1.1: triethylamine / 2 h / 80 °C 2.1: potassium fluoride / dimethyl sulfoxide / 4 h / 90 °C 3.1: sodium hydrogencarbonate; water / 4 h / 100 °C 3.2: 1.17 h / 20 °C 4.1: water; sodium hydroxide / toluene / 0.5 h / 20 °C 4.2: 0.5 h / 15 - 25 °C View Scheme