1.1: phosphorus tribromide / diethyl ether / 20 °C / Inert atmosphere 2.1: copper(l) iodide; potassium carbonate; sodium iodide / N,N-dimethyl-formamide / 40 h / 20 °C / Inert atmosphere 3.1: phosphorus tribromide / diethyl ether / 20 °C / Inert atmosphere 4.1: copper(l) iodide; potassium carbonate; sodium iodide / N,N-dimethyl-formamide / 24 h / 20 °C / Inert atmosphere 5.1: quinoline; hydrogen / ethyl acetate / 1 h / 20 °C / Inert atmosphere 6.1: lithium hydroxide hydrate / tetrahydrofuran / 16 h / 20 °C / Inert atmosphere 6.2: pH 2 / Inert atmosphere View Scheme

<b>Multi-step reaction with 2 steps<br /> </b>1: 96 percent / TsOH / CH₂Cl₂ / 24 h / Heating<br />2: 85 percent / CuI; NaI; K₂CO₃ / dimethylformamide / 20 h / 30 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1: Jones reagent<br />2: sulfonic acid resin<br />3: 86 percent / K₂CO₃, NaI, CuI / dimethylformamide / 12 h<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1: NaNH₂ / various solvent(s)<br />2: Jones reagent<br />3: sulfonic acid resin<br />4: 86 percent / K₂CO₃, NaI, CuI / dimethylformamide / 12 h<br /> <br /> &nbsp;