potassium hexamethylsilazane in tetrahydrofuran T=0°C;

1: 71 percent / K3Fe(CN)6; OsO4; (DHQ)2-PHAL / K2CO3; MeSO2NH2 / 2-methyl-propan-2-ol; H2O / 0 °C 2: 87 percent / pyridine / CH2Cl2 / 1.5 h / 0 °C 3: 89 percent / triphenylphosphine; triethylamine; formic acid / Pd2(dba)3*CHCl3 / tetrahydrofuran / 3 h / Heating 4: 64 percent / potassium tert-butoxide / tetrahydrofuran / 0 - 20 °C View Scheme

1: 89 percent / triphenylphosphine; triethylamine; formic acid / Pd2(dba)3*CHCl3 / tetrahydrofuran / 3 h / Heating 2: 64 percent / potassium tert-butoxide / tetrahydrofuran / 0 - 20 °C View Scheme