Water → 3-[3-(4-Fluorophenyl)-1-(1-methylethyl)-1H-indol-2-YL]-2-propenal

Participants

Reaction Conditions

Reaction Steps

Use of the crude acrolein coming from Example 3a. To a suspension of 3-[3-(4-Fluorophenyl)-1-(1-Methylethyl)-1H-Indole (35.8 g) phosphorus oxychloride (31.4 g) in acetonitrile (35 ml) cooled at 5° C. a solution of crude acrolein (32.3 g from Example 3a) in acetonitrile (40 ml) is added dropwise in 30 minutes. The reaction mixture is then warmed to 60° C. and kept under stirring at 60° C. for 4 hours; water (300 ml) is added and after 1 hour at 60° C. the formed solid is filtered on Buchner and washed with 75 ml of water. The wet solid (49.7 g) is dissolved in toluene (250 ml), celite (1 g) and charcoal (0.5 g) are added and the mixture is stirred at room temperature for 30 minutes. After filtration of the solid, the solvent is distilled off at reduced pressure and the residue is dissolved at 75° C. with isopropanol (72 ml). The solution is cooled at 20° C. and stirred at room temperature for 1 hour. The precipitate is filtered on Buchner, washed twice with isopropanol (15 ml) and dried at 60° C. under vacuum. 30.2 g (70% molar yield) of the product are obtained.

Provenance & Evidence