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

1: 82.7 percent / copper-bronze, copper(I) iodide, K2CO3 / dimethylformamide / 4 h / 140 °C 2: 101 g / conc. H2SO4 / 1 h / 50 °C 3: 9 g / AcOH, aq. HCl / 2 h / 60 °C 4: 89 percent / dimethylformamide / 2 h / Ambient temperature View Scheme

1: 9 g / AcOH, aq. HCl / 2 h / 60 °C 2: 89 percent / dimethylformamide / 2 h / Ambient temperature View Scheme

1: 101 g / conc. H2SO4 / 1 h / 50 °C 2: 9 g / AcOH, aq. HCl / 2 h / 60 °C 3: 89 percent / dimethylformamide / 2 h / Ambient temperature View Scheme

1: 82.7 percent / copper-bronze, copper(I) iodide, K2CO3 / dimethylformamide / 4 h / 140 °C 2: 101 g / conc. H2SO4 / 1 h / 50 °C 3: 9 g / AcOH, aq. HCl / 2 h / 60 °C 4: 89 percent / dimethylformamide / 2 h / Ambient temperature View Scheme