Hantzsch ester; titanium tetrachloride in tetrahydrofuran; dichloromethane T=20°C; 1 h; regioselective reaction;

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '102438', constants.ctx, '0')">piperidine</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '506007', constants.ctx, '0')">acetic acid</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '635760', constants.ctx, '0')">toluene</a> <br />12&nbsp;h;&nbsp;&nbsp;Reflux;&nbsp;<br /> &nbsp;