Multistep reaction;

1: 89 percent / pyridine 2: 83 percent / acetolysis 3: 62 percent / tin(IV) chloride 4: 84 percent / deacylation 5: 49 percent / diphenylcarbonate, NaHCO3 / dimethylformamide / 0.42 h / 144 - 145 °C View Scheme

1: 89 percent / pyridine 2: 83 percent / acetolysis 3: 62 percent / tin(IV) chloride 4: 84 percent / deacylation View Scheme