Imidazole → Ethyl 4-((tert-butyldimethylsilyl)oxy)cyclohexanecarboxylate
Reaction equation
[CH2:1]([O:3][C:4]([CH:6]1[CH2:11][CH2:10][CH:9]([OH:12])[CH2:8][CH2:7]1)=[O:5])[CH3:2].N1C=CN=C1.[C:18]([Si:22]([CH3:25])([CH3:24])Cl)([CH3:21])([CH3:20])[CH3:19]>C1COCC1.CN(C1C=CN=CC=1)C.C(OCC)(=O)C.[Cl-].[NH4+]>[CH2:1]([O:3][C:4]([CH:6]1[CH2:11][CH2:10][CH:9]([O:12][Si:22]([C:18]([CH3:21])([CH3:20])[CH3:19])([CH3:25])[CH3:24])[CH2:8][CH2:7]1)=[O:5])[CH3:2]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 4
Procedure
To a solution of 4-hydroxycyclohexanecarboxylic acid ethyl ester as a mixture of cis and trans isomers (8.7 g, 50.51 mmol) in THF (300 mL) at 0° C. was added imidazole (4.8 g, 70.72 mmol), DMAP (20 mol %, 1.23 g, 10.10 mmol,) and tert-butyl dimethylchlorosilane (9.1 g, 60.61 mmol). The reaction mixture was warmed to room temperature, stirred overnight, and diluted with ethyl acetate and saturated aqueous ammonium chloride. The aqueous layer was extracted with ethyl acetate and the combined organic layers were washed with brine and dried over sodium sulfate. Solvent was removed and the crude oil was filtered through silica gel and solvent removed to give 4-(tert-butyldimethylsilanyloxy)cyclohexanecarboxylic acid ethyl ester (11.1 g, 77%) as a mixture of diastereomers.
Workup
- extractionThe aqueous layer was extracted with ethyl acetate
- washthe combined organic layers were washed with brine
- dry with materialdried over sodium sulfate
- customSolvent was removed
- filtrationthe crude oil was filtered through silica gel and solvent
- customremoved
Sources & evidence
- ORD record
- ord-37299a2a26554ea9bbfc1f897eb32a0c
- Source dataset
- uspto-grants-2014_03
- Patent number
- US08664242B2
Reaction notes
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