potassium hydroxide in dimethyl sulfoxide 3.5 h; heating;

<b>Multi-step reaction with 2 steps<br /> </b>1: 1.) triethyloxonium fluoroborate / 1.) ClCH₂CH₂Cl, reflux 16 h<br />2: 1.) t-butyllithium / 1.) -78 deg C, THF, 45 min at -25 deg C, 2.) -78 deg C, THF, 1 h up to -30 deg C<br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1: Heating<br />2: 1.) triethyloxonium fluoroborate / 1.) ClCH₂CH₂Cl, reflux 16 h<br />3: 1.) t-butyllithium / 1.) -78 deg C, THF, 45 min at -25 deg C, 2.) -78 deg C, THF, 1 h up to -30 deg C<br /> <br /> &nbsp;

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '3587204', constants.ctx, '0')">tert.-butyl lithium</a> <br />&nbsp;1.) -78 deg C, THF, 45 min at -25 deg C, 2.) -78 deg C, THF, 1 h up to -30 deg C;&nbsp;&nbsp;Yield given. Multistep reaction;&nbsp;<br /> &nbsp;