1: 100 percent / TFA 2: 1.) diphenyl phosphorazidate, Et3N, 2.) aq. HCl / 1.) toluene, reflux, 2.) reflux, 2 h 3: 49 percent / NaOMe / methanol / Ambient temperature 4: 95 percent / tetrahydrofuran / Ambient temperature View Scheme

<b>Multi-step reaction with 4 steps<br /> </b>1: 95 percent / MsN₃, Et₃N<br />2: 62 percent / 5 mol percent of rhodium pivalate &lt;Rh₂(piv)4&gt; / benzene / 1 h / Heating<br />3: 1.) O₃, 2.) DMS / 1.) CH₂Cl₂, MeOH<br />4: tetrahydrofuran / Ambient temperature<br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1: 62 percent / 5 mol percent of rhodium pivalate &lt;Rh₂(piv)4&gt; / benzene / 1 h / Heating<br />2: 1.) O₃, 2.) DMS / 1.) CH₂Cl₂, MeOH<br />3: tetrahydrofuran / Ambient temperature<br /> <br /> &nbsp;