Imidazole → (4-Bromo-phenoxy)-triisopropylsilane

HRID 1811512Notes

Reaction equation

HRID 1811512 reaction equation
[Br:1][C:2]1[CH:7]=[CH:6][C:5]([OH:8])=[CH:4][CH:3]=1.N1C=CN=C1.[CH:14]([Si:17](Cl)([CH:21]([CH3:23])[CH3:22])[CH:18]([CH3:20])[CH3:19])([CH3:16])[CH3:15].[NH4+].[Cl-]>ClCCCl>[Br:1][C:2]1[CH:7]=[CH:6][C:5]([O:8][Si:17]([CH:21]([CH3:23])[CH3:22])([CH:18]([CH3:20])[CH3:19])[CH:14]([CH3:16])[CH3:15])=[CH:4][CH:3]=1

Participants

6

Reactant 4

HCID 795ImidazoleHCID 78084-BromophenolHCID 25517Ammonium ChlorideHCID 139400Triisopropylsilyl chloride

Product 1

HCID 536194(4-Bromo-phenoxy)-triisopropylsilaneYield 110.2%

Reagents, catalysts & solvents 1

HCID 111,2-DichloroethaneSolvent

Procedure

To a stirred solution of 4-bromophenol (25.1 g, 146 mmol), and imidazole (19.9 g, 292 mmol) in 1,2-dichloroethane (150 mL) at 23° C. was added triisopropylsilylchloride (34.4 mL, 161 mmol). The mixture was stirred for 12 h and poured onto saturated aqueous NH4Cl (400 mL), followed by extraction with CH2Cl2 (3×200 mL). The combined extracts were washed with brine (300 mL), dried (Na2SO4), and concentrated in vacuo to give a pale yellow oil which was crude oil was purified via short-path distillation (0.5 mmHg, 130° C.) to yield (4-Bromo-phenoxy)-triisopropylsilane as a colorless oil (53.0 g, 99% yield). Rf 0.81 (3:1 hexanes/EtOAc) IR (thin film) 2945, 2892, 2867 cm−1. 1H NMR (300 MHz, CDCl3) δ 7.30 (2H, d, J=9 Hz), 6.75 (2H, d, J=9 Hz), 1.29-1.18 (3H, m), 1.08 (18H, d, J=7 Hz). 13C NMR (75 MHz, CDCl3) δ 155.0, 132.0, 121.5, 112.9, 17.6, 12.4. HRMS calcd. for C15H26OSiBr (MH+) 329.0936, found 329.0937.

Workup

  1. extractionfollowed by extraction with CH2Cl2 (3×200 mL)
  2. washThe combined extracts were washed with brine (300 mL)
  3. dry with materialdried (Na2SO4)
  4. concentrationconcentrated in vacuo
  5. customto give a pale yellow oil which
  6. distillationwas purified via short-path distillation (0.5 mmHg, 130° C.)

Sources & evidence

ORD record
ord-a5fedb4d1e8948028f9b07dbd7c80420
Source dataset
uspto-grants-2013_01
Patent number
US08362283B2

Reaction notes

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