1: n-butyllithium / Inert atmosphere 2: hydrogenchloride / ethanol; water / Inert atmosphere 3: triethylamine; magnesium chloride / acetonitrile / 0.5 h / Inert atmosphere; Reflux 4: potassium carbonate / N,N-dimethyl-formamide / 2 h / 0 °C / Inert atmosphere View Scheme

1.1: n-butyllithium; N,N,N',N,-tetramethylethylenediamine / diethyl ether; hexane / 5 h / 0 °C / Inert atmosphere 1.2: 0 °C / Inert atmosphere 2.1: trimethylsilyl bromide / dichloromethane / 0.5 h / 0 °C / Inert atmosphere 2.2: Inert atmosphere View Scheme

1: With N,N,N',N,-tetramethylethylenediamine in diethyl ether; pentane T=-78°C; 1 h; 2: With bromine in diethyl ether; pentane T=-78 - 0°C; 3 h; 3: With hydrogenchloride in methanol; water T=40°C; 5 h; Further stages.;

1: 1.) n-BuLi / 1.) Et2O, TMEDA, hexane, 0 deg C, 1 h, 2.) from 0 deg C to RT 2: (COCl)2, DMF / CH2Cl2 / 1 h / 0 °C 3: CH2Cl2 / 1.5 h / 0 °C View Scheme

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '110354', constants.ctx, '0')">4-(N,N-dimethlyamino)pyridine</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '605301', constants.ctx, '0')">N-ethyl-N,N-diisopropylamine</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '1730800', constants.ctx, '0')">dichloromethane</a> <br />T=0 - 20&deg;C;&nbsp;&nbsp;Inert atmosphere;&nbsp;<br /> &nbsp;