oxalyl dichloride; dimethyl sulfoxide; triethylamine in dichloromethane T=-78 - 20°C; Swern oxidation;

1: 99 percent / toluene / Heating 2: DIBAL-H / diethyl ether; hexane / 1 h / 0 °C 3: 9.9 g / (COCl)2; DMSO; Et3N / CH2Cl2 / -78 - 20 °C View Scheme

1: 94 percent / (COCl)2; DMSO; Et3N / CH2Cl2 / -78 - 20 °C 2: 99 percent / toluene / Heating 3: DIBAL-H / diethyl ether; hexane / 1 h / 0 °C 4: 9.9 g / (COCl)2; DMSO; Et3N / CH2Cl2 / -78 - 20 °C View Scheme

1: DIBAL-H / diethyl ether; hexane / 1 h / 0 °C 2: 9.9 g / (COCl)2; DMSO; Et3N / CH2Cl2 / -78 - 20 °C View Scheme

1: 95 percent / DIBAL-H / diethyl ether; hexane / 1 h / 0 °C 2: 94 percent / (COCl)2; DMSO; Et3N / CH2Cl2 / -78 - 20 °C 3: 99 percent / toluene / Heating 4: DIBAL-H / diethyl ether; hexane / 1 h / 0 °C 5: 9.9 g / (COCl)2; DMSO; Et3N / CH2Cl2 / -78 - 20 °C View Scheme

1: 98 percent / toluene / Heating 2: 95 percent / DIBAL-H / diethyl ether; hexane / 1 h / 0 °C 3: 94 percent / (COCl)2; DMSO; Et3N / CH2Cl2 / -78 - 20 °C 4: 99 percent / toluene / Heating 5: DIBAL-H / diethyl ether; hexane / 1 h / 0 °C 6: 9.9 g / (COCl)2; DMSO; Et3N / CH2Cl2 / -78 - 20 °C View Scheme

1: 92 percent / toluene / Heating 2: 97 percent / DIBAL-H / diethyl ether; hexane / 1 h / 20 °C View Scheme

1: 92 percent / toluene / Heating 2: 97 percent / DIBAL-H / diethyl ether; hexane / 1 h / 20 °C 3: 57 percent / (COCl)2; DMSO; Et3N / CH2Cl2 / -78 - 20 °C View Scheme

1.1: Zn; pyridine; PPh3 / CH2Cl2 / 0.5 h / 22 °C 1.2: 98 percent / CH2Cl2 / 2 h / 22 °C 2.1: 35 percent / TlOEt / Pd(PPh3)4 / tetrahydrofuran; H2O / 0.5 h / 22 °C 3.1: 89 percent / Pd(t-Bu3P)2 / tetrahydrofuran; toluene / 0.75 h / 22 °C View Scheme