disodium hydrogenphosphate; bromine in 1,4-dioxane 4 h; Ambient temperature;

1: 71 percent / sodium hydrogen phosphate, Br2 / dioxane / 4 h / Ambient temperature 2: 1) NaH / 1) DMF, 40 deg C, 30 min, 2) 100 deg C, 9 h 3: 82 percent / H2SO4 / H2O / 48 h / Ambient temperature View Scheme