1: 79 percent / 1) thallium (III)nitrate trihydrate; 2) 10percent hydrochloric acid; / methanol / 1) 32-35 deg C; 8 h; 2) reflux; 3 h; 2: 97 percent / hydrogenolyse / 10percent Pd-C / methanol View Scheme

1: 79 percent / 1) thallium (III)nitrate trihydrate; 2) 10percent hydrochloric acid; / methanol / 1) 32-35 deg C; 8 h; 2) reflux; 3 h; 2: 97 percent / hydrogenolyse / 10percent Pd-C / methanol 3: 37 percent / pyridine / diethyl ether / 5.5 h / 2 - 5 °C 4: 18 percent / BF3-etherate / dioxane / 6 h / 51 - 53 °C 5: 50 percent / 4percent aq. NaOH / methanol / 1.5 h / 50 °C View Scheme