1.1: 1.39 g / m-chloroperoxybenzoic acid / CH2Cl2; CHCl3 2.1: potassium hydride / tetrahydrofuran / 1.25 h / 0 - 20 °C 2.2: 63 percent / Selectfluor / tetrahydrofuran; dimethylformamide / 2.08 h 3.1: 91 percent / tributyltin chloride; 2,2'-azobisisobutyronitrile; polymethylhydrosiloxane / potassium fluoride / toluene; H2O / 3 h / Heating View Scheme