Boron tribromide → HCID 15951419, compound

Participants

Reaction Steps

To a suspension of 2-amino-5-(3-methoxyphenyl)-3-methyl-5-pyridin-4-yl-3,5-dihydro-4H-imidazol-4-one (0.75 g, 2.5 mmol) in CH2Cl2 (7.5 mL) is added BBr3 (1.0 M in CH2Cl2, 15 mL, 15 mmol) at −78° C. After addition, the reaction mixture is warmed to room temperature and stirred for 3 h. The reaction mixture is poured into ice-water (50 mL) and the two layers are separated. The aqueous is neutralized with 50% aqueous NaOH to pH˜7 and extracted with 4/1 CH2Cl2/2-PrOH (3×100 mL). The combined organic extracts are washed with brine (150 mL), dried (Na2SO4) and concentrated. The resultant residue is purified by chromatography (silica gel, EtOAc/2M methanolic NH3: 95/5) to give the title compound (0.58 g, 79%) as a solid. Mp: 245-247° C.; MS(+) ES: 283 (M+H)+.

Provenance & Evidence