T=40°C; 20 h; Irradiation;

ammonium acetate in ethanol Mannich reaction; 3 h; Heating;

in benzene T=220°C; 40 h;

1: Na2SO4 / benzene / 12 h / Ambient temperature 2: 23 percent / benzene / 40 h / 220 °C View Scheme

1: 80 percent / NaOH, benzyltriethylammonium chloride / CH2Cl2; H2O / 2 h / 40 °C 2: 74 percent / conc. HCl / tetrahydrofuran; H2O / 8 h / 60 °C 3: Na2SO4 / benzene / 12 h / Ambient temperature 4: 23 percent / benzene / 40 h / 220 °C View Scheme

1: Na2SO4 / benzene / 12 h / Ambient temperature 2: 23 percent / benzene / 40 h / 220 °C View Scheme

1: 74 percent / conc. HCl / tetrahydrofuran; H2O / 8 h / 60 °C 2: Na2SO4 / benzene / 12 h / Ambient temperature 3: 23 percent / benzene / 40 h / 220 °C View Scheme