carbon tetrabromide in methanol T=65°C; 72 h;

1.1: 88 percent / NaBH4 / methanol / 2 h / 0 °C 2.1: 89 percent / PBr3 / CH2Cl2 / 12 h / 0 °C 3.1: 89 percent / toluene / 2 h / 100 °C 4.1: n-BuLi / tetrahydrofuran / -78 °C 4.2: tetrahydrofuran 5.1: 0.24 g / Bu4NF / tetrahydrofuran / 1 h View Scheme

1.1: 88 percent / NaBH4 / methanol / 2 h / 0 °C 2.1: 89 percent / PBr3 / CH2Cl2 / 12 h / 0 °C 3.1: 89 percent / toluene / 2 h / 100 °C 4.1: n-BuLi / tetrahydrofuran / -78 °C 4.2: tetrahydrofuran 5.1: 0.24 g / Bu4NF / tetrahydrofuran / 1 h View Scheme

NaBH(HFIP)3 in tetrahydrofuran; hexafluoroisopropyl alcohol T=25°C; 24 h; chemoselective reaction;

1: tetrahydrofuran / 20 °C 2: PCC; NaOAc; MgSO4 / CH2Cl2 3: NH2OH*HCl; NaOAc / ethanol; H2O / Heating 4: KF; 18-crown-6 / CH2Cl2; H2O 5: 21 percent / CuCl2 / PdCl2 / 760 Torr View Scheme