1: 96 percent / p-toluenesulfonic acid / benzene / Heating 2: 83 percent / lithium diisopropylamide / tetrahydrofuran / -80 °C 3: 90 percent / 1 N aq. HCl / 2 h / 50 °C 4: FClO3, KHCO3 / methanol / 20 °C 5: 36 percent / tri-sec-butylborohydride (K Selectride) / tetrahydrofuran 6: 1.) O3, 2.) (CH3)2S / 1.) MeOH, -70 deg C View Scheme

1: 83 percent / lithium diisopropylamide / tetrahydrofuran / -80 °C 2: 90 percent / 1 N aq. HCl / 2 h / 50 °C 3: FClO3, KHCO3 / methanol / 20 °C 4: 36 percent / tri-sec-butylborohydride (K Selectride) / tetrahydrofuran 5: 1.) O3, 2.) (CH3)2S / 1.) MeOH, -70 deg C View Scheme

1: 90 percent / 1 N aq. HCl / 2 h / 50 °C 2: FClO3, KHCO3 / methanol / 20 °C 3: 36 percent / tri-sec-butylborohydride (K Selectride) / tetrahydrofuran 4: 1.) O3, 2.) (CH3)2S / 1.) MeOH, -70 deg C View Scheme

1: FClO3, KHCO3 / methanol / 20 °C 2: 36 percent / tri-sec-butylborohydride (K Selectride) / tetrahydrofuran 3: 1.) O3, 2.) (CH3)2S / 1.) MeOH, -70 deg C View Scheme

1: 36 percent / tri-sec-butylborohydride (K Selectride) / tetrahydrofuran 2: 1.) O3, 2.) (CH3)2S / 1.) MeOH, -70 deg C View Scheme

dimethylsulfide; ozone 1.) MeOH, -70 deg C; Multistep reaction;