1: NaBH4 / methanol / 3 h / Ambient temperature 2: LiAlH4 / tetrahydrofuran / 2 h / -50 °C 3: p-TsOH / acetone / 10 h / Ambient temperature View Scheme

Multi-step reaction with 7 steps 1: 99 percent / 2N aq. HCl / methanol / 3 h / Heating2: imidazole / tetrahydrofuran / 1.5 h / 0 - 20 °C3: TEA, DMAP / CH2Cl2 / 0.17 h / 0 °C4: 1.) PdCl2(CH3CN)2, 2.) n-Bu4NF, 3.) aq. K2CO3 5: TEA, DMAP / CH2Cl2 / Ambient temperature6: PdCl2(CH3CN)2 / CH2Cl2 / 2 h / Ambient temperature7: 1.) O3, 2.) Me2S / 1.) MeOH. -78 deg C, 2.) MeOH, RT, 5 h  

Multi-step reaction with 6 steps 1: imidazole / tetrahydrofuran / 1.5 h / 0 - 20 °C2: TEA, DMAP / CH2Cl2 / 0.17 h / 0 °C3: 1.) PdCl2(CH3CN)2, 2.) n-Bu4NF, 3.) aq. K2CO3 4: TEA, DMAP / CH2Cl2 / Ambient temperature5: PdCl2(CH3CN)2 / CH2Cl2 / 2 h / Ambient temperature6: 1.) O3, 2.) Me2S / 1.) MeOH. -78 deg C, 2.) MeOH, RT, 5 h