1: 96 percent / K2CrO4 / acetic acid; H2O / Ambient temperature 2: 100 percent / KOH / methanol / 12 h / Heating 3: p-toluenesulfonic acid / Ambient temperature 4: t-butylamine-borane complex / CH2Cl2 / 2 h / Ambient temperature 5: 83 percent / pyridine / 24 h / Ambient temperature 6: 76 percent / 65 h / 80 °C 7: 78 percent / conc. aq. HCl / methanol / 40 h / 25 °C 8: KOH / methanol / 1 h / Heating View Scheme

1: 96 percent / K2CrO4 / acetic acid; H2O / Ambient temperature 2: 100 percent / KOH / methanol / 12 h / Heating 3: p-toluenesulfonic acid / Ambient temperature 4: t-butylamine-borane complex / CH2Cl2 / 2 h / Ambient temperature 5: 83 percent / pyridine / 24 h / Ambient temperature 6: 76 percent / 65 h / 80 °C 7: 78 percent / conc. aq. HCl / methanol / 40 h / 25 °C 8: KOH / methanol / 1 h / Heating View Scheme

Multi-step reaction with 2 steps 1: 1.) Li/NH3 2: 86 percent / 4-dimethylaminopyridine / benzene; pyridine / 0.08 h / Ambient temperature  

With  potassium dichromate in  water; acetic acid  Ambient temperature;   

Multi-step reaction with 4 steps 1: 96 percent / K2CrO4 / acetic acid; H2O / Ambient temperature2: 100 percent / KOH / methanol / 12 h / Heating3: p-toluenesulfonic acid / Ambient temperature4: 88 percent / pyridine / 24 h / Ambient temperature  

Multi-step reaction with 5 steps 1: 96 percent / K2CrO4 / acetic acid; H2O / Ambient temperature2: 100 percent / KOH / methanol / 12 h / Heating3: p-toluenesulfonic acid / Ambient temperature4: 88 percent / pyridine / 24 h / Ambient temperature5: 95 percent / 65 h / 80 °C