1: 1) O3, 2) Me2S / 1) CH2Cl2, -78 deg C, 45 min, 2) to r.t., 7 h 2: 67 percent / NaIO4, 2 percent RuCl3*3H2O / acetonitrile; CCl4 / 0.33 h / Ambient temperature; phosphate buffer, pH 7 3: 96 percent / HOAc / H2O / 8 h / 75 °C 4: 74 percent / 2-chloro-1-methylpyridinium iodide, 4-(dimethylamino)pyridine / acetonitrile / a) 0 deg C, 3 h, b) r.t., 10 h 5: 91 percent / (i-Pr)2NEt / tetrahydrofuran / 15 h / 50 °C 6: 1) N-isopropylcyclohexylamine, n-BuLi / 1) THF, hexane, -60 to -50 deg C, 45 min, 2a) -60 deg C, 45 min, 2b) to -20 deg C, 10 min 7: Et3N, 4-(dimethylamino)pyridine / CH2Cl2 / 6 h 8: 1,8-diazabicyclo<5.4.0>undec-7-ene / CH2Cl2 / 15 h / 4 °C 9: 90 percent / 3 M aq. HCl / tetrahydrofuran / a) r.t., 1 h, b) 35 deg C, 10 h 10: 60 percent / RuCl3*3H2O, 30 percent aq. H2O2 / tetrahydrofuran / a) 0 deg C, 0.5 h, b) r.t., 2 h 11: 91 percent / camphorsulfonic acid / CHCl3 / 12 h / Ambient temperature View Scheme

Multi-step reaction with 3 steps 1: 67 percent / pyridinium dichromate / dimethylformamide / 30 h / Ambient temperature2: 99 percent / diethyl ether3: 93 percent / Ti(OEt)4 / 60 h / 100 °C  

Multi-step reaction with 5 steps 1: 98 percent / camphorsulfonic acid / CH2Cl2 / 5 h2: 90 percent / LiAlH4 / diethyl ether / 1 h / Heating3: 67 percent / pyridinium dichromate / dimethylformamide / 30 h / Ambient temperature4: 99 percent / diethyl ether5: 93 percent / Ti(OEt)4 / 60 h / 100 °C  

Multi-step reaction with 4 steps 1: 90 percent / LiAlH4 / diethyl ether / 1 h / Heating2: 67 percent / pyridinium dichromate / dimethylformamide / 30 h / Ambient temperature3: 99 percent / diethyl ether4: 93 percent / Ti(OEt)4 / 60 h / 100 °C  

Multi-step reaction with 6 steps 1: 51 percent / Ti(O-i-Pr)4 / benzene / 0.33 h2: 98 percent / camphorsulfonic acid / CH2Cl2 / 5 h3: 90 percent / LiAlH4 / diethyl ether / 1 h / Heating4: 67 percent / pyridinium dichromate / dimethylformamide / 30 h / Ambient temperature5: 99 percent / diethyl ether6: 93 percent / Ti(OEt)4 / 60 h / 100 °C  

 Yield given. Multistep reaction;