triphenylstannane in benzene 144 h; Heating;

1: CH3COOH / ethanol / 2 h / 40 °C 2: 2.) DBU / 1.) CH2Cl2, -30 deg C, 15 min, 2.) 0 deg C to r.t., 1 h 3: CH2O / tetrahydrofuran; H2O / 1 h / Ambient temperature 4: NaBH4 / methanol / 0.5 h / 0 °C 5: 2 N HCl / 0.5 h / Ambient temperature View Scheme

1: 73 percent / O2, Rose Bengal / methanol / 48 h / Irradiation 2: 14 percent / CoTPP / diethyl ether; CHCl3 / 0.25 h / Heating 3: 98 percent / H2 / Pd-C / ethanol / 3 h View Scheme

1: 1.) Bu3SnH, Pd(PPh3)4, NH4Cl, 2.) NaF / 1.) THF, H2O, room temperature, 2 h, 2.) EtOAc 2: 95 percent / NaBH4 / 0 °C View Scheme