1: 85 percent / Br2 / 1,2-dichloro-ethane / 0.75 h / 0 °C 2: 95 percent / CH3COOH, concd. HCl, water / 85 °C View Scheme

<b>Multi-step reaction with 2 steps<br /> </b>1: 53 percent / oxalyl chloride / toluene / 4 h / 90 &deg;C<br />2: 85 percent / triethylamine / CH₂Cl₂ / 0.25 h / -10 &deg;C<br /> <br /> &nbsp;