1: 90 percent / i-Pr2NEt / CH2Cl2 / Ambient temperature 2: 99 percent / cerium(IV) diammonium nitrate / acetonitrile; H2O / 0 °C 3: 96 percent / PDC / CH2Cl2 / Ambient temperature 4: toluene / -78 °C 5: 62 percent / PhSH, BF3*Et2O / CH2Cl2 / 0 °C 6: 96 percent / 2,6-lutidine / CH2Cl2 / 0 °C 7: Pd2(dba)3PPh3-Et3N / toluene / 6 h / 120 °C 8: camphorsulfonic acid / methanol View Scheme

<b>Multi-step reaction with 5 steps<br /> </b>1: triphenylphosphine; diethylazodicarboxylate / tetrahydrofuran; toluene / 0 - 80 &deg;C / |Inert atmosphere<br />2: AD-mix β / water; tert-butanol / 4 h / 0 &deg;C<br />3: pyridine / 20 h / 0 &deg;C / |Inert atmosphere<br />4: lithium hexamethyldisilazane / tetrahydrofuran / 0.5 h / 0 &deg;C / |Inert atmosphere<br />5: dimethyl sulfoxide / 0.5 h / 20 &deg;C / |Inert atmosphere<br /> <br /> &nbsp;