3,4-dihydro-2H-pyran → 5-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-benzo[d]imidazole

Participants

Reaction Conditions

Reaction Steps

A mixture of 78 (4.5 g, 23 mmol), 3,4-dihydro-2H-pyran (9 mL, 0.1 mol), p-TsOH.H2O (1.0 g, 3.4 mmol) in THF (200 mL) was stirred under nitrogen at 80° C. for 18 h. The reaction mixture was concentrated in vacuo. The crude product was purified by SiO2 chromatography eluting with DCM/MeOH (100:1) to afford 6.0 g (100%) of 5-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-benzo[d]imidazole (80) as yellow oil: MS (ESI) m/z=281.0 (M+1).

Provenance & Evidence