1: 76 percent / various solvent(s) / 2 h / 180 °C 2: 33 percent / NaOH, K2S2O8 / pyridine; H2O / 27 h / Ambient temperature 3: 81 percent / K2CO3 / acetone / 24 h / Ambient temperature View Scheme

1: 76 percent / various solvent(s) / 2 h / 180 °C 2: 33 percent / NaOH, K2S2O8 / pyridine; H2O / 27 h / Ambient temperature 3: 95 percent / K2CO3 / acetone / 0.5 h / Heating View Scheme