1: 1.) methanesulfonyl chloride, triethylamine, 2.) DBU / 1.) CH2Cl2, room temperature, 30 min, 2.) CH2Cl2, room temperature 2: PdCl2(PhCN)2, CuI, piperidine / 1 h / Ambient temperature 3: 79 percent / Red-Al / tetrahydrofuran; toluene / Ambient temperature 4: 80 percent / MnO2 / CH2Cl2 / 1 h View Scheme

1: 1.) methanesulfonyl chloride, triethylamine, 2.) DBU / 1.) CH2Cl2, room temperature, 30 min, 2.) CH2Cl2, room temperature 2: 78 percent / PdCl2(PPh3)2, triethylamine / tetrahydrofuran / 4 h View Scheme