ozone; dihydrogen peroxide in formic acid; dichloromethane; water

1: 1) O3; 2) NaBH4 / 1) -78 deg C, CH2Cl2, methanol; 2) 95percent ethanol, -40 deg C, 1 h 2: 1) N,N'-dicyclohexylcarbodiimide, dichloroacetic acid; 2) oxalic acid / 1) dimethyl sulfoxide, 3 h, room temp.; 2) methanol View Scheme