1: 79 percent / mesyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 2: 1) t-butyllithium; 2) copper(I)iodide, tributylphosphine 3: 44 percent / tributyltin hydride, azobisisobutyronitrile / toluene / 0.25 h / 110 °C 4: 86 percent / hydrogen fluoride-pyridine / acetonitrile / 2.5 h / Ambient temperature 5: 86 percent / porcine liver esterase, phosphate buffer solution (pH=8) / acetone / 4 h / Ambient temperature View Scheme

1: 79 percent / mesyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 2: 1) t-butyllithium; 2) copper(I)iodide, tributylphosphine 3: 59 percent / NaBH4 / methanol / 0.67 h / 0 °C 4: 17 percent / 2) NH4OAc, 25percent aq. TiCl3 / 1) MeOH; 2) H2O, MeOH 5: 96 percent / hydrogen fluoride, pyridine / acetonitrile / 1 h / Ambient temperature 6: 84 percent / 5N NaOH / methanol / 6 h / 20 - 40 °C View Scheme

1: 79 percent / mesyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 2: 1) t-butyllithium; 2) copper(I)iodide, tributylphosphine 3: 42 percent / tributyltin hydride, azobisisobutyronitrile / toluene / 0.17 h / 110 °C 4: 88 percent / hydrogen fluoride-pyridine / acetonitrile / 2 h / Ambient temperature View Scheme

1: 79 percent / mesyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 2: 1) t-BuLi; 2) CuI, Bu3P; 5) 25percent aq. TiCl3, NH4OAc 3: 87 percent / hydrogen fluoride-pyridine / acetonitrile / 2.5 h / Ambient temperature View Scheme

1: 79 percent / mesyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C 2: 1) t-butyllithium; 2) copper(I)iodide, tributylphosphine 3: 1) triphenylphosphine; 2) 25percent aq. TiCl3, NH4OAc / 1) THF, rt., 15 min; 2) THF-water-MeOH, rt., 5 h 4: 92 percent / hydrogen fluoride-pyridine / acetonitrile / 1.5 h / Ambient temperature 5: 89 percent / porcine liver esterase, phosphate buffer solution (pH=8) / acetone; H2O / 20 h / Ambient temperature View Scheme

methanesulfonyl chloride; triethylamine in dichloromethane T=0°C; 1 h;

Multi-step reaction with 3 steps 1: 79 percent / mesyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C2: 1) t-butyllithium; 2) copper(I)iodide, tributylphosphine3: 42 percent / tributyltin hydride, azobisisobutyronitrile / toluene / 0.17 h / 110 °C  

Multi-step reaction with 4 steps 1: 79 percent / mesyl chloride, triethylamine / CH2Cl2 / 1 h / 0 °C2: 1) t-butyllithium; 2) copper(I)iodide, tributylphosphine3: 59 percent / NaBH4 / methanol / 0.67 h / 0 °C4: 2) NH4OAc, 25percent aq. TiCl3 / 1) MeOH; 2) H2O, MeOH