1: 85 percent / oxalyl chloride; DMSO; Et3N / CH2Cl2 / 2 h / -78 - 20 °C 2: 93 percent / diethyl ether / 0.5 h / 20 °C 3: 86 percent / Et3N / CH2Cl2 / 1 h / 20 °C 4: 83 percent / [(CF3)2C(Me)O]2Mo[CHCMe2Ph][N-2,6-diisopropylphenyl)] / benzene / 24 h / 20 °C 5: π-allylpalladium chloride dimer; tetrabutylammonium fluoride / tetrahydrofuran / 60 h / 20 °C View Scheme