1.1: 67 percent / PCC; silica gel / CH2Cl2 / 4 h / 25 °C 2.1: 70 percent / n-Bu4NF / tetrahydrofuran / 0.25 h / 0 °C 3.1: 93 percent / NaBH4; CeCl3*7H2O / ethanol / 1 h / 0 °C 4.1: n-Bu3SnH; AIBN / toluene / 2.5 h / 80 °C 4.2: 71 percent / I2 / CH2Cl2 / 0.17 h / 25 °C 5.1: AsPh3 / Pd2(dba)3 / 1-methyl-pyrrolidin-2-one / 0.17 h 5.2: 67 percent / 1-methyl-pyrrolidin-2-one / 3 h / 30 °C 6.1: Dess-Martin periodinane; pyridne / CH2Cl2 / 1.5 h / 25 °C View Scheme

silica gel; pyridinium chlorochromate in dichloromethane T=25°C; 4 h;