2-Butene, 1-bromo-3-methyl- → [1-(3-methyl-but-2-enyl)-1H-benzoimidazol-2-yl]-methanol

Participants

Reaction Steps

To a solution of (1H-benzoimidazol-2-yl)-methanol (457 mg, 3.09 mmol) and 4-bromo-2-methyl-2-butene (0.36 mL, 3.09 mmol) in DMF (10 mL) was added DIPEA (0.69 mL, 3.70 mmol) at 60° C. overnight and in the morning, the mixture was cooled and concentrated. The residue was dissolved in saturated NaHCO3 (20 mL) and extracted with CH2Cl2 (3×30 mL). The combined organic layers were dried (MgSO4), filtered, and concentrated to afford a brown oil. Purification by flash column chromatography on silica gel using 2% MeOH/CH2Cl2 afforded [1-(3-methyl-but-2-enyl)-1H-benzoimidazol-2-yl]-methanol as a pale yellow solid (241 mg, 36%). 1H NMR (CDCl3) δ 1.72 (s, 3H), 1.87 (s, 3H), 4.80 (d, 2H, J=6.6 Hz), 4.86 (s, 2H), 5.21 (td, 1H, J=6.0, 1.2 Hz), 7.19-7.23 (m, 3H), 7.65-7.68 (m, 1H).

Provenance & Evidence