hydrogen cation in methanol; water T=40°C; pH 3.5, MeOH/aqueous buffer (5:95); other pH; Rate constantMechanism;

1: 47.9 percent / aq. sodium acetate, aq. acetic acid, KI / ethanol; H2O / 30 h / 37 - 40 °C / pH=4.5 2: 89 percent / pyridine / 12 h 3: 50 percent / 4-(dimethylamino)pyridine / acetonitrile / 12 h / 24 °C 4: 65 percent / tributyltin hydride, azobisisobutyronitrile / toluene / 3 h / Heating View Scheme

1: 47.9 percent / aq. sodium acetate, aq. acetic acid, KI / ethanol; H2O / 30 h / 37 - 40 °C / pH=4.5 2: 89 percent / pyridine / 12 h 3: 50 percent / 4-(dimethylamino)pyridine / acetonitrile / 12 h / 24 °C View Scheme

1: sodium nitrite; HBF4 / H2O 2: methanol 3: H2 / Pd/C View Scheme