tetrabutyl ammonium fluoride in N,N-dimethyl-formamide 1.5 h; Ambient temperature;

<b>Multi-step reaction with 3 steps<br /> </b>1: 77 percent / pyridine / 5 h / 100 &deg;C<br />2: 45 percent / Hg(OAc)2, BF₃*Et₂O<br />3: 75 percent / p-TsOH / CH₂Cl₂ / 12 h / 40 &deg;C<br /> <br /> &nbsp;