1: 98 percent / triethylamine / tetrahydrofuran / 0.5 h / 25 °C 2: 73 percent / 1,5-diazabicyclo<5.4.0>undec-5-ene / dimethylformamide / 2 h / -15 °C 3: 97 percent / diethyl ether / 0.5 h / 0 °C 4: 54 percent / bromine / acetic acid / 2 h / Ambient temperature 5: 20 percent / 1,5-diazabicyclo<5.4.0>undec-5-ene / benzene / 0.75 h 6: 1) boron tribromide, 2) conc. aq. hydrochloric acid / 1) dichloromethane, reflux, 30 min, 2) 30 min 7: 82 percent / sodium methoxide / methanol / 0.5 h View Scheme

Multi-step reaction with 6 steps 1: triethylamin / tetrahydrofuran / 0.17 h / 25 °C2: 1,8-diazabicyclo<5.4.0>undec-7-ene / dimethylformamide / -15 °C4: bromine / acetic acid5: 1,8-diazabicyclo<5.4.0>undec-7-ene / benzene6: boron tribromide / CH2Cl2 / 0.5 h / Heating