1: 1) Mg / 1) diethyl ether, 2) rt, 2 h 2: BF3*Et2O / CH2Cl2 / 0.5 h / -78 °C 3: 77 percent / MnO2 / various solvent(s) / 120 h / 180 °C 4: 1) 10 M BH3*SMe2, 2) 10percent aq. NaOH, 30percent aq. H2O2 / 1) THF, 0 deg C, 1 h, 2) rt, 6 h 5: 94 percent / oxalyl chloride, DMSO, NEt3 / CH2Cl2 / -78 °C 6: 35 percent / KMnO4, MgSO4 / acetone / 2 h View Scheme

1: 1) Mg / 1) diethyl ether, 2) rt, 2 h 2: BF3*Et2O / CH2Cl2 / 0.5 h / -78 °C 3: 77 percent / MnO2 / various solvent(s) / 120 h / 180 °C 4: 1) 10 M BH3*SMe2, 2) 10percent aq. NaOH, 30percent aq. H2O2 / 1) THF, 0 deg C, 1 h, 2) rt, 6 h 5: 94 percent / oxalyl chloride, DMSO, NEt3 / CH2Cl2 / -78 °C 6: 50 percent / KMnO4, MgSO4 / acetone / 2 h View Scheme

1: 1) Mg / 1) diethyl ether, 2) rt, 2 h 2: BF3*Et2O / CH2Cl2 / 0.5 h / -78 °C 3: 77 percent / MnO2 / various solvent(s) / 120 h / 180 °C View Scheme

1: 1) Mg / 1) diethyl ether, 2) rt, 2 h 2: BF3*Et2O / CH2Cl2 / 0.5 h / -78 °C 3: 77 percent / MnO2 / various solvent(s) / 120 h / 180 °C 4: 1) 10 M BH3*SMe2, 2) 10percent aq. NaOH, 30percent aq. H2O2 / 1) THF, 0 deg C, 1 h, 2) rt, 6 h View Scheme

1: 1) Mg / 1) diethyl ether, 2) rt, 2 h 2: BF3*Et2O / CH2Cl2 / 0.5 h / -78 °C 3: 77 percent / MnO2 / various solvent(s) / 120 h / 180 °C 4: 1) 10 M BH3*SMe2, 2) 10percent aq. NaOH, 30percent aq. H2O2 / 1) THF, 0 deg C, 1 h, 2) rt, 6 h 5: 94 percent / oxalyl chloride, DMSO, NEt3 / CH2Cl2 / -78 °C View Scheme