1: potassium carbonate / N,N-dimethyl-formamide; water / 35 °C / |Large scale 2: palladium on carbon; acetic acid / tetrahydrofuran / 60 °C / 1725.17 Torr / |Large scale View Scheme

<b>Multi-step reaction with 3 steps<br /> </b>1: tetrahydrofuran / 0.67 h / 20 - 25 &deg;C / |Large scale<br />2: methanesulfonic acid; hydrogen bromide / n-heptane / 0.5 h / 65 - 75 &deg;C / |Large scale<br />3: potassium carbonate / N,N-dimethyl-formamide / 0.5 h / |Large scale<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1.1: 1,1'-carbonyldiimidazole / tetrahydrofuran / 1.5 h / 5 - 7 &deg;C / |Large scale<br />1.2: 23 - 25 &deg;C / |Large scale<br />1.3: 25 &deg;C / |Large scale<br />2.1: tetrahydrofuran / 0.67 h / 20 - 25 &deg;C / |Large scale<br />3.1: methanesulfonic acid; hydrogen bromide / n-heptane / 0.5 h / 65 - 75 &deg;C / |Large scale<br />4.1: potassium carbonate / N,N-dimethyl-formamide / 0.5 h / |Large scale<br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1: tetrahydrofuran / 0.67 h / 20 - 25 &deg;C / |Large scale<br />2: methanesulfonic acid; hydrogen bromide / n-heptane / 0.5 h / 65 - 75 &deg;C / |Large scale<br />3: potassium carbonate / N,N-dimethyl-formamide / 0.5 h / |Large scale<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1: magnesium; diisobutylaluminium hydride / tetrahydrofuran; n-heptane / 50 - 55 &deg;C<br />2: tetrahydrofuran / 0.67 h / 20 - 25 &deg;C / |Large scale<br />3: methanesulfonic acid; hydrogen bromide / n-heptane / 0.5 h / 65 - 75 &deg;C / |Large scale<br />4: potassium carbonate / N,N-dimethyl-formamide / 0.5 h / |Large scale<br /> <br /> &nbsp;