lithium hexamethyldisilazane in tetrahydrofuran T=-78 - -5°C; Dieckman condensation;

<b>Multi-step reaction with 3 steps<br /> </b>1: 75 percent / 2,4-dinitrobenzenesulfenyl chloride; Et₃N / 1,2-dichloro-ethane / 90 &deg;C<br />2: Cs₂CO₃ <br />3: Et₃N / CH₂Cl₂ / 0 &deg;C<br /> <br /> &nbsp;

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '605283', constants.ctx, '0')">triethylamine</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '1730800', constants.ctx, '0')">dichloromethane</a> <br />T=0&deg;C;&nbsp;<br /> &nbsp;