lithium hydroxide Yield given;

<b>Multi-step reaction with 4 steps<br /> </b>1: 1.)LDA, ZnBr₂ / 1.)THF, -78 deg C, 60 min; 2.)THF, -15 deg C, 24 h<br />2: 92 percent / LiBr, DBU / tetrahydrofuran / 4 h / Ambient temperature<br />3: 92 percent / BuLi / tetrahydrofuran / 0 - 20 &deg;C<br />4: 1.)LDA, ZnBr₂ / 1.)THF, -78 deg C, 60 min; 2.)THF, -15 deg C, 24 h<br /> <br /> &nbsp;

<b>Multi-step reaction with 5 steps<br /> </b>1: diethyl ether / 9 h / Heating<br />2: Et₃N / CH₂Cl₂ / -25 - 0 &deg;C<br />3: NaOH / methanol / 9 h / Heating<br />4: 92 percent / BuLi / tetrahydrofuran / 0 - 20 &deg;C<br />5: 1.)LDA, ZnBr₂ / 1.)THF, -78 deg C, 60 min; 2.)THF, -15 deg C, 24 h<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1.1: Mg / tetrahydrofuran<br />1.2: 54 percent / tetrahydrofuran / 4 h / 20 &deg;C<br />2.1: 73 percent / aq. KOH / toluene / 2 h / 20 &deg;C<br />3.1: n-BuLi / tetrahydrofuran; hexane / 2 h / -78 &deg;C<br />3.2: 70 percent / tetrahydrofuran; hexane / 24.5 h / -78 - 20 &deg;C<br />4.1: LDA / tetrahydrofuran; hexane / 1 h / 0 &deg;C<br />4.2: tetrahydrofuran; hexane / 24 h / 0 &deg;C<br /> <br /> &nbsp;

<b>Multi-step reaction with 4 steps<br /> </b>1: 54 percent<br />2: 73 percent / KOH / toluene<br />3: 70 percent / BuLi / -78 &deg;C<br />4: LDA / 0 &deg;C<br /> <br /> &nbsp;