1.1: sodium hydroxide / water / 6.5 h / 60 °C 2.1: nitric acid / 1.67 h / -15 °C 3.1: sodium hydroxide / water / 0.5 h 3.2: 6.25 h / 0 - 70 °C 4.1: dihydrogen peroxide / methanol; water / 4 h / 5 - 10 °C 5.1: potassium carbonate / N,N-dimethyl-formamide / 0.5 h 5.2: 3.5 h / 5 - 20 °C 6.1: ammonia / ethanol; water / 6 h / 90 °C / Autoclave 7.1: sodium dithionite / methanol; water / 12 h / Reflux View Scheme