1.1: Br2; PPh3 / dimethylformamide / 2 h / 20 °C 2.1: K2CO3 / dimethylformamide / 0.33 h / 20 °C 2.2: 1.59 g / dimethylformamide / 14 h / 20 °C 3.1: 100 percent / TFA / CH2Cl2 / 1 h / 20 °C View Scheme

1.1: K2CO3 / dimethylformamide / 0.33 h / 20 °C 1.2: 1.59 g / dimethylformamide / 14 h / 20 °C 2.1: 100 percent / TFA / CH2Cl2 / 1 h / 20 °C View Scheme

1: 84 percent / CH2Cl2 / 2 h / Ambient temperature 2: 1.) BuLi / 1.) hexane, THF, -78 deg C, 15 min; 2.) THF, 1 h, RT View Scheme

n-butyllithium 1.) hexane, THF, -78 deg C, 15 min; 2.) THF, 1 h, RT; Yield given. Multistep reaction;