potassium carbonate in N,N-dimethyl-formamide 2 h; Ambient temperature;

1: 1.) Br2 / 1.) CCl4, -5 deg C, 1 h 2.) 2 h, 0 deg C, yield 92 percent 2: 64 percent / potassium carbonate / dimethylformamide / 2 h / Ambient temperature View Scheme

1: 96 percent / HCl / ethanol / 0.5 h / Heating 2: 1.) Br2 / 1.) CCl4, -5 deg C, 1 h 2.) 2 h, 0 deg C, yield 92 percent 3: 64 percent / potassium carbonate / dimethylformamide / 2 h / Ambient temperature View Scheme

1: 100 percent / 48 h / Ambient temperature 2: 96 percent / HCl / ethanol / 0.5 h / Heating 3: 1.) Br2 / 1.) CCl4, -5 deg C, 1 h 2.) 2 h, 0 deg C, yield 92 percent 4: 64 percent / potassium carbonate / dimethylformamide / 2 h / Ambient temperature View Scheme

potassium hydroxide in ethanol Heating;

(i) ClCH2CH2Cl, (ii) piperidine, dioxane; Multistep reaction;