1: 83 percent / pyridine / ethanol / Heating 2: FeSO4, aq. conc. NH3 / 0.25 h / Heating 3: TsOH / toluene; tetrahydrofuran / 48 h / Heating View Scheme

2: triethylamine / CH2Cl2 / Ambient temperature 3: 0.8 g / HCl / ethanol / 48 h / Ambient temperature View Scheme

<b>Multi-step reaction with 3 steps<br /> </b>1: 96 percent / aq. KOH / ethanol<br />2: oxalyl chloride / benzene; dimethylformamide / 1 h / Ambient temperature<br />3: aq. Na₂CO₃ / tetrahydrofuran / 1 h / Ambient temperature<br /> <br /> &nbsp;

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '4154566', constants.ctx, '0')">sodium carbonate</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '102391', constants.ctx, '0')">tetrahydrofuran</a> <br />1&nbsp;h;&nbsp;&nbsp;Ambient temperature;&nbsp;&nbsp;Yield given;&nbsp;<br /> &nbsp;