boron trichloride in dichloromethane T=-78°C; 4 h;

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '103233', constants.ctx, '0')">pyridine</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '607898', constants.ctx, '0')">p-toluenesulfonyl chloride</a> <br />&nbsp;Ambient temperature;&nbsp;<br /> &nbsp;

<b>Multi-step reaction with 2 steps<br /> </b>2: 76 percent / tosyl chloride, pyridine / Ambient temperature<br /> <br /> &nbsp;