1: p-TsOH.H2O / methanol / 4 h / Ambient temperature 2: pyridine 3: LiBr.H2O / dimethylformamide / 2.5 h / 80 - 90 °C 5: 50 percent aq. K2CO3 / methanol / 0.25 h / Ambient temperature View Scheme

Multi-step reaction with 2 steps 1: p-TsOH.H2O / methanol / 4 h / Ambient temperature2: pyridine  

Multi-step reaction with 3 steps 1: p-TsOH.H2O / methanol / 4 h / Ambient temperature2: pyridine3: LiBr.H2O / dimethylformamide / 2.5 h / 80 - 90 °C  

With  toluene-4-sulfonic acid in  methanol 4 h;  Ambient temperature;  Yield given;