1: n-BuLi / hexane; tetrahydrofuran / 1 h / -70 °C 2: concentrated HCl / tetrahydrofuran / Ambient temperature View Scheme

<b>Multi-step reaction with 4 steps<br /> </b>1: 64 percent / hydroxylamine hidrochloride, KOH / tetrahydrofuran; ethanol / Ambient temperature<br />2: n-BuLi / hexane; tetrahydrofuran / 1 h / Ambient temperature<br />3: concentrated H₂SO₄ / tetrahydrofuran; hexane / 1 h / Heating<br />4: p-toluenesulfonic acid monohydrate / Ambient temperature<br /> <br /> &nbsp;

<b>Multi-step reaction with 5 steps<br /> </b>1: 80 percent / p-toluenesulfonic acid monohydrate / 6 h / Ambient temperature<br />2: 64 percent / hydroxylamine hidrochloride, KOH / tetrahydrofuran; ethanol / Ambient temperature<br />3: n-BuLi / hexane; tetrahydrofuran / 1 h / Ambient temperature<br />4: concentrated H₂SO₄ / tetrahydrofuran; hexane / 1 h / Heating<br />5: p-toluenesulfonic acid monohydrate / Ambient temperature<br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1: n-BuLi / hexane; tetrahydrofuran / 1 h / Ambient temperature<br />2: concentrated H₂SO₄ / tetrahydrofuran; hexane / 1 h / Heating<br />3: p-toluenesulfonic acid monohydrate / Ambient temperature<br /> <br /> &nbsp;

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '472690', constants.ctx, '0')">toluene-4-sulfonic acid</a> <br />&nbsp;Ambient temperature;&nbsp;<br /> &nbsp;