1: 100 percent / AlBr3 / acetonitrile 2: 87 percent / potassium carbonate / acetone / Heating 3: 92 percent / aluminum bromide / acetonitrile / 1 h / 0 °C 4: 91 percent / concd. hydrochloric acid / methanol / 10 h / Heating 5: 1.) N,N-diisopropylethylamine, 2.) potassium carbonate / 1.) CH2Cl2, RT, 30 min, 2.) MeOH, reflux, 1.5 h 6: hydrochloric acid, acetic acid / 1 h / Ambient temperature View Scheme