1: 1.05 g / KI, CF3COOH / methanol / 20 h / Ambient temperature 2: 69 percent / N-bromosuccinimide, dibenzoylperoxide / CCl4 / 20 h / Heating 3: 68 percent / NaOMe / dimethylformamide / Ambient temperature 4: 65 percent / dimethylformamide / Heating View Scheme