1.1: triethylamine / N,N-dimethyl aminopyride / methanol / 24 h 2.1: sodium methylate / methanol / 0.5 h / 20 °C 2.2: 4 h / 80 °C 2.3: 1 h / 50 °C View Scheme

<b>Multi-step reaction with 4 steps<br /> </b>1.1: oxalyl dichloride / N,N-dimethyl-formamide / acetonitrile / 4.5 h / 0 - 40 &deg;C / Inert atmosphere<br />2.1: AlCl₃, aluminium chloride / dichloromethane / 1.75 h / 30 - 40 &deg;C / Inert atmosphere<br />2.2: Cooling with ice<br />3.1: AlCl₃, aluminium chloride; 1,1,3,3-tetramethyldisiloxane / dichloromethane / 0 - 5 &deg;C / Inert atmosphere<br />4.1: hydrogen / platinum on activated charcoal / tetrahydrofuran / 20 &deg;C / 760.05 Torr<br /> <br /> &nbsp;