1: 80 percent / K2CO3 / dimethylformamide / 72 h / Ambient temperature 2: 40 percent / K2CO3 / dimethylformamide / 48 h 3: 85 percent / conc. HCl / acetic acid; H2O / 10 h / 100 °C 4: dimethylformamide / 10 h / 110 °C View Scheme

1: 40 percent / K2CO3 / dimethylformamide / 48 h 2: 85 percent / conc. HCl / acetic acid; H2O / 10 h / 100 °C 3: dimethylformamide / 10 h / 110 °C View Scheme

in N,N-dimethyl-formamide T=110°C; 10 h; Yield given;