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

Participants

Reaction Conditions

Reaction Steps

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 a-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.

Provenance & Evidence