1: With hydrogenchloride; sodium nitrite 0.5 h; cooling; 2: With potassium iodide T=80°C; 2 h;

<b>Multi-step reaction with 4 steps<br /> </b>1: 1.) Hg(OAc)2, 2.) KI, I₂ / 1.) H₂O, 100 deg C, 0.5 h, 2.) H₂O, RT, 3 h<br />2: KOH<br />3: Cu / dimethylformamide / Heating<br />4: H₂ / Pd/C<br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1.1: pyridine; 4-(N,N-dimethlyamino)pyridine / dichloromethane / 2 h / 0 &deg;C<br />2.1: n-butyllithium / tetrahydrofuran; hexane / 0 &deg;C<br />2.2: -78 - 20 &deg;C<br />2.3: -78 - 20 &deg;C<br />3.1: hydrogenchloride; water / 1,4-dioxane / 6 h / Reflux<br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1.1: pyridine; 4-(N,N-dimethlyamino)pyridine / dichloromethane / 2 h / 0 &deg;C<br />2.1: n-butyllithium / tetrahydrofuran; hexane / 0 &deg;C<br />2.2: -78 - 20 &deg;C<br />2.3: -78 - 20 &deg;C<br />3.1: hydrogenchloride; water / 1,4-dioxane / 6 h / Reflux<br /> <br /> &nbsp;