1: 96 percent / H2 / Pd/C / ethyl acetate / 2.5 h / 20 °C 2: 71.2 percent / HOBt; DCC / CH2Cl2 / 6 h / 20 °C 3: 94.6 percent / Lawesson's reagent / benzene / 3 h / 80 °C 4: 51.4 percent / Raney-Ni / tetrahydrofuran / 4 h / 20 °C 5: 93 percent / TFA / 3 h / 20 °C View Scheme