1: trans-cyclooctene With ozone in methanol; dichloromethane T=-70°C; 8 h; 2: With toluene-4-sulfonic acid in methanol; dichloromethane T=-70°C; 6 h; 3: dimethoxy sulfoxide With sodium hydrogencarbonate more than 3 stages;

1: methanol; cyclooctene With ozone in dichloromethane T=-70°C; 8 h; 2: With toluene-4-sulfonic acid in dichloromethane T=-70°C; 6 h; 3: dimethoxy sulfoxide With sodium hydrogencarbonate more than 3 stages;

pyridinium chlorochromate in dichloromethane T=20°C; 2 h;

1: With ozone in dichloromethane T=-78°C; 2: With toluene-4-sulfonic acid T=-78 - 20°C; 3: With dimethylsulfide; sodium hydrogencarbonate

1: 89 percent / tetrahydrofuran; diethyl ether / 0.5 h / 0 °C 2: 97 percent / p-TsOH / tetrahydrofuran; H2O; propan-2-ol / 0.5 h / Heating View Scheme

1: 89 percent / tetrahydrofuran; diethyl ether / 0.5 h / 0 °C 2: 97 percent / p-TsOH / tetrahydrofuran; H2O; propan-2-ol / 0.5 h / Heating 3: 1) sodium hexamethyldisilazide / 1) THF, toluene, 25 deg C, 2 h, 2) THF, a) -100 deg C, 30 min, 2) to 25 deg C, 3 h 4: p-TsOH / tetrahydrofuran; H2O / 0.08 h / Heating 5: 1-Methylcyclohex-1-ene, NaClO2, H2NSO3H / CH2Cl2; H2O / 1) 0 deg C, 15 min, 2) to 25 deg C, 30 min View Scheme

1: 89 percent / tetrahydrofuran; diethyl ether / 0.5 h / 0 °C 2: 97 percent / p-TsOH / tetrahydrofuran; H2O; propan-2-ol / 0.5 h / Heating 3: 1) sodium hexamethyldisilazide / 1) THF, toluene, 25 deg C, 2 h, 2) THF, a) -100 deg C, 30 min, 2) to 25 deg C, 3 h 4: p-TsOH / tetrahydrofuran; H2O / 0.08 h / Heating 5: 1-Methylcyclohex-1-ene, NaClO2, H2NSO3H / CH2Cl2; H2O / 1) 0 deg C, 15 min, 2) to 25 deg C, 30 min 6: 72 percent / Ph3P, diethyl azodicarboxylate / toluene View Scheme