1: 1.) Br2; 2.) tBuOK / 1.) pentane, -15 deg C; 2.) 0 deg C, 120 min 2: 92 percent / NaNH2 in liq NH3 / pentane; diethyl ether / 0.3 h 3: 59 percent / HgSO4, 6NH2SO4 / diethyl ether; pentane / 2.75 h / Ambient temperature View Scheme

potassium tert-butylate; bromine 1.) pentane, -15 deg C; 2.) 0 deg C, 120 min; Yield given. Multistep reaction;

1: 1.) Br2; 2.) tBuOK / 1.) pentane, -15 deg C; 2.) 0 deg C, 120 min 2: 92 percent / NaNH2 in liq NH3 / pentane; diethyl ether / 0.3 h View Scheme

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '4948473', constants.ctx, '0')">magnesium</a>;&nbsp;<a href="#" onclick="return RXDsubstances(event, this, '605266', constants.ctx, '0')">ethylene dibromide</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '102391', constants.ctx, '0')">tetrahydrofuran</a> <br />&nbsp;Irradiation1.) 50 deg C, 45 min then, 2.) 40 deg C, 30 min then room temp.;&nbsp;<br /> &nbsp;

<b>Multi-step reaction with 2 steps<br /> </b>1: 97 percent / PCl₅ / CCl₄ / 1.5 h / -12 &deg;C<br />2: Mg, 1,2-dibromoethane / tetrahydrofuran / Irradiation; 1.) 50 deg C, 45 min then, 2.) 40 deg C, 30 min then room temp.<br /> <br /> &nbsp;

<b>Multi-step reaction with 2 steps<br /> </b>1: PhCOCl / benzene / Heating<br />2: PhLi / diethyl ether<br /> <br /> &nbsp;