1: 79 percent / toluene / 20 °C 2: 1,4-diazabicyclo<2.2.2>octane / benzene / 0.07 h / Ambient temperature 3: 65 percent / toluene / 1 h / Heating 4: NaOH / H2O; tetrahydrofuran / 18 h / Ambient temperature 5: 73 percent / toluene-p-sulphonic acid hydrate / toluene / 9 h / Heating View Scheme

1: 79 percent / toluene / 20 °C 2: 1,4-diazabicyclo<2.2.2>octane / benzene / 0.07 h / Ambient temperature 3: 65 percent / toluene / 1 h / Heating 4: NaOH / H2O; tetrahydrofuran / 18 h / Ambient temperature View Scheme

1: 79 percent / toluene / 20 °C 2: 1,4-diazabicyclo<2.2.2>octane / benzene / 0.07 h / Ambient temperature 3: 65 percent / toluene / 1 h / Heating 4: magnesium / 1.) ether, 60 min, RT, 2.) 19 h View Scheme

N-bromosuccinmide; 2,2'-azo-bisisobutyronitrile in tetrachloromethane 0.5 h; HeatingIrradiation;

1: 79 percent / toluene / 20 °C 2: 1,4-diazabicyclo<2.2.2>octane / benzene / 0.07 h / Ambient temperature View Scheme