1: 89 percent / NaBH4 / methanol / 2.5 h 2: 83 percent / p-TsOH / benzene / 1 h / Heating 3: 87 percent / DDQ / benzene / 4 h / Heating View Scheme

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '1446024', constants.ctx, '0')">methanesulfonic acid</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '1730800', constants.ctx, '0')">dichloromethane</a> <br />&nbsp;Ambient temperature;&nbsp;<br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1: 100 percent / Et₃N / CH₂Cl₂ / 2 h / Ambient temperature<br />2: 97 percent / NaI / acetone / 16 h / Heating<br />3: 50 percent / t-BuLi, HMPA / tetrahydrofuran / -78 &deg;C<br />4: 98 percent / CH₃SO₃H / CH₂Cl₂ / Ambient temperature<br /> <br /> &nbsp;

<b>Multi-step reaction with 2 steps<br /> </b>1: 50 percent / t-BuLi, HMPA / tetrahydrofuran / -78 &deg;C<br />2: 98 percent / CH₃SO₃H / CH₂Cl₂ / Ambient temperature<br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1: 97 percent / NaI / acetone / 16 h / Heating<br />2: 50 percent / t-BuLi, HMPA / tetrahydrofuran / -78 &deg;C<br />3: 98 percent / CH₃SO₃H / CH₂Cl₂ / Ambient temperature<br /> <br /> &nbsp;

<b>Multi-step reaction with 5 steps<br /> </b>1: 70 percent / n-BuLi / diethyl ether; hexane / 1.) -78 deg C, 30 min, 2.) 1.5 h<br />2: 100 percent / Et₃N / CH₂Cl₂ / 2 h / Ambient temperature<br />3: 97 percent / NaI / acetone / 16 h / Heating<br />4: 50 percent / t-BuLi, HMPA / tetrahydrofuran / -78 &deg;C<br />5: 98 percent / CH₃SO₃H / CH₂Cl₂ / Ambient temperature<br /> <br /> &nbsp;