1.1: ammonium sulfate; hexamethyldisilazane / Heating 1.2: 32 percent / 4 Angstroem molecular sieves; NBS / toluene / 0 - 20 °C 2.1: 87 percent / tetraethylammonium fluoride hydrate / acetone / 20 °C View Scheme

<b>Multi-step reaction with 3 steps<br /> </b>1: 94 percent / Dowex 50wx-100 ion-exchange resin / 17 h / 20 &deg;C<br />2: 78 percent / DMAP; Et₃N / CH₂Cl₂; dimethylformamide / 0 - 20 &deg;C<br />3: zinc iodide; tetrabutylammnoum iodide / CH₂Cl₂ / 1 h / -15 &deg;C<br /> <br /> &nbsp;

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '3916152', constants.ctx, '0')">tetra-(n-butyl)ammonium iodide</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '8128156', constants.ctx, '0')">zinc(II) iodide</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '1730800', constants.ctx, '0')">dichloromethane</a> <br />T=-15&deg;C;&nbsp;1&nbsp;h;&nbsp;<br /> &nbsp;

<b>Multi-step reaction with 2 steps<br /> </b>1: 78 percent / DMAP; Et₃N / CH₂Cl₂; dimethylformamide / 0 - 20 &deg;C<br />2: zinc iodide; tetrabutylammnoum iodide / CH₂Cl₂ / 1 h / -15 &deg;C<br /> <br /> &nbsp;