lithium hexamethyldisilazane in tetrahydrofuran T=-78 - 20°C;

<b>Multi-step reaction with 2 steps<br /> </b>1: 1.) AlCl₃ / 1.) CH₂Cl₂, 25 deg C, 1 h, 2.) CH₂Cl₂, 25 deg C, 18 h<br />2: 94 percent / p-toluenesulfonic acid / benzene / 192 h / Heating<br /> <br /> &nbsp;