1: p-TsOH*H2O / toluene / 0.5 h / Heating 2: 1.) POCl3 / 1.) CH2Cl2, 30 min, 2.) CH2Cl2, reflux, 2.5 h 3: NaBH4 / tetrahydrofuran 4: pyridine, SOCl2 / CH2Cl2 / Ambient temperature 5: 1.) NaH / 1.) DMF, 30 min, 2.) DMF, 15 min 6: 78 percent / hydrolysis View Scheme

Multi-step reaction with 5 steps 1: p-TsOH*H2O / toluene / 0.5 h / Heating2: 1.) POCl3 / 1.) CH2Cl2, 30 min, 2.) CH2Cl2, reflux, 2.5 h3: NaBH4 / tetrahydrofuran4: pyridine, SOCl2 / CH2Cl2 / Ambient temperature5: 1.) NaH / 1.) DMF, 30 min, 2.) DMF, 15 min  

With  toluene-4-sulfonic acid in  toluene 0.5 h;  Heating;  Yield given;