1: With lithium hydroxide; water in 1,4-dioxane; ethanol T=20 - 40°C; 2: With hydrogenchloride in 1,4-dioxane; ethanol; water pH=~ 4;

1: 85 percent / N-bromosuccinimide / CCl4 / 3 h / Heating; Irradiation 2: 70 percent / sodium ethoxide, 2-nitropropane / ethanol / 2 h / Heating 3: 41 percent / hydroxylamine hydrochloride / ethanol / 16 h / Ambient temperature 4: 61 percent / SOCl2 / diethyl ether / 16 h / Ambient temperature View Scheme