1: Tl2CO3, Pd<P(C6H5)3>4 / benzene / 23 h / Ambient temperature 2: nBuNF, HMPA, 4 Angstroem molecular sieves / tetrahydrofuran / 8 h / Ambient temperature 3: MnO2 / CH2Cl2 / 1 h / Heating View Scheme