1: 97 percent / 48percent aq. HF / acetonitrile / 1 h / 25 °C 2: H2, norbornadiene<1,4-bis(diphenylphosphino)butane>rhodium(I) tetrafluoroborate / CH2Cl2 / 12 h / 760 Torr 3: 92 percent / triethylamine, pyridine*SO3 / dimethylsulfoxide / 0.67 h / 25 °C 4: 1.) di-n-butylboryl triflate, diisopropylethylamine / 1.) CH2Cl2, -78 deg C, 30 min, 2a.) -78 deg C, 1 h, 2b.) 0 deg C, 1.5 h 5: 72 percent / pyridine, CrO3 / CH2Cl2 / 0.25 h 6: 84 percent / 40percent aq. HF / acetonitrile / 1 h / 25 °C 7: 1 N aq. LiOH / 1,2-dimethoxy-ethane / 0.75 h / 25 °C View Scheme

With  hydrogen fluoride in  acetonitrile T=25°C; 1 h;   

Multi-step reaction with 8 steps 1: oxalyl chloride, DMSO / CH2Cl2 / 0.5 h / -78 °C2: toluene / 12 h / 70 °C3: 98 percent / diisobutylaluminum hydride (DIBAH) / CH2Cl2 / 1.) -78 deg C, 30 min, 2.) 0 deg C, 30 min4: 6.34 g / methyltriphenoxyphosphonium iodide / dimethylformamide / 0.25 h / 25 °C5: 1.) sodium bis(trimethylsilyl)amide / 1.) THF, -78 deg C, 30 min, 2.) -50 deg C, 10 h6: 84 percent / LiAlH4 / tetrahydrofuran / 1.) -78 deg C, 10 min, 2.) 0 deg C, 60 min7: oxalyl chloride, DMSO / CH2Cl2 / 0.5 h / -78 °C / 1.) CH2Cl2, -78 deg C, 30 min, 2.) -78 deg C, 15 min8: CH2Cl2 / 12 h / 25 °C  

Multi-step reaction with 5 steps 1: 6.34 g / methyltriphenoxyphosphonium iodide / dimethylformamide / 0.25 h / 25 °C2: 1.) sodium bis(trimethylsilyl)amide / 1.) THF, -78 deg C, 30 min, 2.) -50 deg C, 10 h3: 84 percent / LiAlH4 / tetrahydrofuran / 1.) -78 deg C, 10 min, 2.) 0 deg C, 60 min4: oxalyl chloride, DMSO / CH2Cl2 / 0.5 h / -78 °C / 1.) CH2Cl2, -78 deg C, 30 min, 2.) -78 deg C, 15 min5: CH2Cl2 / 12 h / 25 °C  

Multi-step reaction with 4 steps 1: 1.) sodium bis(trimethylsilyl)amide / 1.) THF, -78 deg C, 30 min, 2.) -50 deg C, 10 h2: 84 percent / LiAlH4 / tetrahydrofuran / 1.) -78 deg C, 10 min, 2.) 0 deg C, 60 min3: oxalyl chloride, DMSO / CH2Cl2 / 0.5 h / -78 °C / 1.) CH2Cl2, -78 deg C, 30 min, 2.) -78 deg C, 15 min4: CH2Cl2 / 12 h / 25 °C  

Multi-step reaction with 6 steps 1: 98 percent / diisobutylaluminum hydride (DIBAH) / CH2Cl2 / 1.) -78 deg C, 30 min, 2.) 0 deg C, 30 min2: 6.34 g / methyltriphenoxyphosphonium iodide / dimethylformamide / 0.25 h / 25 °C3: 1.) sodium bis(trimethylsilyl)amide / 1.) THF, -78 deg C, 30 min, 2.) -50 deg C, 10 h4: 84 percent / LiAlH4 / tetrahydrofuran / 1.) -78 deg C, 10 min, 2.) 0 deg C, 60 min5: oxalyl chloride, DMSO / CH2Cl2 / 0.5 h / -78 °C / 1.) CH2Cl2, -78 deg C, 30 min, 2.) -78 deg C, 15 min6: CH2Cl2 / 12 h / 25 °C