Sodium Bicarbonate → 3-isopropenyl-1-{2-[4-((5-fluoro-3-indolyl)methyl)piperidino]ethyl}-2H-benzimidazol-2-one

Participants

Reaction Conditions

Reaction Steps

3-Isopropenyl-{2-[4-((5-fluoro-3-indolyl)methyl)piperidino]ethyl}-2H-benzimidazolin-2-one may be prepared in the following manner: the procedure is as in Example 25, starting with 3-isopropenyl-1-(2-chloroethyl)-2H-benzimidazolin-2-one (2.4 g), 4-[(5-fluoro-3-indolyl)methyl]piperidine (2.3 g) and sodium bicarbonate (0.8 g) in a mixture of dimethylformamide (40 cc) and tetrahydrofuran (20 cc). The mixture is heated to boiling for 10 hours and then cooled to a temperature in the region of 20° C. After purification by flash chromatography on a silica column under a stream of nitrogen and moderate pressure (0.5-1.5 bar) with dichloromethane and ethyl acetate as eluents, 3-isopropenyl-1-{2-[4-((5-fluoro-3-indolyl)methyl)piperidino]ethyl}-2H-benzimidazolin-2-one (3 g), m.p. 132° C., is obtained.

Provenance & Evidence