1: 72 percent / H2SO4 / acetic acid / 1 h / 75 - 80 °C 2: 96 percent / Et3SiH; TiCl4 / CH2Cl2 / 24 h / 20 °C 3: 62 percent / Na; NH3 / tetrahydrofuran / 0 h / -78 °C 4: BBr3 / CH2Cl2 / 2 h / -15 °C 5: 68 percent / H2SO4 / H2O / 12 h / 20 °C View Scheme

1: 99 percent / H2 / Pd/C / ethyl acetate / 2.5 h / 2585.7 Torr 2: 51 percent / Na, liquid NH3 / tetrahydrofuran / 0.01 h 3: 1M H2SO4 / 36 h / Heating View Scheme

<b>With</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '742035', constants.ctx, '0')">trifluoroacetic acid</a>&nbsp;<b>in</b>&nbsp; <a href="#" onclick="return RXDsubstances(event, this, '1730800', constants.ctx, '0')">dichloromethane</a> <br />78&nbsp;h;&nbsp;&nbsp;Heating;&nbsp;<br /> &nbsp;

<b>Multi-step reaction with 2 steps<br /> </b>1: 72 percent / Et₃N; DMAP / CH₂Cl₂ <br />2: 6 percent / TFA / CH₂Cl₂ <br /> <br /> &nbsp;

<b>Multi-step reaction with 3 steps<br /> </b>1: Cl₂CHOCH₃ / CH₂Cl₂ / 1.) room temperature, 20 min, 2.) 50-55 deg C, 30 min<br />2: Et₃N, DMAP / CH₂Cl₂ / 6 h / Ambient temperature<br />3: 98 percent / TFA / CH₂Cl₂ / 78 h / Heating<br /> <br /> &nbsp;

<b>Multi-step reaction with 2 steps<br /> </b>1: Et₃N, DMAP / CH₂Cl₂ <br />2: CF₃COOH / CH₂Cl₂ <br /> <br /> &nbsp;