tetrafluoroboric acid; [I(py)2]BF4 in dichloromethane T=-80°C; 2 h;

1H-imidazole; triphenylphosphine diiodide in dichloromethane Ambient temperature;

1: 97 percent / ZnI2 / CH2Cl2 / 0 - 20 °C 2: 97 percent / SnCl2*2H2O, AcOH, conc. aq. HCl / 72 h / Heating 3: 10.0 M borane methyl sulfide / tetrahydrofuran / 0 - 20 °C 4: triphenylphosphine diiodide, imidazole / CH2Cl2 / Ambient temperature View Scheme

1: 97 percent / SnCl2*2H2O, AcOH, conc. aq. HCl / 72 h / Heating 2: 10.0 M borane methyl sulfide / tetrahydrofuran / 0 - 20 °C 3: triphenylphosphine diiodide, imidazole / CH2Cl2 / Ambient temperature View Scheme

1,8-diazabicyclo[5.4.0]undec-7-ene in dichloromethane 6 h; Heating;