Isopropanol → HCID 19955596, compound

Participants

Reaction Steps

To a stirred solution of 4-ethyl-2-propyl-1H-imidazole-5-carboxaldehyde (0.15 g; preparable as described in WO92/00977; Dupont) in dry dimethylformamide (3 ml) was added sodium hydride (60% dispersion in mineral oil; 36 mg) and stirring was continued for approximately 45 minutes. The resulting solution was then added via canula to a stirred solution of 3-(4'-bromomethylbiphenyl-2-yl)-4-isopropoxycyclobut-3-ene-1,2-dione (0.35 g; preparable as in Example 1(c)) in dry dimethylformamide (3 ml). After stirring for 1 hour, 2-propanol (0.1 ml) was added. The mixture obtained was poured into ethyl acetate (20 ml) then washed with water (15 ml). The aqueous washings were extracted with ethyl acetate (10 ml) and the combined organic phases were washed with water (5×15 ml) and dried over magnesium sulphate. The solvent was removed under reduced pressure and the residue obtained was purified by flash chromatography on silica gel (eluting with ethyl acetate/petroleum ether (b.p. 60°-80° C.) (75:25)) to give 4-ethyl-1-[2'-(3,4-dioxo-2-isopropoxycyclobut-1-en-1-yl)biphenyl-4-ylmethyl]-2-propyl-1H-imidazole-5-carboxaldehyde, an active compound of the present invention, as a foam (0.194 g).

Provenance & Evidence