3,4-dihydro-2H-pyran → 4-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-benzo[d]imidazole

Participants

Reaction Conditions

Reaction Steps

To a mixture of 52 (1.30 g, 6.6 mmol) and 3,4-dihydro-2H-pyran (2.78 g, 33.0 mmol) in THF (15 mL) was added p-TsOH.H2O (0.11 g, 0.66 mmol). The mixture was stirred at 80° C. for 14 h, then the solvent was removed in vacuo. The residue was purified by SiO2 chromatography eluting with 10% petroleum ether/EtOAc to afford 1.3 g (70%) 4-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-benzo[d]imidazole (54) as brown oil: MS (ESI) m/z=281.0 [M+1]+.

Provenance & Evidence