1: 70 percent / borane-pyridine complex, HCl / ethanol / Ambient temperature 2: 84 percent / conc.HCl, NaNO2 / ethanol; H2O / Ambient temperature 3: 3.0 mmol / conc.HCl / 5 h / Heating View Scheme

1: 70 percent / borane-pyridine complex, HCl / ethanol / Ambient temperature 2: 84 percent / conc.HCl, NaNO2 / ethanol; H2O / Ambient temperature 3: 0.7 mmol / conc.HCl / 5 h / Heating View Scheme

1: 70 percent / borane-pyridine complex, HCl / ethanol / Ambient temperature 2: 84 percent / conc.HCl, NaNO2 / ethanol; H2O / Ambient temperature 3: 0.1 mmol / conc.HCl / 5 h / Heating View Scheme

1: 70 percent / borane-pyridine complex, HCl / ethanol / Ambient temperature 2: 84 percent / conc.HCl, NaNO2 / ethanol; H2O / Ambient temperature 3: 0.7 mmol / conc.HCl / 5 h / Heating 5: 83 percent View Scheme