1: 93 percent / K2CO3 / methanol / 1 h / 0 °C 2: 1) methyl triflate, 2) N-methylimidazole / 1) THF, 0 deg C, 40 min, 2) THF 3: 89 percent / H2, NaOAc / 10percent Pd/C / methanol 4: 95 percent / CF3COOH / H2O; dioxane View Scheme

<b>Multi-step reaction with 12 steps<br /> </b>1: H₂ / 10percent Pd/C / ethyl acetate / 24 h / 760 Torr<br />2: Pb(NO₃)2, Et₃N / CH₂Cl₂ / 48 h / Ambient temperature<br />3: 94 percent / DIBAL / toluene / 0.5 h / -78 &deg;C<br />4: 1) N-chlorosuccinimide, Me₂S, 2) NEt₃ / 1) toluene, -25 deg C, 5.5 h, 2) 20 min.<br />5: 91 percent / tetrahydrofuran / 1 h / -40 deg C to r.t.<br />6: 1) N-chlorosuccinimide, Me₂S, 2) NEt₃ / 1) toluene, -25 deg C, 5.5 h 2) 20 min<br />7: HBr, H₂O / diethyl ether / 0.5 h / 0 &deg;C<br />8: NaHCO₃, Na₂CO₃ / H₂O / 2.5 h / Ambient temperature<br />9: 80 percent / pyridine / 20 h / 0 &deg;C<br />10: pyridine / CH₂Cl₂ / 0.33 h / -15 &deg;C<br />11: 1) Bu₄NOAc, 2) DMAP, Py / 1) CH₃CN, 40 deg C, 50 min, 2) 3 h, r.t.<br />12: 93 percent / NaBH₄ / ethanol<br /> <br /> &nbsp;

<b>Multi-step reaction with 11 steps<br /> </b>1: Pb(NO₃)2, Et₃N / CH₂Cl₂ / 48 h / Ambient temperature<br />2: 94 percent / DIBAL / toluene / 0.5 h / -78 &deg;C<br />3: 1) N-chlorosuccinimide, Me₂S, 2) NEt₃ / 1) toluene, -25 deg C, 5.5 h, 2) 20 min.<br />4: 91 percent / tetrahydrofuran / 1 h / -40 deg C to r.t.<br />5: 1) N-chlorosuccinimide, Me₂S, 2) NEt₃ / 1) toluene, -25 deg C, 5.5 h 2) 20 min<br />6: HBr, H₂O / diethyl ether / 0.5 h / 0 &deg;C<br />7: NaHCO₃, Na₂CO₃ / H₂O / 2.5 h / Ambient temperature<br />8: 80 percent / pyridine / 20 h / 0 &deg;C<br />9: pyridine / CH₂Cl₂ / 0.33 h / -15 &deg;C<br />10: 1) Bu₄NOAc, 2) DMAP, Py / 1) CH₃CN, 40 deg C, 50 min, 2) 3 h, r.t.<br />11: 93 percent / NaBH₄ / ethanol<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1: 80 percent / pyridine / 20 h / 0 &deg;C<br />2: pyridine / CH₂Cl₂ / 0.33 h / -15 &deg;C<br />3: 1) Bu₄NOAc, 2) DMAP, Py / 1) CH₃CN, 40 deg C, 50 min, 2) 3 h, r.t.<br />4: 93 percent / NaBH₄ / ethanol<br /> <br /> &nbsp;

<b>Multi-step reaction with 7 steps<br /> </b>1: 1) N-chlorosuccinimide, Me₂S, 2) NEt₃ / 1) toluene, -25 deg C, 5.5 h 2) 20 min<br />2: HBr, H₂O / diethyl ether / 0.5 h / 0 &deg;C<br />3: NaHCO₃, Na₂CO₃ / H₂O / 2.5 h / Ambient temperature<br />4: 80 percent / pyridine / 20 h / 0 &deg;C<br />5: pyridine / CH₂Cl₂ / 0.33 h / -15 &deg;C<br />6: 1) Bu₄NOAc, 2) DMAP, Py / 1) CH₃CN, 40 deg C, 50 min, 2) 3 h, r.t.<br />7: 93 percent / NaBH₄ / ethanol<br /> <br /> &nbsp;

<b>Multi-step reaction with 6 steps<br /> </b>1: HBr, H₂O / diethyl ether / 0.5 h / 0 &deg;C<br />2: NaHCO₃, Na₂CO₃ / H₂O / 2.5 h / Ambient temperature<br />3: 80 percent / pyridine / 20 h / 0 &deg;C<br />4: pyridine / CH₂Cl₂ / 0.33 h / -15 &deg;C<br />5: 1) Bu₄NOAc, 2) DMAP, Py / 1) CH₃CN, 40 deg C, 50 min, 2) 3 h, r.t.<br />6: 93 percent / NaBH₄ / ethanol<br /> <br /> &nbsp;