1: tetrahydrofuran / 3 h 2: hydrogenchloride / 16 h / 85 °C / |Inert atmosphere View Scheme

<b>Multi-step reaction with 2 steps<br /> </b>1: 54.4 percent / Et₃N / ethyl acetate / 1 h<br />2: 81 percent / BuLi / tetrahydrofuran; hexane / -10 deg C -&gt; r.t.<br /> <br /> &nbsp;