1: NCS, AgNO3 / H2O; acetonitrile 2: I2, KOH / 43 °C 3: KOH / methanol; H2O View Scheme

&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '102391', constants.ctx, '0')">tetrahydrofuran</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '1696894', constants.ctx, '0')">diethyl ether</a> <br />T=-78&deg;C;&nbsp;3&nbsp;h;&nbsp;<br /> &nbsp;