1: With morpholine; sulfur T=110°C; 12 h; 2: With hydrogenchloride; acetic acid in water 8 h; Reflux;

1: 63 percent / K2CO3, Cu / 10 h / Heating 2: 1.) morpholine, sulfur, 2.) glacial acetic acid, conc. aq. HCl / 1.) reflux, 12 h, 2.) reflux, 8 h View Scheme

potassium hydroxide in methanol 72 h; Heating;

1: phenol, copper / 24 h / 120 - 125 °C 2: sulfur / 24 h / Heating 3: KOH / methanol / 72 h / Heating View Scheme

1: 63 percent / K2CO3, Cu / 10 h / Heating 2: 1.) morpholine, sulfur, 2.) glacial acetic acid, conc. aq. HCl / 1.) reflux, 12 h, 2.) reflux, 8 h View Scheme

1.1: sulfuric acid / 2 h / 50 °C 2.1: sodium t-butanolate / tert-butyl methyl ether / 2 h / 5 - 20 °C 3.1: (S)-pyrophosphoric acid / water / 2 h / 0 - 60 °C 4.1: 1,8-diazabicyclo[5.4.0]undec-7-ene / 20 - 35 °C 5.1: hydrogen / Ni-Raney / tetrahydrofuran / 48 h / 20 °C / 2585.81 - 3102.97 Torr 6.1: ethyl acetate / 96 h / 25 °C 7.1: boron trifluoride diethyl etherate; triethylsilane / 24 h / 105 °C 8.1: sodium hydroxide / dichloromethane; water / pH > 10 8.2: 2 h / 60 °C View Scheme

1.1: sulfuric acid / 2 h / 50 °C 2.1: sodium t-butanolate / tert-butyl methyl ether / 2 h / 5 - 20 °C 3.1: (S)-pyrophosphoric acid / water / 2 h / 0 - 60 °C 4.1: 1,8-diazabicyclo[5.4.0]undec-7-ene / 20 - 35 °C 5.1: hydrogen / Ni-Raney / tetrahydrofuran / 48 h / 20 °C / 2585.81 - 3102.97 Torr 6.1: ethyl acetate / 96 h / 25 °C 7.1: lithium aluminium tetrahydride; AlCl3, aluminium chloride / tetrahydrofuran / 0 - 20 °C 7.2: 0.33 h / 2 °C View Scheme

1: thionyl chloride / toluene 2: triethylamine / N,N-dimethyl-formamide 3: potassium tert-butylate / toluene 4: phosphoric acid; phosphorous pentoxide / toluene View Scheme

1: thionyl chloride / toluene 2: triethylamine / N,N-dimethyl-formamide 3: potassium tert-butylate / toluene View Scheme

PPA T=100 - 105°C;