1: in toluene 0.25 h; Heating; 2: With 1,8-diazabicyclo[5.4.0]undec-7-ene in toluene 0.333333 h; Heating;

1.1: 87 percent / N-bromosuccinimide / dimethylformamide / 2 h / 0 °C 2.1: 79 percent / Lawesson's reagent / toluene / 0.75 h / Heating 3.1: 22 percent / K2CO3; 18-crown-6 / tetrahydrofuran / 3 h / 20 °C 4.1: toluene / 0.25 h / Heating 4.2: 42 percent / DBU / toluene / 0.33 h / Heating View Scheme

1.1: 79 percent / Lawesson's reagent / toluene / 0.75 h / Heating 2.1: 22 percent / K2CO3; 18-crown-6 / tetrahydrofuran / 3 h / 20 °C 3.1: toluene / 0.25 h / Heating 3.2: 42 percent / DBU / toluene / 0.33 h / Heating View Scheme

1.1: 22 percent / K2CO3; 18-crown-6 / tetrahydrofuran / 3 h / 20 °C 2.1: toluene / 0.25 h / Heating 2.2: 42 percent / DBU / toluene / 0.33 h / Heating View Scheme