1.1: naphthalene; lithium; zinc(II) chloride / tetrahydrofuran; methanol / 50 °C 2.1: oxalyl dichloride; dimethyl sulfoxide / dichloromethane / -78 - -10 °C 2.2: -78 - 20 °C 3.1: potassium tert-butylate / tetrahydrofuran / 0.5 h / 20 °C 3.2: 2 h / 0 °C View Scheme

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '4123663', constants.ctx, '0')">diisobutylaluminium hydride</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '1696894', constants.ctx, '0')">diethyl ether</a> <br />T=0&deg;C;&nbsp;<br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1.1: 80 percent / dimethylsulfoxide; oxalyl chloride; triethylamine / CH₂Cl₂ / 1.33 h / -78 - 20 &deg;C<br />2.1: n-BuLi / tetrahydrofuran; hexane / 0.33 h / 0 &deg;C<br />2.2: 78 percent / tetrahydrofuran; hexane / 1 h / 0 - 20 &deg;C<br />3.1: 81 percent / DIBAL / tetrahydrofuran / 2 h / -78 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1.1: toluene-4-sulfonic acid / methanol / 2 h / 20 &deg;C<br />2.1: oxalyl dichloride; dimethyl sulfoxide / dichloromethane / -78 - -10 &deg;C<br />2.2: -78 - 20 &deg;C<br />3.1: sodium hydride / diethyl ether; mineral oil / 0 &deg;C<br />3.2: 0 &deg;C<br />4.1: diisobutylaluminium hydride / diethyl ether / 0 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 6 steps<br /> </b>1.1: ethylmagnesium bromide / tetrahydrofuran / 50 &deg;C<br />1.2: 20 - 50 &deg;C<br />2.1: potassium <i>tert</i>-butylate; dimethyl sulfoxide / tetrahydrofuran / -40 &deg;C<br />3.1: toluene-4-sulfonic acid / methanol / 2 h / 20 &deg;C<br />4.1: oxalyl dichloride; dimethyl sulfoxide / dichloromethane / -78 - -10 &deg;C<br />4.2: -78 - 20 &deg;C<br />5.1: sodium hydride / diethyl ether; mineral oil / 0 &deg;C<br />5.2: 0 &deg;C<br />6.1: diisobutylaluminium hydride / diethyl ether / 0 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 7 steps<br /> </b>1.1: toluene-4-sulfonic acid / dichloromethane / 0.5 h / 0 - 5 &deg;C<br />2.1: ethylmagnesium bromide / tetrahydrofuran / 50 &deg;C<br />2.2: 20 - 50 &deg;C<br />3.1: potassium <i>tert</i>-butylate; dimethyl sulfoxide / tetrahydrofuran / -40 &deg;C<br />4.1: toluene-4-sulfonic acid / methanol / 2 h / 20 &deg;C<br />5.1: oxalyl dichloride; dimethyl sulfoxide / dichloromethane / -78 - -10 &deg;C<br />5.2: -78 - 20 &deg;C<br />6.1: sodium hydride / diethyl ether; mineral oil / 0 &deg;C<br />6.2: 0 &deg;C<br />7.1: diisobutylaluminium hydride / diethyl ether / 0 &deg;C<br /> <br /> &nbsp;