Imidazole → 2-Chloroethyl 3-t-butyldimethylsilyloxybenzoate

HRID 52760Notes

Reaction equation

HRID 52760 reaction equation
[OH:1][C:2]1[CH:3]=[C:4]([CH:11]=[CH:12][CH:13]=1)[C:5]([O:7][CH2:8][CH2:9][Cl:10])=[O:6].[Si:14](Cl)([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:16])[CH3:15].N1C=CN=C1.C(OCC)(=O)C.CCCCCC>CN(C=O)C.O>[Cl:10][CH2:9][CH2:8][O:7][C:5](=[O:6])[C:4]1[CH:11]=[CH:12][CH:13]=[C:2]([O:1][Si:14]([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:16])[CH3:15])[CH:3]=1

Participants

7

Reactant 4

HCID 795ImidazoleHCID 28928tert-Butyldimethylsilyl chlorideHCID 151587912-Chloroethyl 3-hydroxybenzoateHCID 21226206Ethyl acetate hexane

Product 1

HCID 151587922-Chloroethyl 3-t-butyldimethylsilyloxybenzoate

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 6228DimethylformamideSolvent

Procedure

To a solution of 2-chloroethyl 3-hydroxybenzoate (4.0 g, 0.02 mol) and tert-butyldimethylsilyl chloride (4.5 g, 0.029 mol) in 5 mL of dry DMF was gradually added imidazole (92.7 g, 0.04 mol). The solution was then stirred overnight. TLC analysis (silica gel, 20% ethyl acetate/hexane) showed clean conversion to a new material. The solution was poured into a 25 mL of water and extracted with 3×25 mL of ether. The combined ether solutions were dried over anhydrous MgSO4. Evaporation of the solvent gave an oil which was chromatographed on silica using 10% ethyl acetate/hexane to give the product quantitatively as a colorless liquid: 1H NMR (CDCl3) δ 0.218 (s, 6H), 0.994 (s, 9H), 3.81 (t, 2H, J=5.7 MHz), 4.56 (t, 2H, J=5.7 MHz), 7.05-7.65 (m, 4H); 13C NMR (CDCl3) δ -4.97, 17.66, 25.12, 41.06, 63.91,120.61,122.19, 124.60, 128.95, 130.53, 155.31, 165.35; MS m/e (rel intensity) 314 (14), 257 (9), 235 (9), 213 (100), 185 (6), 149 (7), 135 (10), 120 (6), 93 (13), 83 (6), 69 (9), 55 (9); Exact found 314.1110. ##STR29##

Workup

  1. extractionextracted with 3×25 mL of ether
  2. dry with materialThe combined ether solutions were dried over anhydrous MgSO4
  3. customEvaporation of the solvent
  4. customgave an oil which
  5. customwas chromatographed on silica using 10% ethyl acetate/hexane
  6. customto give the product quantitatively as a colorless liquid

Sources & evidence

ORD record
ord-d8541ba3421940b494fc781821384960
Source dataset
uspto-grants-1997_04
Patent number
US05616729

Reaction notes

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