Hydrochloric Acid → 1-(1-(tetrahydro-2H-pyran-2-yl)-1H-benzo[d]imidazol-4-yl)ethanone

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-benzo[d]imidazole (1.6 g, 6 mmol), tributyl(1-ethoxyvinyl)stannane (2.4 g, 6 mmol), Pd(PPh3)4 (0.7 g, 0.6 mmol), K3PO4 (2.5 g, 12 mmol) in NMP (10 mL) was heated at 80° C. for 6 h. The mixture was cooled to RT, water was added and the mixture was extracted with EtOAc (50 mL×3). HCl (1.0 eq) was added to the combined extract and the resulting mixture was stirred for 30 min. The pH of the mixture was adjusted to ˜8 by addition of aqueous NH4OH solution (35%). The aqueous phase was extracted with EtOAc (50 mL×3). The combined extracts were dried (MgSO4), filtered, and concentrated in vacuo. The residue was purified by SiO2 chromatography eluting with petroleum ether:EtOAc (10:1) to afford 1-(1-(tetrahydro-2H-pyran-2-yl)-1H-benzo[d]imidazol-4-yl)ethanone as a gray solid (0.8 g, 59%). MS (ESI): m/z=245.1 [M+1]+.

Provenance & Evidence