To a solution of N-methylformanilide (30 g), butyl vinyl ether (22.2 g) in 15 ml of acetonitrile under stirring at 5° C., a solution of bis-trichloromethylcarbonate (26.1 g) in 70 ml of acetonitrile is added dropwise in 80 min. The reaction mixture is kept under stirring at 5° C. overnight, then phosphorus oxychloride (31.4 g) is added dropwise in 30 minutes, then the reaction mixture is stirred at 5° C. for 15 minutes. 3-[3-(4-Fluorophenyl)-1-(1-Methylethyl)-1H-Indole (35.8 g) and acetonitrile (25 ml) are added. The mixture is warmed to 80° C. and kept under stirring for about 24 hours. The reaction mixture is worked up as described in Example 3b to give the product (69% yield).
