1,1-Dibromoethane → 1-Trityl-4-(4-cyanobenzyl)imidazole

HRID 443302Notes

Reaction equation

HRID 443302 reaction equation
BrC(Br)C.Br[CH2:6][C:7]1[CH:12]=[CH:11][C:10]([C:13]#[N:14])=[CH:9][CH:8]=1.I[C:16]1[N:17]=[CH:18][N:19]([C:21]([C:34]2[CH:39]=[CH:38][CH:37]=[CH:36][CH:35]=2)([C:28]2[CH:33]=[CH:32][CH:31]=[CH:30][CH:29]=2)[C:22]2[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=2)[CH:20]=1>C1COCC1.[Zn].[Ni].C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1>[C:21]([N:19]1[CH:20]=[C:16]([CH2:6][C:7]2[CH:12]=[CH:11][C:10]([C:13]#[N:14])=[CH:9][CH:8]=2)[N:17]=[CH:18]1)([C:28]1[CH:29]=[CH:30][CH:31]=[CH:32][CH:33]=1)([C:34]1[CH:39]=[CH:38][CH:37]=[CH:36][CH:35]=1)[C:22]1[CH:27]=[CH:26][CH:25]=[CH:24][CH:23]=1

Participants

7

Reactant 3

HCID 112011,1-DibromoethaneHCID 869964-(Bromomethyl)benzonitrileHCID 6182524-Iodo-1-tritylimidazole

Product 1

HCID 158375331-Trityl-4-(4-cyanobenzyl)imidazole

Reagents, catalysts & solvents 3

HCID 23994ZincCatalystHCID 57357981bis(triphenylphosphine) NickelCatalystHCID 8028TetrahydrofuranSolvent2×

Conditions

Temperature
20 °C

Procedure

To a suspension of activated zinc dust (3.57 g, 54.98 mmol) in THF (50 mL) was added dibromoethane (0.315 mL, 3.60 mmol) and the reaction stirred under argon for 45 minutes, at 20° C. The suspension was cooled to 0° C. and α-bromo-p-tolunitrile (9.33 g, 47.6 mmol) in THF (100 mL) was added dropwise over a period of 10 minutes. The reaction was then allowed to stir at 20° C. for 6 hours and bis(triphenylphosphine) Nickel II chloride (2.40 g, 3.64 mmol) and 4-iodo-1-tritylimidazole (15.95 g, 36.6 mmol, S. V. Ley, et al., J. Org. Chem. 56, 5739 (1991)) were added in one portion. The resulting mixture was stirred 16 hours at 20° C. and then quenched by addition of saturated NH4Cl solution (100 mL) and the mixture stirred for 2 hours. Saturated aq. NaHCO3 solution was added to give a pH of 8 and the solution was extracted with EtOAc (2×250 mL), dried (MgSO4) and the solvent evaporated in vacuo. The residue was chromatographed (Silica gel, 0-20% EtOAc in CH2Cl2) to afford the title compound as a white solid.

Workup

  1. temperatureThe suspension was cooled to 0° C.
  2. stirringto stir at 20° C. for 6 hours
  3. stirringThe resulting mixture was stirred 16 hours at 20° C.
  4. customquenched by addition of saturated NH4Cl solution (100 mL)
  5. stirringthe mixture stirred for 2 hours
  6. additionSaturated aq. NaHCO3 solution was added
  7. customto give a pH of 8
  8. extractionthe solution was extracted with EtOAc (2×250 mL)
  9. dry with materialdried (MgSO4)
  10. customthe solvent evaporated in vacuo
  11. customThe residue was chromatographed (Silica gel, 0-20% EtOAc in CH2Cl2)

Sources & evidence

ORD record
ord-b785ab5f372e4112b3ba055991d9440a
Source dataset
uspto-grants-1999_04
Patent number
US05891889

Reaction notes

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