH3:11])=[O:5])[CH3:2]

Participants

6

Reactant 3

HCID 795ImidazoleHCID 28928tert-Butyldimethylsilyl chlorideHCID 687118924-Hydroxymethyl-3-methylbenzofuran-2-carboxylic acid ethyl ester

Product 1

HCID 687119864-Tert-butyl(dimethyl)silyloxymethyl-3-methylbenzofuran-2-carboxylic acid ethyl esterYield 96.2%

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Procedure

To a solution of 0.220 g (0.940 mmol) of 4-hydroxymethyl-3-methylbenzofuran-2-carboxylic acid ethyl ester in 5 mL of DMF was added 0.156 g (1.034 mmol) of t-butyldimethylsilyl chloride and 0.160 g (2.350 mmol) of imidazole and the reaction was stirred at room temperature for 14 h. The reaction mixture was diluted with water and extracted with ether. The combined organics were washed with water and brine, dried over magnesium sulfate, filtered and concentrated in vacuo. The residue was chromatographed on silica gel eluting with ethyl acetate/hexanes (1:10) to provide 0.315 g of 4-tert-butyl(dimethyl)silyloxymethyl-3-methylbenzofuran-2-carboxylic acid ethyl ester.

Workup

  1. extractionextracted with ether
  2. washThe combined organics were washed with water and brine
  3. dry with materialdried over magnesium sulfate
  4. filtrationfiltered
  5. concentrationconcentrated in vacuo
  6. customThe residue was chromatographed on silica gel eluting with ethyl acetate/hexanes (1:10)

Sources & evidence

ORD record
ord-cb363f79099b48a4868058b02aaf82d2
Source dataset
uspto-grants-2008_09
Patent number
US07420001B2

Reaction notes

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