1: Jones reagent / 0.33 h 2: KOH / 50 °C View Scheme

<b>Multi-step reaction with 4 steps<br /> </b>1: 1.) n-BuLi, 1/2CuBr-Me₂S<br />2: DBU / CH₂Cl₂ / 1 h / -78 &deg;C<br />3: 60 percent / xylene / 4 h / 140 &deg;C<br />4: 81 percent / O₃, Me₂S / 12 h<br /> <br /> &nbsp;