1: 1.) TosCl; 2.) LiCl / 1.) pyridine; 2.) DMF 2: 93 percent / titanium tetrachloride / diethyl ether 3: 97 percent / potassium t-butoxide / tetrahydrofuran / 2 h / Heating 4: 90 percent / aq. oxalic acid / Ambient temperature 5: CH2Cl2 / Ambient temperature 6: RuO2, NaIO4 / acetone; H2O 7: H3O(1+) / H2O / 6 h / Heating View Scheme